A. Signor, L. Biondi, A. Tamburro
1969
Citations
0
Influential Citations
7
Citations
Journal
European journal of biochemistry
Abstract
A new procedure for the determination of the N-terminal groups in peptides and proteins is described. The free amino-groups are allowed to react with 2-fluoro-3-nitropyridine or 2-fluoro-5-nitropyridine in slightly alkaline solution; the resulting derivatives are easily hydrolyzed in dilute hydrochloric acid in sealed tubes to give the corresponding nitropyridyl amino acids. Most of these compounds are quantitatively recovered under these conditions: in particular it is possible to estimate proline and glycine as N-terminal residues. After isolation the nitropyridyl amino acids can be estimated spectrophotometrically; in some cases it is possible to regenerate the parent amino acid by treating the derivatives with strongly alkaline solutions. The adequacy of the present techniques in relation to those of other workers was tested on insulin, lysozyme and aldolase; the advantages and peculiarities in comparison with these procedures are discussed.