Salmine peptides from

Chart VIII-9. The amino acid sequences of salmine AI, iridine I (a) and (b), and iridine II with demonstration of peptides obtained by enzymic hydrolyses. The symbols used are A, Arg T, tryptic peptide Tm, thermolysin peptide NP, Neutral Protease peptide NP-7-NP, redigested Neutral Protease peptide from NP-No. 7 Tm-6-NP, Neutral Protease peptide from Tm-No. 6 (from Ando and Watanabe, 1969)... 

French biochemists identified many peptides qualitatively on paper chromatograms of the partial hydrolyzates of salmine (described only as of the genus Oncor-hynchus), as also shown in Table VI-2 [Monier and Jutisz, 1954 (1,2)]. From their results, a general structure was suggested for salmine. This formula, in contrast to those described above, is composed of unique sequences of the form M-Arg j, in addition to those of M2 Arg . 

The chemical structures of these peptides were established in the usual way by quantitative amino-acid analysis and sequence analysis by a combination of chemical and enzymic methods, including dinitrophenylation, dansylation, Edman degradation, hydrazinolysis and digestion with leucine aminopeptidase and carboxypeptidases A and B. The Neutral Protease peptides of the salmine and iridine components or derivatives thus identified are listed in Table VIII-6 with their recovery values. Differences in the amino-acid sequences and amounts of the peptides obtained from iridine I aroused the suspicion that two molecular species (a and b) were present in the iridine I component. This result, as already described, was supported by observations on the thermolysin peptides of iridine I. 

To summarize for one component of salmine (S-AI) and three components of iridine (I-Ia, I-Ib and I-II) complete amino-acid sequences were deduced as shown in Chart VIII-9, from the information obtained from three sets of peptides resulting from digestion with trypsin, thermolysin, and Neutral Protease, as well as from the N- and C-terminal sequences. 

---