The heptapeptide sequence of amino acids, on the basis of the information provided, is to be deduced. Concept introduction: On treating a polypeptide with 2,4-dinitrofluorobenzene in basic solution, the free amino group of the N-terminal gives a nucleophilic aromatic substitution reaction, which, on hydrolysis, gives a mixture of amino acids in which the N-terminal amino acid is labeled with a 2,4-dinitrophenyl group. The C-terminal residues are identified through the carboxypeptidase enzymes. These enzymes catalyze the hydrolysis of the amide bond of the amino acid residue containing a free liberating carboxylic acid group.

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Chapter 24, Problem 23P

Interpretation Introduction

Interpretation:

The heptapeptide sequence of amino acids, on the basis of the information provided, is to be deduced.

Concept introduction:

On treating a polypeptide with 2,4-dinitrofluorobenzene in basic solution, the free amino group of the N-terminal gives a nucleophilic aromatic substitution reaction, which, on hydrolysis, gives a mixture of amino acids in which the N-terminal amino acid is labeled with a 2,4-dinitrophenyl group. The C-terminal residues are identified through the carboxypeptidase enzymes. These enzymes catalyze the hydrolysis of the amide bond of the amino acid residue containing a free liberating carboxylic acid group.

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