- •Federal Agency of Education tambov state university named after g.R. Derzhavin
- •Biochemistry (part I)
- •Tambov 2012
- •I. Theoretical part The subject Of biological chemistry
- •1. Chemistry of proteins
- •1.1. Methods of exctraction and purification of proteins
- •1.2. Functions of proteins
- •1.3. Amino-acid composition of proteins
- •1.4. The structural organization of proteins
- •1.5. Physical and chemical properties of proteins
- •1.6. Classification of proteins
- •1.6.1. Simple proteins
- •1. Albumins and globulins.
- •2. Protamines and histones.
- •3. Prolamins and glutelins.
- •1.6.2. Conjugative proteins
- •1. Proteins containing non-heme iron.
- •Nucleic acids
- •The structure of nucleic acids
- •Test Questions
- •2. Enzymes
- •2.1. The chemical nature of enzymes
- •2.2. The mechanism of enzymes action
- •2.3. Kinetics of enzymatic reactions
- •2.4. Enzyme properties
- •2.5. Regulation of enzyme activity
- •1. Control of the enzyme amount.
- •2. Control of enzyme activity.
- •2.1. The influence of activators and inhibitors on the enzymes.
- •2.3. Chemical modification of the enzyme.
- •2.4. Allosteric regulation.
- •2.6. Classification and nomenclature of enzymes
- •2.7. Enzymes in medicine
- •Test Questions
- •3. Vitamins
- •3.1. Fat soluble vitamins
- •3.2. Water soluble vitamins
- •Vitamin-like substances
- •Test Questions
- •4. Basic principles of biomembranes’ organisation
- •4.1. Structure and functions of membranes
- •1. Phospholipids (90%) - glycerophospholipids and sphingophospholipids:
- •4.2. Transport of substances across membranes
- •2. Facilitated diffusion
- •Test Questions
- •5. Transmembrane transduction of the hormonal signal
- •Test Questions
- •6. Introduction to metabolism
- •6.1. Stages of catabolism
- •III. A common catabolic pathway.
- •6.2. Bioenergetics
- •6.3. Organization and operation of the respiratory chain
- •6.4. Uncoupling of oxidation from phosphorylation
- •6.5. Generation of free radicals in cells
- •6.6. Reactions of the common catabolic pathway
- •6.6.1. Oxidative decarboxylation of pyruvate
- •6.6.2. Citric acid cycle
- •7. Carbohydrate metabolism
- •7.1. Digestion of carbohydrates
- •7.2. Glycogen metabolism
- •7.3. Glycolysis
- •7.4. The inclusion of fructose and galactose
- •In glycolysis
- •7.5. The shuttle mechanisms
- •7.6. Cori cycle
- •7.7. Alcoholic fermentation
- •C6h12o6 → 2 ch3chohcooh
- •7.8. Pentose phosphate pathway (hexose monophosphate shunt)
- •7.9. Gluconeogenesis
- •Synthesis of glucose from the pyruvic acid.
- •Fructose bisphosphatase
- •Glucose-6-phosphatase
- •7.10. Regulation of carbohydrate metabolism
- •Glucose → glucose-6-phosphate.
- •Pyruvate → oxaloacetate → phosphoenolpyruvate
- •7.11. Violations of carbohydrate metabolism
- •Violation of hydrolysis and absorption of carbohydrates
- •Violations of the intermediate metabolism of carbohydrates
- •Quiz Questions
- •II. Laboratory practice Laboratory work 1. The analysis of amino acids and proteins
- •1. Qualitative analysis of amino acid mixtures by thing layer chromatography method.
- •2. Colour reaction of proteins.
- •2.1. Millon’s reaction.
- •2.2. Ninhydrin’s reaction.
- •3. Reactions of precipitation of proteins.
- •3.1. Precipitation of proteins with salts of heavy metals.
- •3.3. Precipitation of proteins with the help of concentrated mineral acids.
- •3.4. Precipitation of proteins by organic acids.
- •Test questions
- •Laboratory work 2. Conjugated proteins: glycoproteins and phosphoproteins
- •1. Phosphoproteins.
- •1.1. Proof of protein component’s present in the casein hydrolyzate.
- •1.2. Proof of phosphoric acid’s presence in the casein hydrolyzate.
- •1.3. Determination of the isoelectric point of casein.
- •2.4. Proof of carbohydrate’s presence in the egg albumin.
