Regulation of the activity of enzymes and methods. Regulation of enzyme activity. Medical enzymology (biochemistry) Ways of regulation of enzyme activity in clitin
Being a single living matter, which functions like a complex of critical biosystems, the clitina is constantly exchanged with the ethereal medium of speech and energy. To support homeostasis, there is a group of special speeches of protein nature - enzymes. Budov, functions, as well as regulation of the activity of enzymes, are developed in a special way of biochemistry, as they are called enzymology. In this article, on specific applications, it is possible to look at different mechanisms and ways of regulating the activity of enzymes, the power of the greater powers and people.
Wash necessary for optimal enzyme activity
Biologically active speech, which vibrates like a reaction to assimilation, as well as to splitting, reveals its catalytic power in clitins for singing minds. For example, it is important to say that a chemical process is going on in such a dilyantsi clitin, which will take the fate of enzymes. Zavdyaks of compartmentalization (split of cytoplasm on the plots) antagonistic reactions occur in various parts and organoids.
Thus, the synthesis of proteins occurs in ribosomes, while splitting - in hialoplasm. The specific regulation of the activity of enzymes that catalyze the proliferating biochemical reactions, ensuring the optimal flow of the exchange of speech, and the reshaping of energetically fertile metabolic pathways.
Multi-enzyme complex
Structural-functional organization of enzymes in the body of the enzymatic apparatus of clitin. More chemical reactions, like in them, mutually. As a rich product of the first reaction, as a reagent for the attack, in this case, the expansion of enzymes in clitin is especially pronounced.
Keep in mind that enzymes, by their nature, are simple and collapsible proteins. The first sensitivity to the clitin substrate is explained by the change in the airy space configuration of the tertiary quarter structure of the peptide. Enzymes react to changes not only in the middle of the clitin parameters, such as the chemical warehouse of hyaloplasma, the concentration of reagents and products in the reaction, temperature, but also to changes that occur in the susceptible clitins or intercellular rindine i.
Why is the clitina divided into compartments
The intelligence and logic of the arrangement of living nature is simply hostile. The whole world is worthy of the life manifestations that are characteristic of the clitin. For a scientific chemist, it was generally understood that different enzymatic chemical reactions, for example, the synthesis of glucose and glycolosis, cannot proceed in the same sample. How do protracted reactions occur in the hyaloplasm of one cell, which is the substrate for their conduction? It appears that the cytosol is the cytosol, in which antagonistic chemical processes take place, the space of divisions and the isolation of loci - compartments. Zavdyaks and metabolic reactions of the greater savts and those people are regulated especially precisely, and the products of the exchange are transformed into forms that can easily penetrate through the partitions of the cells. Let them restore their primary structure. Cream to the cytosol, enzymes are located in organelles: ribosomes, mitochondria, nuclei, lysosomes.
The role of enzymes in energy metabolism
Let's take a look at the oxide decarboxylation of pyruvate. The regulation of the catalytic activity of enzymes has been well developed by enzymology. This biochemical process takes place in mitochondria – two-membrane organelles of eukaryotic clitins – and is an intermediate process between acid-free degradation of glucose and Pyruvate dehydrogenase complex – PDH – to avenge three enzymes. In other people, this decrease is due to the increase in the concentration of Acetyl-CoA and NATH, so that alternative possibilities for the absorption of Acetyl-CoA molecules appear. If clitin requires an additional portion of energy and vimagan acceptor molecules to enhance the reactions of the tricarboxylic acid cycle, then the enzymes are activated.
What is alosteric inhibition
Regulation of enzyme activity can be controlled by special agents - catalytic inhibitors. The stench can covalently link to the enzyme's song loci, bypassing the active site. It is necessary to cause deformation of the spacious structure of the catalyst and automatically cause a decrease in enzymatic powers. In other words, there is an alosteric regulation of enzyme activity. Dodamo also, that such a form of catalytic injection is powerful for oligomeric enzymes, that is, whose molecules are composed of two or more protein polymeric subunits. Looking at the front heading, the PDH-complex can be found in three oligomeric enzymes: pyruvate dehydrogenase, dehydrolipoyl dehydrogenase and hydrolipoyl transacetylase.
Regulatory enzymes
Studies in enzymology have established those that should be deposited both in terms of concentration and activity of the catalyst. The most common metabolic pathways are the smut enzymes that regulate all yoga areas.
The stinks are called regulators and sing on the cob reactions of the complex, and they can also take part in chemical processes, which most often proceed in irreversible reactions, or they come to the reagents at the points of breakdown of the metabolic pathway.
How does peptide interaction work
One of the ways, for the help of which is the regulation of the activity of enzymes in cells, is the protein-protein interaction. What is the language about? It is necessary to add regulatory proteins to the enzyme molecule, as a result of which activation is expected. For example, the enzyme adenylyl cyclase is located on the inner surface of the cellular membrane and can interact with such structures as a hormone receptor, as well as with a peptide that is separated by an enzyme. Since, as a result of the hormone and receptor, the intermediate protein changes its space conformation, the way of strengthening the catalytic powers of adenylyl cyclase in biochemistry leads to activation after the advent of the protein-regulator iv.
Protomy and their role in biochemistry
This group of speeches, also called proteinkinases, hasten the transfer of the PO 4 3- anion to the hydroxo group of amino acids, which enters the peptide macromolecule. The regulation of enzyme activity in protomers will be looked at by us on the basis of protein kinase A. The third molecule is a tetramer, which is composed of two catalytic and two regulatory peptide subunits and does not function as a catalyst until chotir is attached to the regulatory cells of the protomer and cAMP molecules. The reason for the transformation of the space structure of protein-regulators, which is to cause two activated catalytic protein particles to vibrate, to cause dissociation of protomirs. As cAMP molecules are fused as regulatory subunits, the inactive protein kinase complex is re-formed to a tetramer, and the association of catalytic and regulatory peptide particles occurs. In this way, the ways of regulating the activity of enzymes are looked at to prevent their reverse nature.
Chemical regulation of enzyme activity
Biochemistry has also developed mechanisms for regulating the activity of enzymes, such as phosphorylation, dephosphorylation. The mechanism of regulation of enzyme activity in different cases is as follows: amino acid excesses of the enzyme, revenge of the OH - group, change their chemical modification after phosphoprotein phosphatases on them. In this way, correction is necessary, moreover, for some enzymes it is the cause that activates them, and for others it is inhibitory. In their own way, the catalytic powers of the phosphoprotein phosphatases themselves are regulated by the hormone. For example, animal starch - glycogen - and fat in interstitial spaces between priyomami їzhі are split in the intestinal tract, to be more precise, in the twelve colonies and in the form of glucagon - pancreatic enzyme.
This process is supported by the phosphorylation of trophic enzymes of SHKT. In the period of active etching, if it comes from the tube into the duodenum, the synthesis of glucagon is enhanced. Insulin is another enzyme of the subcutaneous layer, which is vibrated by alpha-clitins of Langerhans islands, interacting with the receptor, including the mechanism of phosphorylation of the herbal enzymes themselves.
Chastkovy proteoliz
Like Bachimo, equal regulation of enzyme activity in different species of bats. For enzymes, which are located both in the cytosol and in organoids (in blood plasma or in the intestinal tract), the method of their activation is the process of hydrolysis of CO-NH peptide bonds. Vin is necessary, shards of such enzymes are synthesized in the inactive form. In the form of an enzyme molecule, a peptide part is split, and in the structure of the modification, which is left out, an active center is added. Tse to bring to the point that the enzyme "enters the working camp", so that it becomes possible to add to the bypass of the chemical process. For example, trypsinogen, an inactive enzyme in the submucosal cavity, does not break down the proteins that are found in the duodenum. In the case of enteropeptidase infusion, proteolysis occurs. The next enzyme is activated and is now called trypsin. Chastkovy proteolysis - the process of werewolves. Vіdbuvaєtsya in such ways, as the activation of enzymes that split polypeptides, in the processes of blood glottis.
