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  1. INSTITUTE FOR EXCELLENCE IN HIGHER EDUCATION BHOPAL Session:-2022-23 Biochemistry Assignment Directed By:- Dr.Surbhi garde Submitted By:-Namita ughade Roll No:-420101
  2. This is to certify that Namita ughade student of Institute for excellence in higher education Bhopal has completed the assignment in Enzymes and it’s classification towards the partial fulfillment of Bsc chemistry Honours degree as Prescribed by the institution. The assignment is in record of authentic work carried by her. Professor signature CERTIFICATE
  3. I have taken efforts however,it would not have been possible without the kind support and help of my teacher and Institution. I thank my god for providing me with everything that this, required in completing this assignment. I am highly indebted to my teacher Dr. Surbhi Garde Ma’am for her guidance and constant supervision. I am very thankful to everyone who supported me in this assignment. Namita ughade ACKNOWLEDGEMENT
  4. Enzymes - Introduction  Enzymes are biocatalysts present in cells that speed up biochemical reactions without getting itself destroyed in the reaction.  All types of biochemical reactions in the cell require enzymes.  Enzymes are typically proteins.  Certain types of RNAcan also serve as catalysts. These RNAmolecules are called ribozymes and DNAzymes.
  5. Institute for excellence in higher education Bhopal
  6. Nomenclature and Classification of Enzymes  Enzymes are classified according the report of a Nomenclature Committee appointed by the International Union of Biochemistry.  This enzyme commission assigned each enzyme a systematic name and a code number, called enzyme commission (EC) number. Common name Systematic name EC number : Alcohol dehydrogenase : Alcohol: NAD+ oxidoreductase : EC
  7. Nomenclature and Classification of Enzymes The code numbers, prefixed by EC, which are now widely in use, contain four elements separated by points, with the following meaning: (i) the first number shows to which of the six main classes the enzyme belongs, (ii) the second figure indicates the subclass, (iii) the third figure gives the sub-subclass, (iv)the fourth figure is the serial number of the enzyme in its sub- subclass.
  8. Nomenclature and Classification of Enzymes  Example: EC refers to the enzyme alcohol dehydrogenase (common name).  Its systematic name is alcohol : NAD+ oxido reductase.  It catalyses the oxidation of alcohol to an aldehyde or ketone.  Reaction: an alcohol + NAD+ an aldehyde or ketone + NADH + H+  First digit 1 indicates the major class oxidoreductase  Second digit 1 indicates the subclass acting on CH-OH group of donors  Third digit 1 indicates the sub-subclass NAD+ as the electron acceptor  Fourth digit 1 indicates the serial number of the enzyme alcohol dehydrogenase
  9. Enzyme - Classification  Enzymes are classified into six categories (EC number classification) by the International Union Of Biochemists (IUB) on the basis of the types of reactions that they catalyze:  EC 1 Oxidoreductases,  EC 2 transferases,  EC 3 hydrolases,  EC 4 lyases,  EC 5 ligases,  EC 6 isomerases.
  10. Classification of Enzymes 1. Oxidoreductases Enzymes involved in oxidation-reduction reactions. Eg.Alcohol dehydrogenase 2. Transferases Enzymes involved in transfer of groups from one molecule to another. Eg. Hexokinase 3. Hydrolases Enzymes that bring about hydrolysis by addition of water. Eg. Lipase 4. Lyases Enzymes that catalyze the breaking of a chemical bond through means not involving hydrolysis, and forms a double bond or adds a group to a double bond. Eg. Fumarase 5. Isomerases Enzymes involved in all kinds of isomerization reactions. Eg. Phosphohexose isomerase 6. Ligases Enzymes catalyzing the joining of two molecules with hydrolysis of ATP. Eg. Glutamine synthetase
  11. 1. Oxidoreductases  Oxidation-reduction (redox) reactions - hydrogen or oxygen atoms or electrons are transferred between molecules.  Example: dehydrogenases, oxidases, oxygenases and peroxidases EC Common name: alcohol dehydrogenase Systematic name: alcohol:NAD+ oxidoreductase
  12. 2. Transferases  These enzymes catalyse the transfer of a group between substrates  E.g: transfer of acyl, alkyl, amino, phosphate and glycosyl.  Involves transfer of amino group
  13. 3. Hydrolases  These enzymes catalyze reactions that involve the process of hydrolysis.  They break single bonds by adding water.  Some hydrolases function as digestive enzymes. CH-O-CO-R2 CH2-O-CO-R1 CH2-O-CO-R3 + CH2-O-CO-R1 CH-O-CO-R2 CH2-OH Diacylglycerol 3 R -COOH lipase OH Triacylglycerol Fatty acid H Water
  14.  Enzymes that catalyze the breaking of a chemical bond through means not involving hydrolysis, and forms a double bond or adds a group to a double bond.  Eg: Fumarase 4. Lyases
  15.  Enzymes involved in all kinds of isomerization reactions.  Example: triosephosphate isomerase and phosphoglucose isomerase 5. Isomerases
  16.  Enzymes catalyzing the joining of two hydrolysis ofATP. Eg. Pyruvate carboxylase molecules with 6. Ligases
  17. • Pineapple contains enzyme bromelain, which can digest protein (proteolytic). • Jell-O® is made of gelatin, a processed version of a structural protein called collagen found in many animals, including humans. • Collagen = big, fibrous molecule makes skin, bones, and tendons both strong and elastic. • Gelatin you eat in Jell-O ® comes from the collagen in cow or pig bones, hooves, and connective tissues. (Yummie!) Meet the Enzyme: Bromelain
  18. Meet the Enzyme: Catecholase Lemon juice and other acids are used to preserve color in fruit, particularly apples, by lowering the pH and removing the copper (cofactor) necessary for the enzyme to function. Reaction: catecholase catechol + O2 ---------- polyphenol colorless substrate brown product