Studies of the Peptide Antibiotic Suzukacillin

Suzukacillin produced by Trichoderma viride 63Cl strain was purified and shown to be separated into two components A and B on thin-layer chromatography. The component A was isolated and crystallized from the mixture of components by alumina column chromatography. The component A is composed of six amino acids, Gly, Glu, Ala, Pro, Val, Leu and an unknown amino acid. This unknown amino acid was identified as α-amino isobutyric acid. It is supposed that α-amino isobutyric acid is biosynthesized mainly from l-valine by the isotopic experiments. Suzukacillin formation by Trichoderma viride 63Cl was stimulated by the addition of l-Asn, GABA, l-Ser, Gly and l-Arg into the medium.