The role of the concentration of external speeches in the metabolism of cells
The regulation of the activity of the enzyme by the accessibility of the substrate was often considered by us under the subtitle "Multi-enzyme complex". The frequency of passage, which takes place at the end of the stage, is strongly deposited, in view of the fact that some molecules of the outer speech are found in the hyaloplasm or organelles of the clitin. Therefore, the speed of the metabolic pathway is directly proportional to the concentration of the speech. The more reagent molecules are present in the cytosol, the greater the flexibility of all offensive chemical reactions.
Alosteric regulation
Enzymes, the activity of which is controlled not only by the concentration of external reagents, but also by speech-effectors, are so called powerful. Zavdyaki efektoram zdijsnyuetsya regulation of activity of enzymes. Biochemistry has brought what are so often called alosteric enzymes, even more important for the metabolism of cells, shards may have an overly high sensitivity to changes in homeostasis. As an enzyme, it suppresses a chemical reaction, so that it reduces its sensitivity and is called a negative effector (ingibtor). In the proliferative type, if there is an increase in the rapidity of the reaction, there is an activator - a positive effector. The most frequent use of speech, so that reagents, like chemical interactions, play the role of activators. Kіntsev well products, scho avowed as a result of variegated reactions, behave like ingіbіtori. This type of regulation, motivated by the interrelationship of the concentration of reagents and products, is called heterotrophic.
Enzyme activity can change under the influence of various external factors. Speech that influences the activity of enzymes, signifies enzyme modulators. Modulators divide their line into two groups:
1. activators. Under the infusion, an increase in the activity of enzymes is observed. As activators, they can act as metal cations. For example, Na+ is an activator of amylase in human sinuses.
2. Inhibitors. Speech, under the influx of some, there is a change in the activity of enzymes.
Inhibitors represent a great group of speeches that are distinguished by the mechanism of inhibition.
For the trivality of the ingibing effect, the ingibtori are subdivided into:
· irreversible(Yakі in case of interaction with the enzyme, it will help to keep the enzymatic activity for good);
· werewolves(Yakі timchasovo zmenshuyut enzyme activity).
The mechanism of non-reversible inhibitors can be described by the upcoming equalities:
In + E EIn,
de EIn- a complex of an enzyme with an inhibitor, in which wines do not have catalytic powers.
As a rule, irreversible inhibitors interact with the functional groups of the active site of the enzyme. The stench covalently hound them and block them in such a manner. As a result, this enzyme interacts with the substrate.
The classic butt of irrevocable inhibitors is organophosphorus speech. Diisopropyl fluorophosphate (DFF) is found to be rich in biochemical studies. Phosphorus organics are affected by excess serine in the active center of the enzyme:
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Before the enzymes, which are located in the active center of serine, lie cholesterase, trypsin, elastase and other.
As other non-returning inhibitors, alkyl agents are widely known. They interact with SH-groups of cysteine or imidasal radicals of histidine in the active center. Mechanism of irreversible enzyme inhibition by iodoacetamide:
As alkylating agents and as non-reversible inhibitors in biochemistry, there is the stagnation of iodoacetamide, monoiodoacetate and other.
The manifestation of irrevocable victorious victoriousness is in the hands of the people's state and medicine. On a new basis, there is a stagnation of insecticides (helps to fight against coma), some medicinal preparations (anticholinesterase drugs). On their basis, the battlefield speech of the nerve-paralytic division from the group of organophosphorus slugs was created.
On the vіdmіnu vіd іnіbіtorіv nіgіbіtorіv vplyu werewolves іnіgіbіtori less than a sing іnіmіzhо hour reduce the activity of enzymes. The mechanism of the current inhibitory effect can be represented by looking at the upcoming equal reactions:
In+ E EIn
In + ES ESIn
As we see from the representations of the equal reactions, the turnaround inhibitors turn back to the enzyme or the enzyme-substrate complex. In this case, the enzyme exerts its catalytic power.
Werewolves ingibtori behind the mechanism of ingibing effect are subject to competitiveі non-competitive, yakі v_drіznyayutsya one type of one for the mechanism of inhibition of action on the enzyme.
In times of non-competitive inhibition, the inhibitor reversely attaches to the enzyme above its active site. In this case, the conformation of the active center changes, which leads to the reverse inactivation of the enzyme. Under the influence of a competitive inhibitor, there is no change in the sporidity of the enzyme for this substrate, that is. value does not change Before m, but the maximum speed of the enzymatic reaction decreases ( V max). As non-competitive inhibitors, they can act as intermediary products of speech exchange.
Molecules of competitive inhibitors show similarity with the right substrate for the enzyme. A classic example of competitive inhibitors is malonic acid, which reversely reduces the activity of the enzyme succinate dehydrogenase.
Burstinic acid Malonic acid
From the representations of the formulas, it is clear that malonic acid is really strongly reminiscent of Budova Burshtinov. Structural similarity allows malonic acid to bind to the active site of the enzyme succinate dehydrogenase. However, it is not capable of entering into a reaction that is catalyzed by this enzyme (dehydrogenation reaction). Therefore, the inhibitor comes to the active center of the enzyme, blocking the possibility of its interaction with the true substrate. In this way, under the influx of a competitive inhibitor, the sporidity of the enzyme to the substrate sharply decreases (increased value Before m), but the value does not change V max. The phenomenon of competitive inhibition can be recognized as a path of a sharp increase in the concentration of the substrate of the reaction sum.
In this way, competitive inhibitors, which act like non-competitive ones, bind to the active center of the enzyme, after which there is a sharp increase in the value Before m to the substrate, which underlies the reverse decrease in yoga activity.
As a physiologically competitive inhibitor of succinate dehydrogenase, oxalic acid acts. As can be seen from the presented baby, its intermediate product of the exchange of speeches also has the same structural similarity with succinic acid. Competitive inhibition of succinate dehydrogenase by oxalic acid plays an important role in the regulation of oxidative transformation in mitochondria:
Another type of regulation of enzyme activity - alosteric regulation. Vіn pritamanny especially group of enzymes - alosteric enzymes. Before alosteric enzymes, there are oligomeric proteins, in the structure of which there are regulatory (alosteric) centers.
The warehouse of molecules of alosteric enzymes has two types of subunits:
1) catalytic(Z);
2) regulatory (R).
The catalytic subunit is represented by a polypeptide lance, on which the active center of the enzyme is located. Regulatory subunit to take away from its structure the regulatory (alosteric) center. Alosteric center is a division of a molecule, created in a specific interaction with an enzyme regulator. Vidpovidno regulators can be both activators and inhibitors of the enzyme.
Linkage of the alosteric regulator with the regulatory center is considered to be related to the steric similarity of the molecule to the alosteric center. Depending on the geometric similarity of the surface of the regulator molecule and the trivimir structure of the alosteric center between them, there is a reverse specific interaction. A complex is established, which is stabilized by the forces of weak interactions. Van der Waals forces are of particular importance. For them, the stabilization of the regulator complex with an alosteric center takes the part of water bonds, as well as hydrophobic and electrostatic interactions.
