The amino acid sequence of the tryptic peptides of the f1 bacteriophage coat protein : a thesis submitted to Massey University of the Manawatu in partial fulfilment of the requirements for the degree of Master of Science in Biochemistry

Abstract

Five major peptides were isolated by paper electrophoresis from a tryptic digestion of purified fl bacteriophage coat protein. The amino acid composition of the peptides was determined and shown to be:- T1 Ala2, Glu1, Asp2, Pro1, G1yl, Lys1. T2 Al1, Ser1.T3 Phe1, Thr1, Ser1, Lys1. T4 Leu1, Phe1, Lys1. T5 Lys1. Sequential degradation of the intact fl coat protein using the Edman technique showed the N-terminal sequence to be:- Ala - Glu - Gly - Asp - Asp - T1:- The sequence of the tryptic peptide T1 indicated it was derived from the N-terminal of the protein and was assigned the sequence:- Ala - Glu - Gly - Asp - Asp - (Pro1,Ala1) - Lys. T2:- After two cycles of the Edman degradation reaction the sequence of T2 was shown to be:- Ala - Ser Digestion of the intact f1 coat protein with carboxypeptidase A indicated T2 was the C-terminal peptide since carboxypeptidase A showed the C-terminal sequence to be:- - Lys - Ala - Ser T3:- Thin peptide was shown to have the sequence:- Phe - Thr - Ser - Lys T4:- This peptide was assigned the sequence Leu - Phe - Lys T5:- T5was shown be a free Lys residue.