Question

What is the catalytic triad of chymotrypsin, a type of serine protease? the enzyme-cofactor-intermediate complex the amino acids serine, histidine, and aspartate the amino acids cysteine, histidine, and aspartate the enzyme-cofactor-substrate complex the amino acids serine, histidine, and glutamate

Answer 1

The correct answer is: Serine, Histidine, Aspartate

Step-by-step explanation:

The catalytic triad of an enzyme is composed of three aminoacid residues which are the most important for its catalytic activity. They are located in the catalytic site of the enzyme. In the case of chymotrypsin- a serine protease, the catalytic triad is composed by serine, histidine and aspartate (Ser-His-Asp). Serine proteases hydrolyse peptidic bonds in proteins and peptides. To do that, the histidine-which interacts with the aspartate by a hydrogen bond so its pKa increases- take a proton from the serine. Thus, deprotonated serine is able to attack the peptide bond and to perform hydrolysis.