- •Test questions
- •Laboratory work 3. Conjugated proteins: nucleoproteins and chromoproteins
- •1. Nucleoproteins
- •1.1. Isolation of deoxyribonucleoproteins from the spleen.
- •1.2. Reaction with diphenylamine.
- •2. Chromoproteins.
- •2.1. Benzidine test for hemin group of hemoglobin.
- •Test questions
- •Laboratory work 4. Enzymes
- •1. Detection of peroxidase in potatoes.
- •2. Detection of pepsin in the gastric juice.
- •3. Hydrolysis of starch by α-amylase.
- •4. Specificity of amylase and sucrase enzymes action.
- •Test questions
- •Laboratory work 5. Identifying the activity of enzymes
- •1. The influence of activators and inhibitors upon activity of enzymes.
- •1. The influence of activators and inhibitors upon α-amylase.
- •1.2. Inhibitory effect of chloride ions on dehydrogenase complex of potatoes.
- •2. Identifying the activity of α-amylase according to Wolgemut.
- •Test questions
- •Inhibitor calimine
- •Laboratory work 6. Vitamins
- •Vitamin a (vitamin a, retinol)
- •Vitamin d (calciferol)
- •3.1. Reaction with concentrated nitric acid.
- •3.2. Reaction with ferric chloride (III).
- •9.2. Reaction with methylene-blue.
- •Test questions
- •Laboratory work 7. Oxidoreductases. Common catabolic pathway
- •1. Comparison of redox-potentials of riboflavin and methylene blue.
- •2. Identifying of catalase activity according to a.N. Bach and а.I. Oparin.
- •Test questions
- •Laboratory work 8. Carbohydrate metabolism
- •2.1. Trommer’s test with copper hydroxide.
- •2.2. Discovery of fructosuria by Selivanov’s test.
- •2.3. Enzymatic method of semi-quantitative identification of glucose in urine with the help of "GlucoPhan" test strip.
- •Test questions
- •References
2.7. Enzymes in medicine
Enzymes are used as therapeutic agents:
- in their absence or deficiency (inherited or acquired);
- for the specific destruction of some metabolic products.
Enzyme |
The use of the enzyme |
Pepsin |
Disorders in digestion of proteins in the stomach |
Urease |
Removal of urea from the organism in the apparatus of "artificial kidney" |
Hyaluronidase |
Resorption of scars |
Streptokinase, urokinase |
Preventing blood clots formation during operations |
Enzymes are used in the clinic as analytical reagents.
Immobilized enzymes are often used for the analysis, which are artificially connected with the water-insoluble carrier, which increases the stability of protein catalysts.
Enzyme |
The use of enzyme |
Glucose oxidase |
Determination of glucose concentrations in blood |
Lipase |
Determination of triacylglycerols concentration in blood |
Cholesterol oxidase |
Determination of cholesterol in blood |
Analysis of the kinetics of appearance and disappearance of enzymes in the serum is used in the diagnosis.
The composition of enzymes and their tissue distribution in an adult is mainly constant and can change in diseases. Almost all of the enzymes of the organism are functioning intracellularly. When tissue is damaged intracellular enzymes appear in the serum. Such enzymes are called indicator enzymes.
By the appearance of several tissue enzymes in plasma or serum in high amounts one can conclude on the functional status and lesions of various organs.
Disease |
Enzyme
|
Myocardial infarction |
Creatine kinase, aspartate transaminase, LDH-1 |
Viral hepatitis |
Alanine transaminase, aspartate transaminase, glutamate dehydrogenase |
Pancreatic diseases |
-amylase |
Liver diseases |
Alanine transaminase, -glutamyltransferase |
Enzimopathy (synonym fermentopathy) is the common name of diseases, developing as a result of the absence or decreased activity of certain enzymes. As a result of the interdependence of metabolic pathways defect of a single enzyme often leads to a number of disorders in the metabolism.
We distinguish hereditary and acquired enzymopathy.
1. Hereditary enzimopathys are associated with genetically determined deficiency of one or more enzymes. There are more than 150 hereditary enzymopathies, which are based on gene mutations.
2. Acquired enzimopathy.
Toxic enzymopathy is a consequence of toxic effects of xenobiotics and environmental mutagens. Lead, which is contained in the transport exhaust fumes, causes a inhibition of the enzyme aminolevulinatdehydrase involved in the synthesis of heme, which manifests the development of anemia of children in the city.
Nutritional enzymopathy may be due to prolonged lack of protein in the diet, vitamin deficiency, unbalanced nutrition.