As a result of the interaction between the enzyme and an alosteric inhibitor in the protein molecule, the conformational disruption of the polypeptide lance of the regulatory subunit is caused. Їх viniknennya is indicated on the mutual modality Z- І R- subunits. As a result, the conformation of the polypeptide lance of the catalytic subunit changes again. Similar to perebudova is accompanied by the destruction of the structure of the active center, as a result of which there is a decrease in the sporidity of the active center to the substrate (increase in the value Before m), which indicates enzyme inhibition (Fig. 33).
Malyunok 33 – Mechanism of alosteric enzyme inhibition
The addition of an alosteric inhibitor to the alosteric center leads to a change in the conformation of the active center on the catalytic subunit of the enzyme and a decrease in its sporidity to the substrate.
Alosteric inhibition by werewolves. Dissociation to the complex R-subunit with an inhibitor are accompanied by a change in the external conformation of polypeptide lancets of subunits, in consequence of which the sporadization of the active center to the substrate is
Even more often in the role of alosteric inhibitors, the product of the reaction or a metabolic pathway, in which the enzyme takes part, acts. The process of enzyme inhibition is called the product of the reaction retrongіngіbuvannyam.
Retro-inhibition is the basis of the mechanism of negative induction in the regulation of metabolic processes and improvement of homeostasis. For the new work, it is safe to keep a fast pace of various industrial products in the exchange of speeches among the clients. The butt of retro-inhibition can be the inhibition of hexokinase with the reaction product glucose-6-phosphate:
In some cases, the preference is not for the end product of the reaction, but for the end product of the process in which the reaction occurs. Retroinhibition of the enzyme E product of the process P:
de B, U, R, D - intermediate products.
In the representations of the sequence, the transformation is like an alosteric enzyme inhibitor E introduce the product to the process - R. A similar mechanism of retro-inhibition is widely seen in clitins. As an example, it is possible to induce the inhibition of the enzyme acetyl-CoA-carboxylase, which takes part in the synthesis of higher fatty acids, the end product of the synthesis of fatty acids - palmitic acid.
Analogous, al protylezhny rank to work on alosteric enzymes alosteric activators. In the presence of the activator, the enzyme has a low sporidity to the substrate. However, when linking the alosteric center with the activator, the sporidity of the catalytic center to the substrate moves, which is accompanied by the movement of the sporulation of the substrate. As an alosteric activator, a molecule often acts as a reaction substrate. Whom has a deep biological sense. In times, like in clitiny, it grows well with the substrate, keeping the inner environment in good condition is necessary for its utilization. It reaches for the activation of the enzyme, which catalyzes this transformation. An example of such activation may be the activation of glucokinase by glucose.
Alosteric enzymes, in which the substrate acts as an activator, are called homotropic. On these enzymes, a sprat of the same for the future centers binding to the substrate, yak in the fallow in the minds can win the function of the regulatory and catalytic centers of the enzyme.
How proliferation of homotropic enzymes is based on heterotropic enzymes. The rest are regulated by modulators, the structure of which is suspended in the substrate. That's why in their structures one can see that they really fight for everyday life activeі alosteric centri.
More often than not, the same alosteric enzyme appears as a result of interaction with a number of different modulators - activators and inhibitors. As a butt, you can induce the enzyme - phosphofrtokinase (PFK), as a catalyzes the onset of the reaction:
With any difference, modulators may sound their own bindings on enzyme molecules.
The kinetics of homotropic enzymes depends on the kinetics of non-alosteric enzymes. Graph of the fallowness of the dryness of the reaction to the concentration of the substrate may not be hyperbolic, but a sigmoid form (Fig. 34).
Figure 34 - Kinetics of homotropic enzymes
Tom for the rozrahunka Before m they have an unacceptable jealousy of Michaelis-Menten.
The sigmoid nature of the kinetics of alosteric enzymes in the binding is especially cooperative in nature of the interaction between the other subunits of the enzyme and the substrate. Bonding of the skin offensive molecule to the substrate with a linkage bonding due to conformational changes in the vascular subunits, which resulted in the promotion of their sporidness to the substrate.
Isoenzyme
An important value in the safe and effective transfer of exchange processes in clients may isozyme. Isoenzymes are genetically determined by multiple forms of the enzyme, which catalyze one and the same reaction, but also change the structure and physical and chemical power.
A typical enzyme, represented by isoenzymes, is lactate dehydrogenase (LDH). This enzyme catalyzes the onset of the reaction.
During electrophoresis of human blood serum, five different protein fractions appear in the blood, which can catalyze the lactate dehydrogenase reaction. In this manner, it is possible to write a story about the basis of five LDH isoenzymes (Fig. 35).
Figure 35 - Rozpodil isoenzyme LDH on electrophorerogram (electrophoresis is carried out at pH 6.8)
An important explanation of the phenomenon of isoenzyme origin may be those that isoenzymes are reduced only in enzymes - oligomeric proteins. This molecule is composed of no less than two subunits.
What is up to LDH, this enzyme is a tetramer, tobto. yoga molecule includes chotiri okremi subunit. In this case, there are two different types of LDH subunits - M-type (m'azovy) and H-type (heart). The subunit is a polypeptide lance, the structure of which is encoded by a different gene, which indicates the genetic nature of the isoenzymes. Considering those that polypeptides of subunits are products of various genes, the stench may be:
· Different amino acid warehouse (primary structure);
· Unequal physical and chemical dominance (electrophoretic roughness);
· Peculiarities of synthesis in various tissues.
Depending on their structure, isoenzymes vary by kinetics (dispersion to the substrate), peculiarities of regulation of activity, as well as localization in clitins of eukaryotes and tissue specificity in living organisms.
The tetramer structure of the LGD molecule can include different types and subunits in different splines. When the tetramer is approved, a combination of subunits is possible:
From this reason, the reason for the five isoenzymes of LDH: LDH 1 is minimal electrophoretic friability, and LDH 5 is maximum.
The LDH isoenzyme genes are expressed differently in different tissues: in the heart meat, only an H-type subunit is synthesized. Therefore, less LDH 1 is settled here, as it is shaped like a wine from this type of joints. In the liver and skeletal m'yazakh, only the M-type is synthesized. Therefore, the LDH 5 isoenzyme, which is composed exclusively of M-subunits, becomes less active and functions. In other tissues with different variability, genes are expressed that encode both H- and M-subunits. Therefore, stinks can be created by various intermediate forms of LDH isoenzymes (LDH 2 -DG 4).
Based on those that subunits are separated by the amino acid warehouse, the stench may have an unequal molecular weight and electric charge. Tse zoomovlyuє їх іх іх ії ії ії ії іnі іїї іїї ії ії іkhіchі authorities.
Krіm vіdmіnnosti fіziko-khіmіchіh power, isoenzymes strongly differ in terms of catalytic power (in terms of kinetic parameters: they are characterized by a different value of the number of wrappers ( V max) and sporidity to the substrate ( Before m), as well as sensitivity to different regulators).
So, LDH has 1 value Before m in relation to lactic acid become 0.0044 M same for LDH 5 – 0.0256 M. Sechovina shows the power of the inhibitor at least LDH 5, but does not spit on LDH 1. In this case, the LDH 1 inhibitor acts as pyruvic acid, which does not have a similar effect on LDH 5.
In this order, the isoenzymes are distinguished by structure and power, and their foundation is genetically determined. With any fault of nutrition, there should be a biological dose of isoenzymes.
