You have isolated a new protease that cleaves peptide bonds on the carboxyl side of Asp and Glu. Based on the enzyme's inactivation by DIFP, you suspect that it may utilize a mechanism similar to chymotrypsin. The difference in specificity might be explained by

A.) the presence of a positively charged residue in the S1 binding pocket.

B.) the presence of a negatively charged residue in the S1 binding pocket.

C.) replacement of serine-195 with a positively charged residue.

D.) the absence of the S1 binding pocket.

Question

Caitlyn

Chemistry

2 December, 00:58

You have isolated a new protease that cleaves peptide bonds on the carboxyl side of Asp and Glu. Based on the enzyme's inactivation by DIFP, you suspect that it may utilize a mechanism similar to chymotrypsin. The difference in specificity might be explained by

A.) the presence of a positively charged residue in the S1 binding pocket.

B.) the presence of a negatively charged residue in the S1 binding pocket.

C.) replacement of serine-195 with a positively charged residue.

D.) the absence of the S1 binding pocket.

+5

Answers (1)

Know the Answer?

Sydnee Howe · Answer 1

The correct answer is A. the presence of a positively charged residue in the S1 binding pocket.

Explanation:

The S1 pocket is basically a deep hydrophobic pocket, which permit long uncharged amino acids like tryptophan and phenylalanine to fit inside chymotrypsin. B

Binding inside the S1 pocket, places the adjacent peptide bond at the active sites for cleavage.