Enzymes are selective. Active site Lock-and-key model Enzyme Enzyme A Induced-fit model Enzyme Enzyme 包 12
Enzymes are selective. 12 Lock-and-key model Induced-fit model
Enzymes decreases activation energy. Transition state G △Gad uncatalyzed AGcatalyzed Substrate △Greaction Product Progress of the reaction 13
Enzymes decreases activation energy. 13
International classification of enzymes No. Class Type of reaction catalyzed 1 Oxidoreductase Transfer of electrons 2 Transferase Group transfer reaction 3 Hydrolase Hydrolysis reaction 4 Lyase Addition of groups to double bonds,or formation of double bonds by removal of groups 5 Isomerase Transfer of groups within molecules to yield isomeric forms 6 Ligase Bond formation coupled with ATP hydrolysis Serine endopeptidase: Chymotrypsin EC3.4.21.1 Trypsin EC3.4.21.4 Subtilisin EC3.4.21.62 14
14 No. Class Type of reaction catalyzed 1 Oxidoreductase Transfer of electrons 2 Transferase Group transfer reaction 3 Hydrolase Hydrolysis reaction 4 Lyase Addition of groups to double bonds, or formation of double bonds by removal of groups 5 Isomerase Transfer of groups within molecules to yield isomeric forms 6 Ligase Bond formation coupled with ATP hydrolysis International classification of enzymes Serine endopeptidase: Chymotrypsin Trypsin Subtilisin …… EC 3.4.21.1 EC 3.4.21.4 EC 3.4.21.62
Enzyme kinetics 15
Enzyme kinetics 15
A→P First order reaction v=k[A] Zero order reaction v=k A+B→P Second order reaction =[A][B] 16
16 A → P First order reaction Zero order reaction Second order reaction A + B → P v = k[A] v = k v = k[A][B]