In order to grow in this food, it is necessary to have mothers on the uvaz, in different cells (compartments) of cells of eukaryotes, as well as in different tissues of a rich-celled organism, it is necessary to understand the difference of the mind. They have an unequal concentration of substrata themselves and sourness. Їх is characterized by a different pH value and an ionic warehouse. Therefore, in the cells of different tissues, as well as in different compartments of the cells, the chemical transformations themselves actually occur in different minds. At the link with cym іsnuvannya іzozymenіv, scho vіdminnosti vіdminnostі in catalytic and regulatory powers, allow
1) to develop one and the same chemical transformation with the same efficiency for different minds;
2) to ensure the fine regulation of catalytic changes in a sub-department of the regulators in the most specific compartment of the tissue and other tissues.
This may be illustrated by the peculiarities of the dominance of the cytoplasmic and mitochondrial isoenzymes in carbamoyl phosphate synthase. This enzyme catalyzes the reaction for the synthesis of carbamoyl phosphate.
Carbamoyl phosphate, which is metabolized in mitochondria, under the influence of the mitochondrial isoenzyme, was given up to the process of synthesis of the sechoin, and carbamoyl phosphate, which is metabolized under the influence of the cytoplasmic isoenzyme, is then vicorated for synthesis pyrimidine nucleotides. Naturally, these enzymes, associated with various exchange processes, are divided widely and may have different catalytic and regulatory powers. Your presence in one clitin allows you to simultaneously attend two different processes, tying one successor to the victories.
In this manner, the reason for the isoenzyme in may have important biological significance, due to the possibility of overrunning the quiet enzymatic processes themselves in different minds and z ciєї the causes are genetically determined.
Control nutrition
1. What is the difference between enzymes and non-protein catalysts?
2. Reexamine the main classes of enzymes and characterize them.
3. What is the current international nomenclature of enzymes based on?
4. Give a clear understanding of the "energy barrier of the reaction."
5. How do you look at the mechanism by which enzymes lower the energy barrier of the reaction?
6. What is the reason for the physical difference of the Michaelis constant and the maximum speed of the reaction?
7. Which units have the Michaelis constant and the maximum speed of reaction?
8. Why does the increase in the temperature of the reaction sum to the temperature optimum increase the rate of enzymatic reaction?
9. How do you see the specificity of enzymes in your mind? What is the reason for the specificity of enzymes?
10. Why does the activity of enzymes depend on the pH of the medium? The activity of some enzymes in the greater world should be deposited as a factor?
11. What methods of calciferous enzyme designation do you know?
12. What is the activity of enzymes affected by?
13. What are the principles of difference between werewolves and non-reversible inhibitors?
14. What are competitive inhibitors? What competitive inhibitors do you know?
15. What is the mechanism of alosteric inhibition?
16. Why do you think the biological significance of isoenzymes is based?
17. What methods of isoenzyme fractionation do you know?
Chapter 6
Vitamins are called organic speech, which in small quantities is necessary for the normal exchange of speech and physiological functions, is not synthesized in the body by the viscous components of speech.
The need for vitamins for the safety of the life of the body is related to it, most of them take part in the development of coenzymes. Considering those who need even small amounts of enzymes to ensure the normal flow of catalytic processes, which are not yet involved in the process of chemical reactions, vitamins are also necessary for the body in even small amounts.
Ninі vіdomo over 20 vіtaminіv. The main їх dzherelami є:
· hedgehog of a creature's taroslin adventure;
saprophytic microflora of the large intestine;
Provitamin.
Provitamins they are the champions of vitamins, from which in the body there are different paths for the establishment of active vitamins. They are preceded by carotene (provitamin A), 7-dehydro-cholesterol (provitamin D) and other.
Okrim vitamins, see a special group vitamin-like speeches. Qi of speech may be the power of vitamins, but they are synthesized in the body of a person. They include carnitine, inositol, lipoic acid, choline, pangamic acid, vitamin U and in. Vitamin-like speech reveals the power of vitamins in different types of organisms.
The order of vitamins is the main group of speeches - antagonists, which are designated by the term antivitamins. Before them, one can hear speeches that show the day, the protilezhnu of the vitamins.
Antivitamins can be mentally subdivided into two groups according to the mechanism of their antivitamin effect.
1. Enzymes that destroy vitamins. Buti thiaminase (an enzyme that catalyzes the transformation of vitamin B 1), ascorbate oxidase (an enzyme that catalyzes the transformation of vitamin C), etc. can be used as an example of representatives of this group.
2. Speech, which can be similar to vitamins structure, for which building structure to enter with vitamins in a competitive position for the global business of communication. This group includes also other vitamins (oxythiamine and other).
Vitamins need to be deposited for various reasons. Before them one can see to become, century, it's time to rock, geographic latitude of living, physical state, character of practice, state of health and wellness.
In that case, if there is a violation of the vitality between the body's need for vitamins and equal yogo supply to the body, there is a vitamin imbalance. A manifestation of vitamin imbalance can be:
hypovitaminosis;
Avitaminosis;
· Hypervitaminosis.
Hypovitaminosis are becoming, for which they change in place of the vitamin in the body. Іsnuє two main groups of reasons ( outrageousі internal), yakі produce up to їх viniknennya.
1. There are reasons that lead to a decrease in the intake of vitamins in the body of the body (starvation, the introduction of products, which will avenge a small amount of vitamins or other incorrect culinary samples).
2. Internal causes of the effects of increased consumption of vitamins by the body in singing camps (children's age, vagity, important physical work, with stress and various internal illnesses) min in the body (in case of various illnesses, associated with infections shlunkovo-intestinal tract).
Hypovitaminosis may be wide. Especially often the stench stinks in the spring season.
Avitaminosisє extreme form of hypovitaminosis. The stench is characterized by the release of the same amount of vitamins from the body. The most common cause of avitaminosis is the intake of vitamins in the body from a hedgehog. Ninі tsey camp trapleyaetsya seldom dosit. It can be blamed on those contingents of people who work in extreme minds (viysk, geologists, sailors, etc.).
Hypervitaminosis are themselves become, for which zbіshuєtsya vіst vіtaminіv vіtaminіv in organіzmі. The reason for these blames is most often an increase in the intake of vitamins from hedgehog. The most characteristic is the vindication of hypervitaminosis for fat loss vitamins. It can be blamed for the trivial use of products rich in vitamins, as well as for overdose of vitamin preparations.
Classification of vitamins
The modern classification of vitamins is based on their solubility. For this reason, all vitamins are divided into:
· fat reduction- Vitamins A, D, E, K, F, Q;
· waterproofing- Vitamins of group B (B 1, B 2, B 3, B 5, B 6, B 12, B c), as well as PP, C, H and rutin.
Fat-reducing vitamins
For this group of vitamins, there is a characteristic number of powerful powers:
1. Excess isoprene molecules enter the structure of rich fat-producing vitamins. The stench unite one by one at the lance of the singing dozhina, like a rich one, in which the inconsistency of fat-producing vitamins in water and navpak is indicated - good diversity in organic retailers:
2. For the safe use of fat-reducing vitamins, it is necessary to have a sufficient amount of fatty acids in the intestines, as well as a sufficient amount of fats, like those fat-reducing vitamins, in hedgehogs.
3. Calling on those that fat-producing vitamins are indistinguishable from water, stench is carried in the body by blood for the help of special protein carriers. As a rule, the skin vitamin is transported by its carrier protein.
4. Fat-dissolving vitamins are accumulated in tissues of internal organs. Like their “depot”, the tissues of the liver are most prominent. The application of the supremacy of fat-producing vitamins can not even lead to the vindication of hypovitaminosis. For this reason, the organism, for a long time, will take care of them from its “depot”.
