The Preparation of Tryptic, Peptic, Thermolysin, and Cyanogen Bromide Peptides from the Acyl Carrier Protein of Escherichia coli

The peptides obtained by reaction of trypsin, pepsin, and thermolysin on the acyl carrier protein of Escherichia coli have been purified by means of ion exchange chromatography, gel filtration, and differential solubility. The tryptic peptides from performic acid-oxidized acyl carrier protein were obtained in yields from 51 to 98%. The sum of the amino compositions of the tryptic peptides accounts for the amino acid composition of the intact protein. One tryptic peptide, which contains 43 of the 77 residues in acyl carrier protein, was degraded with pepsin and the resulting peptic peptides were isolated in yields from 75 to 100%. These peptides, in addition to those from thermolysin digests of acyl carrier protein, have provided the necessary overlaps in sequence that are required to deduce a partial amino acid sequence of acyl carrier protein.