Bacillaene, a novel polyene antibiotic, was discovered and isolated from fermentation broths of a strain of Bacillus subtilis. The novel antibiotic has a nominal molecular weight of 580 and an empirical formula of C3 5H48O7.Bacillaene is active against a broad spectrum of bacteria in agar-plate diffusion assays. Studies in vitro indicate that the antibiotic inhibits prokaryotic protein synthesis but not eukaryotic protein synthesis. Cell survival studies performed with strains of Escherichia coli indicate that the antibiotic is a bacteriostatic agent.

The biosynthesis of monobactams by strains of Chromobacterium violaceum, Acetobacter sp., and Agrobacterium radiobacter was studied. Monobactams were produced during logarithmic growth by C. violaceum and Acetobacter sp. and during late log growth on glycerol and in the stationary phase by A. radiobacter. The addition of various amino acids failed to significantly stimulate monobactam production in any of the producing organisms. Several 14C-amino acids and pyruvate were incorporated in vivo into monobactams. Serine, glycine, and cysteine were better incorporated than alanine or aspartate, whereas an excess of nonradioactive serine depressed the incorporation of labeled cysteine,

Plastatin and the known fungal metabolite, luteosporin, have been isolated from fermentations of Penicillium chermesinum as inhibitors of porcine pancreatic phospholipase A2 (PLA2). Structure 1 for plastatin was deduced from its spectroscopic properties. Plastatin and luteosporin inhibited pancreatic PLA.2 competitively with Ki values of 0.89 uM and 12.8 ,1M, respectively. PLA2 preparations from Naja naja and Crotalus adainanteus were not significantly inhibited by plastatin and luteosporin.

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A screen for antibiotics with activity against tetracycline-resistant microorganisms has led to the isolation of Dactylosporangium sp. (ATCC53693), a producer of several novel tetracycline derivatives. The major fermentation products, dactylocyclines A and B, were purified and MIC values determined against tetracycline-resistant and tetracycline-sensitive Gram-positive bacteria. The dactylocyclines represent the first naturally occuring tetracycline C2 amides which lack cross resistance with tetracycline.