5. Coenzyme function is not typical for most fat-producing vitamins.
6. The biological role of fat-producing vitamins is due to the fact that stench can regulate the expression of genes.
However, regardless of the similarity, fat-reducing vitamins may be the essence of the manifestation of their biological effect.
Vitamin A
Enzymes are regulated by catalysts. Like regulators can act as a metabolite, turn it off. Separate:
- activators- Speech, which will increase the speed of the reaction;
- ingibіtori- Speech to change the speed of the reaction.
Enzyme activation. Various activators can bind either to the active center of the enzyme or behind it. Before the group of activators, ie to add the active center, put: metal ions, coenzymes, substrates themselves.
Activation behind additional metals flowing behind different mechanisms:
Metal to enter to the warehouse of the catalytic plant of the active center;
Metal from the substrate is used to establish the complex;
For the rahunok, metal is established bridges between the substrate and the active center of the enzyme.
Substrates are also activators. At the time of the increase in the concentration of the substrate, the rapidity of the reaction moves. according to the reach of the concentration of the substrate, the density does not change.
If the activator is associated with the active site of the enzyme, then it covalent modification of the enzyme:
1) partial proteolysis (collisions of proteolysis). In this way, the enzymes of the herbal channel are activated: pepsin, trypsin, chymotrypsin. Trypsin can become a pro-enzyme trypsinogen, which results in 229 excess AA. Under the action of the enterokinase enzyme, with the addition of water, it is converted to trypsin, with which the hexapeptide is split. The tretinous structure of the protein changes, the active center of the enzyme is formed, and the enzyme is transformed into the active form.
2) phosphorylation - dephosphorylation. Ex: lipase + ATP = (protein kinase) phosphorylated lipase + ADP. Tse transfer reaction, like vicorist ATP phosphate. In this case, a group of atoms is transferred from one molecule to another. Phosphorylated lipase is the active form of the enzyme.
Phosphorylase activation follows this path: phosphorylase B+ 4ATP = phosphorylase A+ 4ADP
Also, when the activator is connected, the posture is activated by the active center dissociation of the inactive complex"protein-active enzyme". For example, protein kinase is an enzyme that causes phosphorylation (cAMP-deposit). Protein kinase is a protein that has a quarter structure and is composed of 2 regulatory and 2 catalytic subunits. R 2 C 2 + 2cAMP \u003d R2 cAMP 2 + 2C. This type of regulation is called alosteric regulation (activation).
Enzyme inhibition. Іngіbіtor - tse rechovina, scho vyklikає specific decreased activity of the enzyme. The next difference between inhibition and inactivation. Inactivation - for example, protein denaturation as a result of different agents that denature.
For mіtsnistyu zv'yazuvannya inhibitors with the enzyme inhibitors can be divided into werewolves and non-returners.
Non-reversible inhibitors It is possible to bind and destroy the functional groups of the molecule to the enzyme, which is necessary to show catalytic activity. All procedures for purification of the protein should not be added to the binding of the inhibitor and the enzyme. For example: diya organophosphorus tests on the enzyme - cholesterase. Chlorophos, sarin, somant and other organophosphorus compounds bind to the active center of cholesterase. As a result, phosphorylation of the catalytic groups of the active center of the enzyme is observed. As a result, the enzyme molecules bound to the inhibitor cannot bind to the substrate and are severely disrupted.
So see werewolves for example prozerin for cholesterase. Werewolf іngіbuvannya lie in the concentration of the substrate and the inhibitor and znіmaєtsya oversubstratum.
Behind the mechanism see:
Competitive inhibition;
Non-competitive inhibition;
Substrate inhibition;
Alosteric.
1) Competitive (izosteric) inhibition- tse galvanization of the enzymatic reaction, causing the binding of the inhibitor to the active center of the enzyme. In this case, the inhibitor may be similar to the substrate. The process has competition for the active center: enzyme-substrate and inhibitor-enzyme complexes are established. E+S®ES® EP® E+P; E+I® E. Ex: succinate dehydrogenase reaction [Fig. COOH-CH 2 -CH 2 -COOH® (above the arrow SDG, pid FAD®FADH 2) COOH-CH=CH-COOH]. The right substrate for the reaction is succinate (burstinic acid). Inhibitors: malonic acid (COOH-CH 2 -COOH) and oxaloacetate (COOH-CO-CH 2 -COOH). [Mal. enzyme with 3 dirks + substrate + inhibitor = complex of inhibitor with enzyme]
Ex: cholesterase enzyme catalyzes the conversion of acetylcholine to choline: (CH 3) 3 -N-CH 2 -CH 2 -O-CO-CH 3 ® (above the XE arrow, pid - water) CH 3 COOH + (CH 3) 3 - N-CH2-CH2-OH. Competitive inhibitors are prozerin, sevin.
2) Non-competitive inhibition- galvanization, connected with the injection of an inhibitor on catalytic conversion, but not binding to the enzyme with the substrate. In this case, the inhibitor can bind both to the active center (catalytic plant) and behind it.
When an inhibitor is added to the active site, it causes the conformation (tretinous structure) of the protein to change, after which the conformation of the active center changes. The cost of the catalytic plant and the importance of interaction between the substrate and the active center. If this inhibitor is not similar to the substrate, then the inhibition cannot be taken in excess of the substrate. Possibility of establishing additional complexes of the enzyme-ingibtor-substrate. The speed of such a reaction will not be maximum.
To non-competitive inhibitors include:
Cyanide. The stench binds to the atom of the bay in cytochrome oxidase and, as a result, the enzyme loses its activity; tse enzyme of the dihal lance, which breaks down the respiratory tract and stinks.
They are important metals and their organic compounds (Hg, Pb and other). Mekhanizm їhnyoї dії poov'azaniya zі z'ednannyam їх іz different SH-groups. [Mal. enzyme with SH-groups, mercury ion, substrate. Everyone goes to the third complex]
A number of pharmacological agents, which may affect the enzymes of evil cells. Here you can see the ingibtori, who victorious in the agricultural state, pobutovі otruynі speech.
3) Substrate inhibition- Galmuvannya enzymatic reaction, viklikana oversubstratum. As a result of the establishment of the enzyme-substrate complex, which does not give in to the catalytic transformation. You can also change the concentration of the substrate. [Mal. binding to the enzyme at the same time with 2 substrates]
4) Alosteric inhibition - galvanization of the enzymatic reaction, without the addition of an alosteric inhibitor to the alosteric center of the alosteric enzyme. This type of bias is characteristic of alosteric enzymes, which form a quarter structure. As inhibitors, metabolism, hormones, metal ions, coenzymes can act.
Mechanism dії:
a) bringing the inhibitor to the alosteric center;
b) the conformation of the enzyme changes;
c) changes in the conformation of the active center;
d) the complementarity of the active site with the enzyme substrate is impaired;
e) the number of ES molecules changes;
f) change the speed of the enzymatic reaction.
[Mal. enzyme with 2 dirks, up to one alosteric inhibitor and another change the form]
To the peculiarities of alosteric enzymes, inhibition can be attributed to the negative serum binding. A®(E 1)B®(E 2) C®(E 3) D (see D arrow to arrow between A and B). D is a metabolite that acts as an alosteric inhibitor on the E1 enzyme.
Exchange of speeches
Speech exchange (metabolism)- all the combination of physiological and biochemical processes that ensure the life of the organism in mutual relations with the natural medium, directing to self-creation and self-preservation.
