Module 15: Enzymes
Enzymes: are biological catalysts produced by the activity of living organisms as such as plants, animals & microorganisms and which modify the speed of a reaction without being used up or appearing as one of the end products.
Wilhelm Kühne: The name enzyme was suggested in 1867 by?
Wilhelm Kühne: Father of enzymology
en zyme: Enzymes is derived from the Greek phrase?
“to enliven”: en zyme means?
Enzymology: The branch of science that focuses on the study of enzymes
Proteins: all enzymes isolated and studied were proven to be
Enzymes: In general, they are soluble in water, glycerol and dilute alcohol.
Amphoteric: Enzymes are characterized by this term which means they can react both as an acid and as a base, thus do not effect the acid-base balance of our body.
Reversible: The reactions catalyzed by enzymes are frequently?
Cofactor: It is a non protein chemical compound or metallic ion that is required for an enzyme’s activity as a catalyst considered as “helper molecules” that assist in biochemical transformations
pro-enzyme or zymogen: Some enzymes are synthesized from its inactive precursor called?
Zymogen: it is the other term for pro-enzyme a biologically inactive substance which is metabolized into enzymes
Enzymes: They are biological catalysts produced by the activity of living organisms such as plants, animals & microorganisms and which modify the speed oof reaction without being used up or appearing as one of the end prodcucts
Digestion: digest and makes food small enough to be absorbed into the blood through the intestinal walls and be distributed efficiently throughout the body.
Detoxification: It is a use of enzymes that refers to the process of eliminating unwanted or poisonous substances from the body.
Nourishment: nourish the body with vitamins and minerals. Without enzymes, vitamins and minerals will be useless or merely be excreted out from the body.
Immunity: make up every aspect of the immune system. White blood cells are merely trucks transporting enzymes that actually do all the work of healing the body and preventing diseases.
Substrate: It is the term used to denote the substance acted upon by an enzyme.
“ase”: The suffix is added to the name of the substance acted upon.
Amylase: act on starch (amylum)
Maltase: act on maltose
Cellulase: act on cellulose
Urease: acts on urea
Lipase: acts on fats (lipids)
Oxidase: for oxidation
Decarboxylase: It is the name of an enzyme that catalyzes the chemical reaction that removes a carboxyl groupand releases CO2 (decarboxylazation)
Transaminase: It is the name of an enzyme that catalyzes transfer of amino group between an amino acid and an alpha keto acid
Transamination: refers to the removal of the amino group that begins with the transfer of this amino group to an amino group acceptor, usually alpha ketoglutarate that eventually turns into glutamate.
Hydrolase: This enzyme catalyzes chemical reactions involving the breaking of complex molecules into simpler ones with the addition of water
Hydrase: An enzyme that catalyzes the addition of water.
dehydrase: An enzyme that catalyzes the removal of water
Immunity: It is the use of enzymes coming from WBC that actually do all the work of healing the body and preventing diseases
Lactate dehydrogenase: An enzyme that catalyzes removal of hydrogen atoms from lactate ions
Pyruvate decarboxylase: An enzyme that catalyzes removal carboxyl groups from pyruvate
International Union of Biochemistry Enzyme Commission: What is IUBEC
International Union of Pure and Applied Chemistry: What is IUPAC
E.C. 2.6.1.2: E.C. number for Alanine aminotransferase
E.C. 4.2.1.1: Carbonic anhydrase
trypsin: It is the trivial name of an enzyme that helps digest proteins found in pancreatic juice
rennin: An enzyme that coagulates or curds milk used in making cheese and junkets especially
International Union of Biochemistry Enzyme Commission (IUBEC): instituted a systematic classification scheme of enzymes according to the type of chemical reactions they catalyze.
OXIDOREDUCTASES: enzymes that bring about oxidation and reduction.
TRANSFERASES: enzymes that catalyze the transfer functional groups from one molecule to another.
HYDROLASES: enzymes that bring about hydrolysis, a chemical reaction that involves the breaking of complex molecules into simpler ones with the addition of water.
DESMOLASES or LYASES: enzymes that catalyze the addition of a group to a double bond or the removal of a group
LIGASES: enzymes that catalyze condensation or joining of two substrate molecules.
ISOMERASES: enzymes that rearrange the functional groups within a molecule and catalyze the conversion of one isomer to another.
Mutases: These are isomerases that catalyze the movement of a functional group from one position to another within the same molecule. In other words, those enzymes that catalyze intramolecular group transfers
PLASMA SPECIFIC ENZYMES: They are enzymes secreted by the liver into the plasma. They exert certain functions in the plasma like:
NON PLASMA SPECIFIC ENZYMES: They are enzymes that do not specific functions in the plasma since they do not have activators or coenzymes in the plasma.
