First step His 57 catalyzes removal of H from Ser 195 hydroxyl. The portion (the C-terminal end) of original substrate with the new amino terminus diffuses away. Ser 195's nucleophilic O attacks carbonyl C of substrate. His 57 donates H to Ser 195 O, leading to collapse of tetrahedral intermediate. Water donates H to His 57. Resulting OH attacks carbonyl of remaining substrate. His 57 donates H to N of scissile peptide bond, tetrahedral intermediate decomposes. The portion (N-terminal end) of original substrate with the new carboxylate terminus diffuses away.

First step His 57 catalyzes removal of H from Ser 195 hydroxyl. The portion (the C-terminal end) of original substrate with the new amino terminus diffuses away. Ser 195's nucleophilic O attacks carbonyl C of substrate. His 57 donates H to Ser 195 O, leading to collapse of tetrahedral intermediate. Water donates H to His 57. Resulting OH attacks carbonyl of remaining substrate. His 57 donates H to N of scissile peptide bond, tetrahedral intermediate decomposes. The portion (N-terminal end) of original substrate with the new carboxylate terminus diffuses away.

Biology: The Dynamic Science (MindTap Course List)

4th Edition

ISBN:9781305389892

Author:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Publisher:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Chapter6: Energy, Enzymes, And Biological Reactions

Section: Chapter Questions

Problem 8TYK: Which of the following statements about the allosteric site is true? a. The allosteric site is a...

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