Before the physiological processes, one can see etching, soaking, breathing, seeing and seeing; to biochemical - chemical transformation of proteins, fats, carbohydrates, yak in organisms like savory speeches. Especially biochemical processes and those that stink zdіysnyuyutsya pіd hour low enzymatic reactions. The enzymes themselves ensure the same sequence, the time of that quickness of the reactions.
For straightening, the chemical transformation is subdivided into:
A) disimilation(catabolism) - disintegration of speech to more simple ones with the transition of the energy of speech bonds to the energy of macro-energy bonds (ATP, NAD H, in.);
b) assimilation(Anabolism) - the synthesis of more collapsible speeches with more simple ones with a lot of energy.
The biological significance of these two processes in that, from the splitting of speeches, it is laid down in some energy, which ensures all the functional capabilities of the body. At that very hour, during the disintegration of speeches, “budding materials” (monosaccharides, AA, glycerin and others.) are established, which then wink in the synthesis of speeches specific to the organism (proteins, fats, carbohydrates and others.).
[SCHEME] Above the horizontal line (near the outermost middle) - "proteins, fats, carbohydrates", above them the arrow down under the line (in the middle of the body) until the inscription "disimilation", along the rest of the chotiri arrows: two up to the inscription above the line єyu "warmth" that "kintsev products"; one arrow to the right to write "industrial speech (metabolites)", from them to "assimilation", then to "wet proteins, fats, carbohydrates"; one arrow down to the inscription "energy of ATP"; and also uphill to "warmth" and "assimilation".
Dissimilation of proteins, fats and carbohydrates flows in a different way, but in the rubble of these speeches there is a low level of inflammation:
1) Overpickling stage. In HKT, proteins are broken down to AA, fats - to glycerol and FFAs, carbohydrates - to monosaccharides. There is a large number of non-specific speeches from specific ones that need to be called. For the rahunok peretravlennya in the intestinal tract, about 1% of the chemical energy of the speeches is seen. This stage is necessary for the fact that the speeches that came to mind could get wet.
2) Stage of intermediate exchange (tissue exchange of speech, metabolism). On the clitinic level, wines are subdivided into anabolism and catabolism. Utvoryuyuyutsya and transform intermediary speeches exchange of speeches - metabolites. In this case, the monomers, which have settled down at the stage of over-etching, break up into small (up to five) key intermediate products: PIA, alpha-KG, acetyl-CoA, PVA, alpha-glycerophosphate. Up to 20% of speech energy is seen. As a rule, the intermediate exchange occurs in the cytoplasm of cells.
3) Residual decay speeches for participation sour until final products(ЗІ 2 , N 2 Oh, nitrogenous speech). You can see close to 80% of the energy of speeches.
At the same time, the stages considered are more than the main forms of exchange processes. As in the other, so in the third stages, the energy, which is seen, accumulates in the visible energy of chemical bonds in macroergic parts (there are speeches that might want one macroergic link, for example, ATP, CTP, TTP, G TF, UTF , ADP, CDP, ..., creatinphos, 1,3-diphosphoglyceric acid). So, the energy of the binding of the remaining phosphate of the ATP molecule becomes close to 10-12 kcal / mol.
The biological role of the exchange of speeches:
1. accumulation of energy during the breakup of chemical spills;
2. recovery of energy for the synthesis of the body's own speech;
3. disintegration of the cellular structural components;
4. Synthesis and decomposition of biomolecules of a special nature is expected.
Exchange of whites
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All topics of which I divided:
Proteins and their biological role
Protein (proteins) - protos - in front of the mustache, first, head, which means everything else. Proteins are high molecular weight nitrogenous organic speech.
Characteristics of simple proteins
At the basis of the classification (created in 1908) lies the diversity of whites. Behind this sign, one can see: I. histoniprotamine, rozchinnі in salt rozchini. Pro
Chromoproteins
The prosthetic part is pofarbovan (chromos - farba). Chromoproteins include hemoglobin, myoglobin, catalase, peroxidase, a number of flavin enzymes (succinate dehydrogenase, aldehydedox)
Lipid-protein complexes
Lipid-protein complexes are folding proteins, the prosthetic part of which is composed of different lipid components. The following components can be seen: 1. boundary and non-extensive B
Nucleoproteins
Nucleoproteins are collapsible proteins that can contain as little as a small fraction of nucleic acids (up to 65%). NPs are composed of 2 parts: protein (revenge histones and protamines, which
Carbohydrate-protein complexes
Like a prosthetic group, they enter into carbohydrates. All carbohydrate-protein complexes are subdivided into glycoproteins and proteoglycans. Glycoproteins (GP) - a complex of proteins with carbohydrates
Phosphoproteins
Proteins, de yak prosthetic group - phosphoric acid. The addition of phosphoric acid to the polypeptide lancet to form a folding ether link with AK SER or TPE.
Budova coenzyme
Coenzymes in catalytic reactions reduce the transport of various groups of atoms, electrons and protons. Coenzymes bind with enzymes: - covalent bonds; - ionnymi
Isoenzyme
Isoenzymes - ceofunctional proteins. The stinks catalyze one and the same reaction, but they fight for some kind of functional authority through authority over: - amino acid storage;
Dominance of enzymes
The main roles of enzymes and non-biological catalysts: 1) and others catalyze less energetically possible reactions; 2) increase the quickness of the reaction; 3) n
Nomenclature of enzymes
1) Basic trivial nomenclature - name vipadkovy, without a system of bases, for example, trypsin, pepsin, chymotrypsin. 2) Working nomenclature - the name of the enzyme is added to the name
Current findings about enzymatic catalysis
The first theory of enzymatic catalysis was put on the cob in the 20th century by Warburg and Baylis. This theory advocated that the enzyme adsorbs on its own substrate and was called adsorption, but
Molecular effects of dienzymes
1) The effect of concentration is the adsorption to lie on the surface of the molecule to the enzyme of the molecules of the reacting speeches, tobto. substratum, which should lead to the shortest interplay. Ex: electrostatic attraction
Theory of acid-base catalysis
At the warehouse of the active center of the enzyme, there are acidic, and basic functional groups. As a result of this enzyme, it acts to catalyze the acid-base power, that is. playing a role
Overpickling and soaking whites
The functions of proteins are different, but especially structural, catalytic and energy functions are seen. The energy value of the protein is close to 4.1 kcal/g. The middle of the mouthful of speeches that need to be
The transformation of whites in the organs of etching
These proteins are produced by dihydrolases (the third class of enzymes), the peptidases themselves - stinks, sound, vibrate in an inactive form, which are activated by a pathway of partial proteolysis.
Overpickling of folding proteins and their catabolism
1. Glycoproteins are hydrolyzed for the help of glycosidases (amylolitic enzymes). 2. Lipoproteins - for the help of lipolytic enzymes. 3. Hemochemical chromoprote
Rotting whites and fluffy yoga products
Decay of proteins – bacterial decay of proteinaceous tissues and AA under the intestinal microflora. Ide in the intestines, prote can be posterigatisya and in the tube - with a decrease in acidity.