Enzymes of Secretion: they are normally secreted in the plasma at a very high rate but are rapidly disposed off to normal excretory channels thus concentration in plasma is maintained at a low and constant level.
Enzymes associated with Cellular Metabolism: they are enzymes that carry out their functions within cells in which they are formed.
UNILOCULAR ENZYMES: enzymes that are found only in one location, particularly the cell sap.
BILOCULAR ENZYMES: enzymes that are found in the mitochondria and the cell sap
Enzyme variants: refer to the several distinct forms of enzymes that are important in the diagnosis of enzyme specificity as implied by their characteristics.
Isoenzymes: are multi-chained enzymes of similar activity typically appearing in specific tissues, organs and cell organelles of organisms with the same species.
Isoenzymes: They are specifically located in tissues. The site of a specific isoenzyme is found and restricted to only one tissue.
Isoenzymes: They are charged molecules that can move in an ion exchange resin
Isoenzymes: They respond to activation and inhibition processes
Isoenzymes: They have relative substrate specificities
Alloenzymes: They are genetically transmitted enzymes
Alloenzymes: Important in defining the biochemical characteristics of an individual
Alloenzymes: They are present only in some selected individuals of the same species
Alloenzymes: Practical value in forensic medicine and genetics
HETEROENZYMES: are those with the same enzymatic activity which are specific for different biological species.
Catalase: It is a common oxidoreductase found in nearly all living organisms exposed to oxygen which catalyzes the decomposition of hydrogen peroxide to water and oxygen.
Proteolytic enzymes: They refer to enzymes that work best in acidic conditions like pepsin and gastrin.
Enzyme coenzyme systems: other name for Complex enzyme action
Complex enzyme action: is more complex than the first. This system involves the presence of coenzymes, which function by assisting the enzyme in acting as an acceptor for one of the reaction products.
Apoenzyme: It is the caralytically inactive protein part to which coenzyme attaches itself
Lipase: It is the enzyme that catalyzes the hydrolysis or digestion of fats
Coenzyme: This are enzymes whose metal ions are intrinsically part of the molecule
Allosteric sites: It is a site that allows molecules to either activate or inhibit enzyme activity.
Holoenzyme: It is the catalytically active combination of the apoenzyme and coenzyme.
ABSOLUTE specificity: it is a type of enzyme specificity that occurs when the enzyme acts on a one and only substrate.
GROUP or RELATIVE specificity: it is a type of enzyme specificity that occurs when an enzyme can act on several substrates with related structure but at different intensities.
LINKAGE specificity: it is a type of enzyme specificity that occurs when an enzyme catalyzes the formation or breakage of only certain bonds in a molecule.
STEREOCHEMICAL specificity: it is a type of enzyme specificity that occurs when an enzyme can act on only a substance with specific configuration.
LOCK AND KEY MODEL: this model was devised by Emil Fischer in 1894 that refers to the rigid active site of an enzyme being complementary to the shape and size of only one kind of substrate.
Emil Fischer: LOCK AND KEY MODEL was devised by?
INDUCED FIT MODEL: it is proposed by Daniel Koshland Jr. in 1956 stating that some enzymes can probably change their size and shape when binding with their substrates.
INDUCED FIT MODEL: This model is more acceptable because the protein molecule is flexible enough to allow conformational changes and also allows some explanation on the influence of hormones on enzymatic activity
Daniel Koshland Jr: INDUCED FIT MODEL is proposed by
point of equilibrium: As the products of the reaction increase in amount, the reaction approaches the? and therefore the rate decreases.
37 to 40 0C: Enzymes of animal origin have an optimum temperature of inactivation and destruction
ENERGY: this refers to the amount of energy needed to activate an enzyme to catalyze a certain chemical reaction
MOLECULAR COMPATIBILITY: commonness or sameness between an enzyme and a substrate
SPACE AVAILABILITY: refers to the number of enzymes or substrates that can be reacted
SPECIFICITY: refers to the particular enzyme catalyzing a specific substrate
SUBSTRATE CONCENTRATION: Other conditions being kept constant, an increase in the concentration of the substrate will increase the rate of activity.
ENZYME CONCENTRATION: Using a highly purified enzyme, the velocity of the reaction is directly proportional to the concentration of the enzymes.
pH LEVEL(Hydrogen Ion Concentration): Each enzyme requires a definite pH zone. This has been discussed under characteristics of enzyme action.
