Which pancreatic protease cleaves after small, neutral residues?

Prepare for your Anatomy and Physiology II Exam with our comprehensive exam resources. Utilize flashcards, multiple choice questions with hints, and detailed explanations. Boost your readiness for success!

Multiple Choice

Which pancreatic protease cleaves after small, neutral residues?

Pancreatic proteases have distinct substrate preferences based on the active-site environment. Elastase has a relatively small, shallow S1 pocket that can accommodate only small side chains, so it preferentially cleaves after small neutral amino acids such as alanine and glycine. This specificity distinguishes elastase from the others: trypsin targets positively charged residues (lysine and arginine) because of a negatively charged pocket that binds those side chains; chymotrypsin prefers bulky hydrophobic residues (phenylalanine, tyrosine, tryptophan) due to its deep hydrophobic pocket; carboxypeptidases act as exopeptidases at the C-terminus rather than cleaving internal peptide bonds. Therefore, elastase is the enzyme that cleaves after small, neutral residues.

Pancreatic proteases have distinct substrate preferences based on the active-site environment. Elastase has a relatively small, shallow S1 pocket that can accommodate only small side chains, so it preferentially cleaves after small neutral amino acids such as alanine and glycine. This specificity distinguishes elastase from the others: trypsin targets positively charged residues (lysine and arginine) because of a negatively charged pocket that binds those side chains; chymotrypsin prefers bulky hydrophobic residues (phenylalanine, tyrosine, tryptophan) due to its deep hydrophobic pocket; carboxypeptidases act as exopeptidases at the C-terminus rather than cleaving internal peptide bonds. Therefore, elastase is the enzyme that cleaves after small, neutral residues.

More practice questions