Isolation and nature of intracellular alpha-aminoadipic acid-containing peptides from Paecilomyces persicinus P-10

Small intracellular peptides containing alpha-aminoadipic acid, cysteine, and a valine moiety were obtained from mycelia of Paecilomyces persicinus P-10 by ethanol or trichloroacetic acid extraction. After performic acid oxidation and ion-exchange chromatography, analysis of the peptide fractions by two-dimensional thin-layer electrophoresis and chromatography revealed the presence of three related peptides, as sulfonic acid derivatives, each containing alpha-aminoadipic acid. Each peptide was isolated in chromatographically pure form by semipreparative thin-layer electrophoresis and chromatography. The purified peptides were subjected to differential hydrolysis, dansylation, and combined dansylation-phenylisothiocyanate sequence analysis. Based on these studies, the structures of the isolated peptides were determined to be (i) glycl-delta-(alpha-aminoadipyl)-cysteinyl-beta-hydroxyvaline, (ii) glycyl-delta-(alpha-aminoadipyl)-cysteinylvaline, and (iii) delta-(alpha-aminoadipyl)-cysteinylvaline. The peptides isolated from Paecilomyces are similar to the alpha-aminoadipic acid-cysteine-valine moiety complex peptides isolated from Cephalosporium.