TEMPERATURE: For each enzyme there is an optimum temperature for maximal activity. This has been discussed under characteristics of enzyme action.
COFACTOR CONCENTRATION: The absence of diminution in the amount of co-factors (coenzymes, activators, inorganic ions) for enzymes requiring their presence for activity will therefore decrease the rate. In some cases however, an excess of the co-factors will inactivate the enzyme.
PRODUCTS OF THE REACTION: As the products of the reaction increase in amount, the rate of enzyme activity decreases. This is due to the consumption of the substrate, the reaction that changes equilibrium, changes in pH by products formed and/or inhibition of enzymes by products formed.
TIME: The rate of enzyme action may decrease as the reaction proceeds. This factor is dependent also on the same factors influencing products of reaction.
RADIATION: In general, enzymes tend to be inactivated by light, although amylase of saliva is activated by red and green light. Ultra-violet light is very destructive; it has a denaturing effect on proteins. The beta and gamma rays of radium emanations have also destructive effects.
PRESENCE OF INHIBITORS: These substances may decrease the rate of enzyme reaction
COMPETITIVE INHIBITION: This is brought about by the presence of substances closely resembling the substrate in structure or having a similar group or radical in their molecule, so that they unite with the enzyme, thus competing with the natural or real substrate.
NON COMPETITIVE INHIBITION: This is brought about by the presence of substances that bring about chemical changes in the enzyme.
Oxidation reduction effect: The sulfhydryl radical (SH) in many enzymes when oxidized to disulfide by removal of hydrogen, renders the enzyme inactive.
Formulation of substances: resulting from the action of the inhibitors on the co-factors of the enzyme. This means that the inhibitor reacted with the coenzyme, prosthetic group of the enzyme or iron activator.
Heavy metals: probably precipitate the enzymes, thus, rendering them inactive.
UNCOMPETITIVE INHIBITION: This is brought about by the attachment of an inhibitor to an enzyme substrate complex and hinders the formation of the product.
REVERSIBLE INHIBITION: it is where inhibitors are possibly removed from the system and the enzyme is fully restored. Physical separation processes like dialysis and gel filtration can remove the inhibitors.
IRREVERSIBLE INHIBITION: it is when inhibitors combine covalently with the enzyme. Thus, physical methods are ineffective in separating inhibitors from the enzymes.
Enzymes: are biological catalysts produced by the activity of living organisms as such as plants, animals & microorganisms and which modify the speed of a reaction without being used up or appearing as one of the end products.
Wilhelm Kühne: The name enzyme was suggested in 1867 by?
Wilhelm Kühne: Father of enzymology
en zyme: Enzymes is derived from the Greek phrase?
“to enliven”: en zyme means?
Enzymology: The branch of science that focuses on the study of enzymes
Proteins: all enzymes isolated and studied were proven to be
Enzymes: In general, they are soluble in water, glycerol and dilute alcohol.
Amphoteric: Enzymes are characterized by this term which means they can react both as an acid and as a base, thus do not effect the acid-base balance of our body.
Reversible: The reactions catalyzed by enzymes are frequently?
Cofactor: It is a non protein chemical compound or metallic ion that is required for an enzyme’s activity as a catalyst considered as “helper molecules” that assist in biochemical transformations
pro-enzyme or zymogen: Some enzymes are synthesized from its inactive precursor called?
Zymogen: it is the other term for pro-enzyme a biologically inactive substance which is metabolized into enzymes
Enzymes: They are biological catalysts produced by the activity of living organisms such as plants, animals & microorganisms and which modify the speed oof reaction without being used up or appearing as one of the end prodcucts
Digestion: digest and makes food small enough to be absorbed into the blood through the intestinal walls and be distributed efficiently throughout the body.
Detoxification: It is a use of enzymes that refers to the process of eliminating unwanted or poisonous substances from the body.
Nourishment: nourish the body with vitamins and minerals. Without enzymes, vitamins and minerals will be useless or merely be excreted out from the body.
Immunity: make up every aspect of the immune system. White blood cells are merely trucks transporting enzymes that actually do all the work of healing the body and preventing diseases.
Substrate: It is the term used to denote the substance acted upon by an enzyme.
“ase”: The suffix is added to the name of the substance acted upon.
Amylase: act on starch (amylum)
Maltase: act on maltose
Cellulase: act on cellulose
Urease: acts on urea
Lipase: acts on fats (lipids)
Oxidase: for oxidation
Decarboxylase: It is the name of an enzyme that catalyzes the chemical reaction that removes a carboxyl groupand releases CO2 (decarboxylazation)
Transaminase: It is the name of an enzyme that catalyzes transfer of amino group between an amino acid and an alpha keto acid
Transamination: refers to the removal of the amino group that begins with the transfer of this amino group to an amino group acceptor, usually alpha ketoglutarate that eventually turns into glutamate.
