Presence of δ-( l -α-Aminoadipyl)- l -Cysteinyl- d -Valine in Fermentations of Penicillium chrysogenum

Abstract

Cultures of Penicillium chrysogenum , growth with [ 35 S]sulfate or labeled amino acids, were examined by ion-exchange chromatography for possible peptidic precursors of penicillin. A sulfur-containing compound, present in both the mycelial extracts and the culture filtrates, was eluted at the location of the synthetic lld -tripeptide δ-( l -α-aminoadipyl)- l -cysteinyl- d -valine. Since this compound was also labeled when the cultures were incubated with dl -[6- 14 C]α-aminoadipic acid, l -[3,3′- 3 H]cystine, or dl -[1- 14 C]valine, its identity with the synthetic lld -tripeptide can be accepted. No δ-( l -α-aminoadipyl)- l -cysteine or lll -tripeptide were detected. The implications of these findings for tripeptide and penicillin biosynthesis are discussed.

Genetic and Biochemical Studies of Mutants of Penicillium chrysogenum Impaired in Penicillin Production

“…Its similarity to isopenicillin N and thus to penicillin was recognized when the former was identified by Flynn et al (1962) and Cole & Batchelor (1963). The tripeptide has the same optical configuration in Acremonium chrysogenum and P. chrysogenum (Loder & Abraham, 1971 ;Adriaens et al, 1975). However, the latter authors suggested the possibility that an 'all L' tripeptide is the precursor of penicillin and of the 'LLD' tripeptide, both of which were excreted.…”

“…chrysogenum lacking the ability to produce detectable amounts of cephalosporin C -those with, and those without the ability to synthesize the sulphur-containing peptides (including the tripeptide) described by Loder & Abraham (1971). Adriaens et al (1975) found LLD tripeptide in a penicillin-producing and in a non-producing strain of P. chrysogenum. Our discovery that mutants from two complementation groups producing tripeptide were incapable of yielding significant amounts of antibiotic directed our attention to the final steps in the pathway.…”

Naturally Occurring β-Lactams

“…Later, the tripeptide from P. chrysogenum was also shown to have the LLD stereochemistry by CHAN et al (242) ADRIENS et al (243) also concluded that the P. chrysogenum tripeptide possesses the LLD stereochemistry by passing the tripeptide through an amino acid analyser which could distinguish between the synthetic LLD and LLL-tripeptides. They could find no evidence of the LLL-tripeptide in P. chrysogenum.…”

“…Wild-fire toxin is an unstable substance rapidly converted at neutral pH to isotabtoxin (242) by way of intramolecular attack of the amino-group on the ~-lactam. Hydrolysis of wildfire toxin gives threonine and tabtoxinine (243). In the course of a screening programme which produced a number of antimetabolites from various microorganisms, SCANNELL has described the isolation of a monocyclic ~-lactam from an unidentified Streptomyces species (3).…”

Natural Beta-Lactam Antibiotics

“…The tri peptide was shown to be of LLD-confi guration (9,26,39,87). In the cell-free system of Cephalosporium acremonium (87), a small amount of radioac tivity from [14C]valine was found to be incorporated in Penicillin N (17,37).…”