Ch_322b_24.13

Ch_322b_24.13 - The Serine Proteases This family of enzymes...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
The Serine Proteases This family of enzymes catalyze the hydrolysis of acid derivative substrates in a general scheme that involves a serine residue in an active site. E CHCH 2 OH NH C=O serine in active site RCX O = + substrate (-HX) acylation of serine hydroxyl E CHCH 2 O CR NH C=O O bound substrate hydrolysis E CHCH 2 O CR NH C=O O + H 2 O E CHCH 2 OH NH C=O O + RCOH Three closely related digestive enzymes belong to this family: trypsin, chymotrypsin and elastase . These enzymes are produced in the pancreas of mammals as inactive precursors called zymogens . They are secreted into the small intestine where they are activated. These digestive enzymes work together to degrade polypeptide chains. ....each preferentially hydrolyzing different amide bonds.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Site-Selective Hydrolyses of Polyamides chymotrypsin : adjacent to aromatic residues elastase : adjacent to small hydrophobic residues trypsin : just past the carbonyls of basic residues in their conjugate acid forms The serine proteases: Two additional hydrolytic enzymes (that are not serine proteases) that specifically cleave off the carboxyl-terminal residue are carboxypeptidase A and B .
Background image of page 2
H-N CH-CH 2 -CO 2 - O=C N-H CH 3 -CH C=O H-N CH-CH 2 CH 2 CH 2 CH 2 NH 3 + aspartic acid alanine lysine O=C N-H CH 2 -CH (CH 3 ) 2 CH leucine C=O H-N CH-CH 2 - phenylalanine O=C N-H HOCH 2 -CH serine C=O H-N CH-CHCH 2 CH 3 CH 3 isoleucine
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 10/20/2009 for the course CHEM 322BL taught by Professor Singer during the Spring '07 term at USC.

Page1 / 12

Ch_322b_24.13 - The Serine Proteases This family of enzymes...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online