(a)
Interpretation:
The peptides obtained from the cleavage of given peptide chain by carboxypeptidase A has to be given.
Concept introduction:
Amino acids are linked each other by peptide bonds is called protein (one or more peptide bonds). Peptide bonds are amide bonds, in which carbonyl group of one amino acid bonded to amino group of other amino acid. The chain of the protein is drawn in such a way that left end is occupied by free amino group (say N-terminal) and right side of the chain is occupied by carbonyl group (say C-terminal).
Exopeptidases cleave peptide bonds that are not at the end.
Carboxypeptidase A is an exopeptidase, which cleave the peptide bond of C-terminal amino acid except arginine and lysine.
(b)
Interpretation:
The peptides obtained from the cleavage of given peptide chain by cyanogen bromide has to be given
Concept introduction:
Amino acids are linked each other by peptide bonds is called protein (one or more peptide bonds). Peptide bonds are amide bonds, in which carbonyl group of one amino acid bonded to amino group of other amino acid. The chain of the protein is drawn in such a way that left end is occupied by free amino group (say N-terminal) and right side of the chain is occupied by carbonyl group (say C-terminal).
Cyanogen bromide cleaves the C-terminal peptide of Methionine in a peptide chain.
(c)
Interpretation:
The peptides obtained from the cleavage of given peptide chain by trypsin has to be given.
Concept introduction:
Amino acids are linked each other by peptide bonds is called protein (one or more peptide bonds). Peptide bonds are amide bonds, in which carbonyl group of one amino acid bonded to amino group of other amino acid. The chain of the protein is drawn in such a way that left end is occupied by free amino group (say N-terminal) and right side of the chain is occupied by carbonyl group (say C-terminal).
Endopeptidases cleave peptide bonds that are not at the end.
Trypsin is an endopeptidase, which cleave the C-side peptide bond of positively charged side chains such as arginine and lysine.
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Organic Chemistry (8th Edition)
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