ENZYMES

 
  • Acrosin : Proteolytic enzyme located in acrosome of a spermatozoan.
  • Activation : Change that is induced in an amino acid before it is utilized for protein synthesis.
  • Activation energy : Energy required to initiate a reaction.
  • Active site : Region of an enzyme molecule at which binding with substrate occurs. Also known as binding or catalyst site.
  • ADPase : Adenosinediphosphatase, an enzyme that catalyses the hydrolysis of adenosinediphosphate.
  • Allosteric effector (modulator) : A small molecule that reacts with a non-binding site of an enzyme molecule and causes a change in the function of binding site of the molecule.
  • Allosteric enzyme : Any regulatory enzyme involved in end product inhibition; it possesses an allosteric site in addition to the active site.
  • Allosteric inhibitor(s) : Substances that prevent an enzyme from changing into an active form by combining with some other part of the enzyme.
  • Allosteric site : A part of an enzyme to which a specific effector or modulator can be attached.
  • Allosteric site : Part of an enzyme to which a specific effector can be attached.
  • Amylase : Enzymethat helps to convert starch into sugar.
  • Antibiotic : A chemical substance produced by a living organism (bacteria as fungi) which inhibits the growth of other microorganisms; some antibiotics are produced synthetically.
  • Apoenzyme : It refers to a protein enzyme part of an enzyme. Along with coenzyme it forms holoenzyme.
  • Apoenzyme : Protein moiety of an enzyme that determines the specificity of the enzyme reaction.
  • Apoprotein : Protein portion of a conjugated protein exclusive of prosthetic group.
  • Aporferritin : Protein found in intenstinal mucosa cells that has ability to combine with ferric ion.
  • Bio catalyst : A catalyst of organic origin, an enzyme which accelerates biochemical reactions.
  • Carotenase : An enzyme that effects hydrolysis of carotenoid compounds, used in bleaching of flour.
  • Carotene C40H56 : A red crystalline, carotenoid hydrocarbon pigment occurring widely in nature and convertible in the animal body to vitamin A.
  • Catalase : An iron-containing enzyme that catalyses the decomposition of hydrogen peroxide into water and molecular oxygen.
  • Catalysts : A compound that is able to increase the speed of reaction. Protein catalysis are called enzymes.
  • Cellulase : Enzyme capable of splitting cellulose into glucose used mainly for digestion of plant cell walls.
  • Coenzyme : It is the non-proteinaceous part of the enzyme that is loosely bound with the apo-enzyme and without their presence the enzyme can not work.
  • Coenzyme : Non-protein portion of an enzyme; without its presence, the enzyme cannot work.
  • Cofactor : It refers to an essential non-protein that gets oxidised or reduced which still remains attached to enzyme molecules.
  • Cytase : Any of several enzymes in seeds of cereals, which hydrolyse the cell wall material.
  • Denaturation : A process that causes proteins to undergo unfolding of the characteristic structure of peptide chain.
  • Enzyme substrate complex : It refers to an intermediate compound that is formed by the action of an enzyme on substrate.
  • Enzyme unit : Amount of an enzyme that will catalyse the transformation of 10-6 mole of substrate per minute.
  • Enzymes : A protein molecule produced by living cell, it catalyses a biochemical reaction by lowering the activation energy required for reaction to proceed. Discovered accidentally by Edward Buchner (1860-1917) in 1897. Enzymes are grouped into six major classes.
  • Enzymology : Scientific study of chemical nature, biological activity and biological significance of enzymes.
  • Feedback Control : It is a mechanism by which the rate of chemical reaction is inhibited by the excessive formation of product.
  •                    H2O2   H2O +  O2
  • Hydrolases : Break down large molecules into smaller ones.
  • Hydrolysis : A chemical reaction in which a complex compound is split into simpler ones by chemical addition of water.
  • Inhibitor : A substance that limits or suppresses the catalytic activity.
  • Isoinhibitors : These are the substances which are morphologically similar to the main substrate and compete with it to slow down or stop the reaction.
  • Isomerases : Catalyse rearrangement of molecular structures to form Isomers.
  • Ligases : Catalyse covalent bonding of two substrates to form a large molecule.
  • Lyases : Catalyse the cleavage of specific covalent bonds.
  • Michaells constant (Km) : Km of an enzyme is the substance concentration at which the reaction attains half of its maximum velocity.
  • Oxidoreductases : Catalyse oxidation or reduction of their substrates.
  • Pepsin : It is an enzyme secreted by cells of gastric glands. It acts as an enzyme to digest proteins.
  • Pepsinogen : Precursor of pepsin found in the stomach mucosa.
  • Peptidase : An enzyme that catalyses the hydrolysis of peptides to amino acids.
  • pH : A symbol used to indicate acidity or alkalinity, a logarithmic index for the hydrogen ion concentration in aqueous solution.
  • Riboflavin : Yellow orange, fluorescent pigment that is essential to human nutrition.
  • Transferases : Transfer specific groups from one substrate to another.
  • Trypsin : It is an enzyme of pancreatic juice. It catalyses the hydrolysis of peptide linkage in proteins and partially hydrolyses protein.