Hydrolase: This enzyme catalyzes chemical reactions involving the breaking of complex molecules into simpler ones with the addition of water
Hydrase: An enzyme that catalyzes the addition of water.
dehydrase: An enzyme that catalyzes the removal of water
Immunity: It is the use of enzymes coming from WBC that actually do all the work of healing the body and preventing diseases
Lactate dehydrogenase: An enzyme that catalyzes removal of hydrogen atoms from lactate ions
Pyruvate decarboxylase: An enzyme that catalyzes removal carboxyl groups from pyruvate
International Union of Biochemistry Enzyme Commission: What is IUBEC
International Union of Pure and Applied Chemistry: What is IUPAC
E.C. 2.6.1.2: E.C. number for Alanine aminotransferase
E.C. 4.2.1.1: Carbonic anhydrase
trypsin: It is the trivial name of an enzyme that helps digest proteins found in pancreatic juice
rennin: An enzyme that coagulates or curds milk used in making cheese and junkets especially
International Union of Biochemistry Enzyme Commission (IUBEC): instituted a systematic classification scheme of enzymes according to the type of chemical reactions they catalyze.
OXIDOREDUCTASES: enzymes that bring about oxidation and reduction.
TRANSFERASES: enzymes that catalyze the transfer functional groups from one molecule to another.
HYDROLASES: enzymes that bring about hydrolysis, a chemical reaction that involves the breaking of complex molecules into simpler ones with the addition of water.
DESMOLASES or LYASES: enzymes that catalyze the addition of a group to a double bond or the removal of a group
LIGASES: enzymes that catalyze condensation or joining of two substrate molecules.
ISOMERASES: enzymes that rearrange the functional groups within a molecule and catalyze the conversion of one isomer to another.
Mutases: These are isomerases that catalyze the movement of a functional group from one position to another within the same molecule. In other words, those enzymes that catalyze intramolecular group transfers
PLASMA SPECIFIC ENZYMES: They are enzymes secreted by the liver into the plasma. They exert certain functions in the plasma like:
NON PLASMA SPECIFIC ENZYMES: They are enzymes that do not specific functions in the plasma since they do not have activators or coenzymes in the plasma.
Enzymes of Secretion: they are normally secreted in the plasma at a very high rate but are rapidly disposed off to normal excretory channels thus concentration in plasma is maintained at a low and constant level.
Enzymes associated with Cellular Metabolism: they are enzymes that carry out their functions within cells in which they are formed.
UNILOCULAR ENZYMES: enzymes that are found only in one location, particularly the cell sap.
BILOCULAR ENZYMES: enzymes that are found in the mitochondria and the cell sap
Enzyme variants: refer to the several distinct forms of enzymes that are important in the diagnosis of enzyme specificity as implied by their characteristics.
Isoenzymes: are multi-chained enzymes of similar activity typically appearing in specific tissues, organs and cell organelles of organisms with the same species.
Isoenzymes: They are specifically located in tissues. The site of a specific isoenzyme is found and restricted to only one tissue.
Isoenzymes: They are charged molecules that can move in an ion exchange resin
Isoenzymes: They respond to activation and inhibition processes
Isoenzymes: They have relative substrate specificities
Alloenzymes: They are genetically transmitted enzymes
Alloenzymes: Important in defining the biochemical characteristics of an individual
Alloenzymes: They are present only in some selected individuals of the same species
Alloenzymes: Practical value in forensic medicine and genetics
HETEROENZYMES: are those with the same enzymatic activity which are specific for different biological species.
Catalase: It is a common oxidoreductase found in nearly all living organisms exposed to oxygen which catalyzes the decomposition of hydrogen peroxide to water and oxygen.
Proteolytic enzymes: They refer to enzymes that work best in acidic conditions like pepsin and gastrin.
Enzyme coenzyme systems: other name for Complex enzyme action
Complex enzyme action: is more complex than the first. This system involves the presence of coenzymes, which function by assisting the enzyme in acting as an acceptor for one of the reaction products.
Apoenzyme: It is the caralytically inactive protein part to which coenzyme attaches itself
Lipase: It is the enzyme that catalyzes the hydrolysis or digestion of fats
Coenzyme: This are enzymes whose metal ions are intrinsically part of the molecule
Allosteric sites: It is a site that allows molecules to either activate or inhibit enzyme activity.
