Types of Enzymes, Oxidoreductases, Transferases, Hydrolases, Lyases, Isomerases, Ligases, Synthetases, Commission on Biochemical Nomenclature

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Biocatalysis and Enzyme Biotechnology Biocatalysis and Enzyme Biotechnology - Introduction Some Research Activities Involving Enzymatic Synthesis Properties of Enzymes Parameters Affecting Enzymatic Reactions Definitions of Some Parameters used for Describing Key Properties of Enzymes Medium for Enzymes Aqueous vs Organic Solvent Selectivity of Enzymes Types of Enzymes Biomimetic Catalysts Enzymes Commonly Used in Organic Synthesis Extremozymes Cofactor Dependent Enzymes and Cofactor Regeneration Modular Enzymes Coenzymes Use of Enzymes Medical and Clinical Uses Drugs for Digestive Disorders Industrial Uses Uses of Industrial Uses Textile Industry Uses of Leather Industry Uses of Paper Industry Cellulase Free Xylanases Uses of Food Industry Isolation and Purification of Enzymes

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Your Ad Here	Types of Enzymes The enzymes that have been exploited for organic synthesis, and the reactions catalysed by each of these types are summarized in. Enzymes have been classified into the following six classes, and a standard nomenclature has been suggested for them by the 'Commission on Biochemical Nomenclature' of the 'International Union of Biochemistry. According to standard nomenclature, each enzyme is assigned' a four number code following the abbreviation EC (for Enzyme Commission). For instance, EC1.1.1.3 means an enzyme number 3 belonging to class 1 (oxidoreductase), subclass 1 and sub-subclass 1. Oxidoreductases (class 1) Oxidoreductases facilitate redox reactions involving transfer of hydrogen or oxygen atoms between molecules. They include oxidases (e^- transfer to oxygen), oxygenases (oxygen atom transfer from molecular oxygen or O₂) prexidases (e^- transfer to peroxides) and dehydrogenases (hydride transfer). Glucose oxidase (EC1.1.3.4) is a popular example of this class of enzymes.
Transferases (class 2) Transferases catalyze the transfer of an atom (other than oxygen or hydrogen) or a group of atoms like acyl-, alkyl-, glycosyl- etc. For instance, glycosyl-transferases catalyse transfer of glycosyl group, sulphotransferases catalyse transfer of sulphate group and aminotransferases catalyse transfer of amino group. Aspartate aminotransferase (EC2.6.1.1) is a suitable example of this class of enzymes. Hydrolases (class 3) Hydrolases catalyze hydrolytic reactions or their reverse reactions (condensation) and include esterases, amidases, lipases, proteases, glycosidases, etc. Amidases also help in peptide synthesis (by condensation of acid and amino groups) and esterases also help in the formation of esters (by' condensation between acid and alcohol). Similarly, glycohydrolases are used for the synthesis of glycoproteins. Most of these hydrolytic enzymes are important for' the pharmaceutical industry. Chymosin or rennin (EC3.2.3.4) is a suitable example of this class of enzymes.
Lyases (class 4) Lyases catalyze reactions involved in the removal of a group of atoms from the substrate molecule. These enzymes include aldolases, decarboxylases, dehydratases and some pectinases. Histidine ammonia lyase (EC 3.2.1.3) is a suitable example of this class. Isomerases (class 5) Isomerases catalyze the formation f isomers of substrate molecules and therefore, include epimerases, racemases, and intramolecular transferases. Xylose isomerase (EC5.3.1.5) is a suitable example of this class.	Your Ad Here
Ligases or synthetases (class 6) Ligases catalyze the formation of covalent bonds between two substrate molecules with the help of ATP or GP molecules, which provide the energy for the reaction. Glutathione synthase (EC6.3.2.3) is a suitable example of this class.

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Extraction of Enzymes Preparation of Crude Enzymes Purification of Enzymes Chromatography Adsorption Chromatography Ion Exchange Chromatography Gel Filtration Chromatography Affinity Chromatography Electrophoresis Immobilization of Enzymes or Whole Cells Techniques for Immobilization Adsorption Method Covalent Binding Method Cross Binding Method Some Reagents Used to Immobilize Enzymes by Cross Linking Entrapping Method Entrapping by Microencapsulation Requirements for Commercial use of Immobilized Enzyme Systems Enzyme Carrier Systems Some Applications of Immobilized Enzymes and Whole Cells Reactor Types Operating Strategy Stability of Immobilization and Protection of Immobilized EnzymesCells Some Examples of the Use of Immobilized Enzymes Cells Industrial Biocatalysis Biotransformation of Polyunsaturated Fatty Acids PUFAs Hydrolalse Mediated Biotransformations Oxidative Biotransformation Enzyme Engineering