Metabolism of amino acids
The AK Fund helps the organism for the proper functioning of the processes: 1) hydrolysis of proteins; 2) hydrolysis of tissue proteins (under the influence of cathepsins in lysosomes). AK-Fund is being used for the process
Zagalnі shlyakhi exchange speeches
1. Renaming (acknowledged in 1937 by Braunstein and Krizm).
Timchasovoe zneshkodzhennya ammonia
Ammonia is toxic (50 mg ammonia is injected into a rabbit, moreover = 0.4-0.7 mg / l). Therefore, in the fabrics of ammonia zneshkodzhuetsya timchasovymi ways: 1) important - image
Ornithine cycle of sechovinization
Sechovina to cover 80-90% of the total nitrogen section. For the production, 25-30 g of NH2-CO-NH2 sechovin is used. 1. NH3 + CO
Synthesis and degradation of nucleotides
Peculiarities of nucleotide exchange: 1. Ні nucleotides themselves, and nitrogenous bases, which should be present, are not included before the synthesis of nucleic acids and nucleotides in the organism. Tobto, nucleotides
Oxidation of purine nucleosides
Adenosine® (adenosine deaminase, +H2O, –NH4+) іnosine® (purine nucleoside phosphorylase, +Pn-ribosyl-1-P) hypoxanthine (6-oxopurine) ® (xanthineoxy
DC functionality
Substrate H2 → NAD → FMN → CoQ → 2b → 2c1 → 2c → 2a → 2a3 → O
Replication (self-substitution, biosynthesis) of DNA
Have 1953 r. Watson and Crick discovered the principle of complementarity (mutual complementarity). So, A \u003d T, and GC. Wash, necessary replications: 1. side
Transcription (transfer of information from DNA to RNA) and biosynthesis of RNA
During transcription, for the purpose of replication, information is transmitted from a small plot of DNA. The elementary unit of transcription is an operon (transcripton) - a DNA cell that needs to be trans.
Regulation of protein biosynthesis
Cells of a bugatoclytic organism resist the same set of DNA, but different proteins are synthesized. For example, happy tissue actively synthesizes collagen, while malignant cells do not have such a protein. At
Mechanisms for the development of cancerous swelling
Cancer is a genetic disease, that is. ushkodzhennya geneiv. See the ear of genes: 1) the loss of a gene; 2) the power of a weak gene; 3) gene activation;
Lipid overdosing
Acting like that, the lips at the empty mouth are less than mechanical work. Lipolytic enzymes in the mouth empty do not dissolve. Overpickling of lipids in the presence of quiet viddilah
Fat resynthesis mechanism
The resynthesis of fat at the intestinal wall is as follows: 1. The hydrolysis products (glycerol, VFA) are activated with additional ATP. Dalі vіdbuvaєtsya posіdovne аtsilyuvannya
Transport forms of lipids in organisms
Lipidi are indistinguishable from the water, so for the transfer of blood, special carriers are needed, which are separated from the water. Such transport forms are plasma lipoproteins.
The transformation of lipids in tissues
In tissues, the processes of disintegration and synthesis of lipids are constantly going on. The main mass of lipids in the body of a person is formed by TG, like a clitin, like an inclusion. The period of renewal of TG in different tissues
Biosynthesis of Glycerin and FFA in Tissues
The biosynthesis of glycerol in tissues is closely related to glucose metabolism, as a result of catabolism to pass through the stages of triosis. Glyceraldehyde-3-phosphate in the cytoplasm
Pathology of lipid metabolism
At the stage of nadkhodzhennya іz їzheyu. Ryasna fat hedgehog and natomist hypodynamia lead to the development of alimentary obesity. Damaged exchange may be due to insufficient dietary fat
Ioni Ca2+
Confirmed with protein - calmodulin. Ca2+-calmodulin complex activates enzymes (adenilate cyclase, phosphodiesterase, Ca2+-depleted protein kinase). Є group
Hormones of the parathyroid glands
Parat-hormone, which is composed of 84 AA, regulates the level of Ca2 +, stimulates the release of calcium (and phosphorus) from the cysts in the blood; Promote reabsorption of calcium in nirkah, but also stimulate excretion of phosphorus; Z
The role of vitamins in the exchange of speech
1.(!) vitamins are the precursors of coenzymes and prosthetic groups of enzymes. For example, B1 - thiamine - enter the warehouse of the coenzyme of ketoacid decarboxylases in TPP (TDF), B2 - riboflavin -
Understanding about hypovitaminosis, avitaminosis and hypervitaminosis
Hypovitaminosis is a pathological state, due to lack of vitamin in the body. Avitaminosis is a pathological state, caused by daily vitamin deficiency in the body.
Causes of hypotaminosis
1. First: not enough vitamin in zhy. 2. Secondary: a) decreased appetite; b) increased vitrata of vitamins; c) damage to the vmoktuvannya and disposal, for example, entero
Vitamin A
Vitamer: A1 - retinol and A2 - retinal. Clinical name: antixerophthalmic vitamin. Due to the chemical nature: cyclic non-existent monohydric alcohol on the basis of ring b-
Vitamin D
Antirachitic vitamin. There are two vitamers: D2 – ergocalciferol and D3 – cholecalciferol. Vitamin D2 is found in mushrooms. Vitamin D3 is synthesized in org
Vitamin E
Obsolete: anti-sterile vitamin, antioxidant enzyme. In the chemical plan, alpha-, beta-, gamma-delta-tocopherols, and alpha-tocopherol are more important. Vitamin E stable
Vitamin K
Antihemorrhagic vitamin. Vitamins: K1 - phylloquinone and K2 - menaquinone. The role of vitamin K in speech metabolism
pantothenic acid. [Mal. formula HOCH2-C((CH3)2)-CH(OH)-CO-NH-CH2-CH2-COOH] Combines with butyric acid and b-alanine.
Hydroxylation of xenobiotics with the participation of the microsomal monooxygenase system
1. Benzene: [Fig. benzene + O2 + NADPH2 ® (hydroxylase, cytochrome P450) phenol + NADP + H2O] 2. indole: [Fig. indole+О2+Н
The role of the liver in pigment metabolism
Pigmentary exchange is the fabrication of folded mutual transformations of the speeches of fabrics and the body of a person. There are 4 groups of speeches before pigments: 1. heme
Biosynthesis of heme
The biosynthesis of heme is found in most tissues, a few in erythrocytes, so as not to destroy mitochondria. In the human organism, heme is synthesized from glycine and succinyl-CoA, the resulting meta
Heme breakdown
The majority of hemechromogenic pigments in the body of a person are absorbed by the disintegration of heme. The head end of the heme is hemoglobin. In erythrocytes, instead of hemoglobin, become 80%, hour of life
Pathology of pigment metabolism
As a rule, it is associated with disrupted processes of heme catabolism and manifests itself in hyperbiliary rubinemia and manifests itself in yellowness of the skin and visible mucous membranes. Growing up in the central nervous system, bilirubin screaming
Tipi change the biochemical blood warehouse
I. Absolutely and visibly. Absolute mind blowing synthesis, disintegration, vision of others. Vіdnosnі vіdnosnі obumovlenі zmіnoy obyagu c
Protein storage of blood
Functions of blood proteins: 1. support oncotic pressure (importantly for albuminous cancer); 2. Vyznayut viscosity of blood plasma (mainly for albumin rahunki);
Hot white
The normal blood protein is 65-85 g/l. Zagalny protein is the sum of all protein speeches of blood. Hypoproteinemia - a decrease in albumin. Reasons:
Globulins are normal 20-30 g/l
I. α1-globulin α-antitrypsin – inhibition of trypsin, pepsin, elastase, other blood proteases. Vikonu anti-igniter
excess nitrogen
Surplus nitrogen is the sum of the nitrogen of all non-protein nitrogen-mining speeches of the blood. The norm is 14-28 mmol / l. 1. Metabolism: 1.1. amino acids (25%); 1.2. creat
Carbohydrate exchange
Glucose in the capillary blood of the body is 3.3-5.5 mmol/l. 1. Hyperglycemia (glucose elevation): 1.1. pancreatic hyperglycemia - for the duration of the stroke
Lipid exchange
Cholesterol is normal 3-5.2 mmol/l. Plasma contains LDL, LDLNS (atherogenic fraction) and HDL (anti-atherogenic fraction). Improving the development of atherosclerosis
Mineral exchange
Sodium is the main postacute ion. Mineralocorticoids (aldosterone trap sodium in blood) are added to the blood Na+ level. Sodium rhubarb increases for rahunok heme
Enzyme Plasma
Classify: 1. Functional enzymes (wet plasma). For example, renin (promoting arterial pressure through angiotensin II), cholesterase (decomposing acetylcholine). Їх activity
Physical power of the section of healthy people, their changes in pathology
I. Quantity of sections of garazd 1.2-1.5 liters. Polyuria - increase in the number of sections through: 1) increase in filtration
Indicators of the chemical warehouse section
Zagalniy nitrogen - ce sukupnіst nitrogen of all azotovіsnih rechovins in the section. The norm is 10-16 g / dobu. In case of pathologies, inhaled nitrogen can: increase - hyperazoturia
Peculiarities of speech exchange in nerve tissue
Energy exchange. In the tissue of the brain, there is an increase in clitinne dihannia (aerobic processes are overwhelmed). The brain helps to reduce more sourness, lower sirka
Chemical transmission of nervous excitement
The transfer of arousal from one cell to another depends on additional neurotransmitters: - neuropeptides; - AK; - acetylcholine; - Biogenic amines (adrenaline,
І activators that promote enzymatic activity. Inhibitors of health in interaction with enzymes with a different level of mycology. On the basis of which one the werewolf is distinguished, that non-reversible ingibuvannya. Werewolves inhibitors bind to enzymes with weak non-covalent bonds and, for singing minds, are easily water-creamed in the presence of the enzyme, for short periods of time. Werewolves ingibіtori are divided into competitive and non-competitive.
