The Amino-Acid Sequence of Clupeine YI

The primary structure of the last component of clupeine, YI, was also determined by the Japanese workers, using a new method of enzymic hydrolysis with thermolysin in place of the N O acyl shift and selective chemical degradation [Ando and Suzuki, 1967 Suzuki and Ando, 1972 (2)]. 

The sequence of sixteen amino-acid residues in the C-terminal region of TNP-clupeine YI forms more than half of the total chain this was determined by the alternate action of carboxypeptidases B and A, followed finally by hydrazinolysis. 

3 During acid hydrolysis, TNP-amino acids liberate free amino acids in high yield (Oku yam A and Satake, 1960). In the present case ofTNP-alanine, free alanine was recovered in a yield of about 70%. 

Hydroiinoiysis Pro (O.iO) Amino ocid composition Argj SerjifVoj le,0 

These results are shown schematically in Fig. VIII-5, together with the time course of amino-acid liberation. Thus the amino-acid sequence at the C-terminal region was inferred as follows  

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