Holoenzyme: It is the catalytically active combination of the apoenzyme and coenzyme.
ABSOLUTE specificity: it is a type of enzyme specificity that occurs when the enzyme acts on a one and only substrate.
GROUP or RELATIVE specificity: it is a type of enzyme specificity that occurs when an enzyme can act on several substrates with related structure but at different intensities.
LINKAGE specificity: it is a type of enzyme specificity that occurs when an enzyme catalyzes the formation or breakage of only certain bonds in a molecule.
STEREOCHEMICAL specificity: it is a type of enzyme specificity that occurs when an enzyme can act on only a substance with specific configuration.
LOCK AND KEY MODEL: this model was devised by Emil Fischer in 1894 that refers to the rigid active site of an enzyme being complementary to the shape and size of only one kind of substrate.
Emil Fischer: LOCK AND KEY MODEL was devised by?
INDUCED FIT MODEL: it is proposed by Daniel Koshland Jr. in 1956 stating that some enzymes can probably change their size and shape when binding with their substrates.
INDUCED FIT MODEL: This model is more acceptable because the protein molecule is flexible enough to allow conformational changes and also allows some explanation on the influence of hormones on enzymatic activity
Daniel Koshland Jr: INDUCED FIT MODEL is proposed by
point of equilibrium: As the products of the reaction increase in amount, the reaction approaches the? and therefore the rate decreases.
37 to 40 0C: Enzymes of animal origin have an optimum temperature of inactivation and destruction
ENERGY: this refers to the amount of energy needed to activate an enzyme to catalyze a certain chemical reaction
MOLECULAR COMPATIBILITY: commonness or sameness between an enzyme and a substrate
SPACE AVAILABILITY: refers to the number of enzymes or substrates that can be reacted
SPECIFICITY: refers to the particular enzyme catalyzing a specific substrate
SUBSTRATE CONCENTRATION: Other conditions being kept constant, an increase in the concentration of the substrate will increase the rate of activity.
ENZYME CONCENTRATION: Using a highly purified enzyme, the velocity of the reaction is directly proportional to the concentration of the enzymes.
pH LEVEL(Hydrogen Ion Concentration): Each enzyme requires a definite pH zone. This has been discussed under characteristics of enzyme action.
TEMPERATURE: For each enzyme there is an optimum temperature for maximal activity. This has been discussed under characteristics of enzyme action.
COFACTOR CONCENTRATION: The absence of diminution in the amount of co-factors (coenzymes, activators, inorganic ions) for enzymes requiring their presence for activity will therefore decrease the rate. In some cases however, an excess of the co-factors will inactivate the enzyme.
PRODUCTS OF THE REACTION: As the products of the reaction increase in amount, the rate of enzyme activity decreases. This is due to the consumption of the substrate, the reaction that changes equilibrium, changes in pH by products formed and/or inhibition of enzymes by products formed.
TIME: The rate of enzyme action may decrease as the reaction proceeds. This factor is dependent also on the same factors influencing products of reaction.
RADIATION: In general, enzymes tend to be inactivated by light, although amylase of saliva is activated by red and green light. Ultra-violet light is very destructive; it has a denaturing effect on proteins. The beta and gamma rays of radium emanations have also destructive effects.
PRESENCE OF INHIBITORS: These substances may decrease the rate of enzyme reaction
COMPETITIVE INHIBITION: This is brought about by the presence of substances closely resembling the substrate in structure or having a similar group or radical in their molecule, so that they unite with the enzyme, thus competing with the natural or real substrate.
NON COMPETITIVE INHIBITION: This is brought about by the presence of substances that bring about chemical changes in the enzyme.
Oxidation reduction effect: The sulfhydryl radical (SH) in many enzymes when oxidized to disulfide by removal of hydrogen, renders the enzyme inactive.
Formulation of substances: resulting from the action of the inhibitors on the co-factors of the enzyme. This means that the inhibitor reacted with the coenzyme, prosthetic group of the enzyme or iron activator.
Heavy metals: probably precipitate the enzymes, thus, rendering them inactive.
UNCOMPETITIVE INHIBITION: This is brought about by the attachment of an inhibitor to an enzyme substrate complex and hinders the formation of the product.
REVERSIBLE INHIBITION: it is where inhibitors are possibly removed from the system and the enzyme is fully restored. Physical separation processes like dialysis and gel filtration can remove the inhibitors.
IRREVERSIBLE INHIBITION: it is when inhibitors combine covalently with the enzyme. Thus, physical methods are ineffective in separating inhibitors from the enzymes.