Competitive inhibitors may be structurally similar to the substrate, which is the result of the competition of molecules to the substrate and the inhibitor for binding to the active center of the enzyme. In this case, the active site interacts with the substrate, or the inhibitor, the enzyme-substrate complex (ES) or the enzyme-inhibitor (EI). p align="justify"> When molding the EI complex, the product of the reaction does not settle. The activity of the enzyme can be changed depending on the change in the concentration of the substrate. A lot of medicinal preparations act as competitive inhibitors. For example, sulfanamides, which may be bacteriostatic, are analogs of para-aminobenzoic acid, vicarious bacterium for the synthesis of folic acid (necessary for the synthesis of nucleotides and podil clitin).
Non-competitive inhibitors are not similar to the substrate, so they interact with the enzyme in the division, in the active center.
Non-reversible inhibitors establish molecular covalent bonds with the enzyme, moreover, the active center of the enzyme is often modified. In the end, this enzyme cannot override its catalytic function. For example, organophosphorus compounds covalently bind the OH-group of serine, which is in the active center and plays a key role in the process of catalysis. So іngіbіtori, as if they were victorious, like faces, to die for a long time (dobu, tizhnі). Reinvention of enzymatic activity may be due to the synthesis of new enzyme molecules.
The brument of the enzymatic processes of the Klitini is protruding over the same herd, and the feast of enzymatic reacts, the enzymatic Lantsyuga (metabolism of the noble), the yaki can be Boti Liniyni (Glikolz), and the outburst, cycles (cycles of the Krebubrebet Kryubniyi (Krebel Kryubniyi (Krebel Kryubniyi (Krebel Kryubniyi (Krebel Krebubny Krebubny. sa). To add to the speed of the metabolic pathway, it is sufficient to regulate the amount or activity of enzymes. In metabolic pathways, it is not necessary to regulate the activity of all enzymes, but the activity of key enzymes should be regulated, which means that the speed of the metabolic process is overblown.
Key enzymes є:
Enzyme cob metabolic route (first enzyme),
Enzymes that catalyze swidkist-limiting (most common) reactions,
· Enzymes, which are found in the field of metabolic pathways.
The regulation of the speed of enzymatic reactions can be influenced by:
Change the number of enzyme molecules,
Availability of molecules to the substrate and coenzyme,
· Regulation of catalytic activity of molecules of other enzymes.
Regulation of the number of molecules of the enzyme in cells can be done by changing the speed of synthesis (induction - increasing the speed of synthesis, repression - galvanization) or by changing the speed of synthesis.
An important parameter, which controls the passage of the metabolic pathway, is the presence of substrates, the main rank is the first, the higher the concentration, the more important the stability of the metabolic pathway.
Regulation of catalytic activity of other enzymes. The main methods of regulation are: alosteric and izosteric mechanisms, regulation for additional protein-protein interactions, a route of chemical modification, obmezhenny (chastkovy) proteolysis.
Isosteric mechanism. In this case, the regulator is directly injected into the active center of the enzyme. Behind such a mechanism, there are competitive inhibitors and deacons.
Alosteric mechanism. A lot of enzymes, a cream to the active center, a slightly alosteric center, ample distance from the active center. Alosteric enzymes are called oligomeric proteins, which are composed of a number of subunits. To the alosteric center, the effectors are non-covalently attached. The role can be played by substrates, end products of the metabolic pathway, coenzyme, macroergy (moreover, ATP and ADP act as antagonists: ATP activates the processes of anabolism and inhibits catabolism, ADP - navpaki).
Alosteric centers in the enzyme can be a sprinkling. Alosteric enzymes have the power of positive and negative cooperativity. The interaction of the effector with the alosteric center leads to a subsequent cooperative change in the conformation of all subunits, which leads to a change in the shape of the active center, which decreases or increases the sporidity to the substrate, and, apparently, changes either increased catalytic activity of the enzyme.
Intramolecular interaction of proteins - proteins(only for oligomeric enzymes) from a change in oligomerism. ProteinkinaseA is an enzyme that phosphorylates proteins for the ATP metabolism, it consists of 4 subunits of two types: two regulatory subunits and two catalytic subunits. This tetramer does not have catalytic activity. During the dissociation of the tetrameric complex, two catalytic subunits change and the enzyme becomes active. Such a mechanism of regulation is brutal. The association of regulatory and catalytic subunits of protenkinase A is re-formed to the inactive complex.
chemical modification Most often, the mechanism of regulation of enzyme activity in the way of covalent modification of amino acid residues is discussed. With this modification, OH-groups are added to the enzyme. Phosphorylation is controlled by protein kinase enzymes for ATP. The addition of an excess of phosphoric acid leads to a change in catalytic activity, with which the result can be twofold: some enzymes are activated during phosphorylation, while others become less active. The change in activity by way of phosphorylation is reversed. Removal of excess phosphoric acid and protenphosphatases.
Regulation of enzyme activity in a way fried proteolyse. Active enzymes are synthesized as inactive precursors - proenzymes and are activated as a result of the hydrolysis of one or more peptide links, which stimulates the splitting of a part of the protein molecule to the proenzyme. As a result, in a part of the protein molecule that is missing, a conformational change occurs and an active center is formed, and the enzyme becomes active. The cleavage of the peptide in the form of protein precursors catalyzes peptidase enzymes.
In this enzyme, the activity of the enzyme changes irrevocably. Proteolytic changes underlie the activation of proteolytic enzymes in SHKT, proteins in the blood pharynx system and fibrinolysis system, as well as protein-peptide hormones. For example, trypsinogen, which is synthesized in the submucosal cavity, is found in the intestines, where the enteropeptidase enzyme is added. As a result, proteolytic cleavage from the cleavage of the hexapeptide was observed. With this, an active center is formed in a part of the molecule and active trypsin is established.