Peptide Bond formation

Question 1

How does the peptide bonds are formed

Answer 1

electrophilic C=O carbon is attacked by the nucleophilic amino group on the second amino acid

peptide bond formation is a condensation /dehydration rxn, H2O leaves

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Question 2

what is the convention of drawing peptide bonds

Answer 2

drawn from N-terminus to C- terminus

N-C-C-N-C-C

Question 3

rotation in peptides

Answer 3

rotation around carbonyl carbon and the Nitrogen atom ( around peptide bonds) are restricted

rotation is possible between:

1. amino group and alpha carbon
2. alpha carbon and carbonyl carbon

Question 4

non-specific peptide bind hydrolysis

Answer 4

can be done using acid -base catalysis

Question 5

peptide bond hydrolysis at specific sites

Answer 5

in living organisms, hydrolytic enzymes such as Trypsin and Chymotrypsin is used to cleave at a specific site

Question 6

Trypsin

Answer 6

cleaves at the carboxyl end [C-terminus] of the Arginine and Lysine

Question 7

Chymotrypsin

Answer 7

cleaves at the carboxyl end of phenylalanine, tryptophan, and tyrosine