The aurachins, new quinoline antibiotics from myxobacteria: production, physico-chemical and biological properties

The aurachins, new quinoline alkaloids, were extracted with acetone from the biomass of the myxobacterium, Stigmatella aurantiaca strain Sg a15 and purified by column chromatography. The four described aurachins A, B, C and D, were inhibitory for Gram-positive bacteria and a few yeasts and molds. They blocked NADH oxidation in beef heart submitochondrial particles.

Production, isolation, physico-chemical and biological properties of angiolam A, a new antibiotic from Angiococcus disciformis (Myxobacterales)

Angiolam A, a new lactone-lactam antibiotic, was isolated from the culture broth of the myxobacterium Angiococcus disciformis strain An d30. It was active against a few Gram-positive bacteria and mutant strains of Escherichia coli with increased permeability. It appears to interfere with protein synthesis.

Stigmatellin, a new antibiotic from Stigmatella aurantiaca (Myxobacterales). I. Production, physico-chemical and biological properties

An antibiotic activity was extracted from the cell mass of the myxobacterium, Stigmatella aurantiaca strain Sg a15. The antibiotic was toxic for yeasts and filamentous fungi, but not for most bacteria. The compound had the molecular formula C30H42O7, appears to be a new antibiotic, and was named stigmatellin. In addition to stigmatellin, the strain produced relatively large quantities of a second, structurally unrelated antibiotic, a mixture of three myxalamid homologues.

The myxalamids, new antibiotics from Myxococcus xanthus (Myxobacterales). I. Production, physico-chemical and biological properties, and mechanism of action

From the cell mass and culture supernatant of Myxococcus xanthus strain Mx X12 an antibiotic activity against yeasts, molds and some Gram-positive bacteria could be extracted. It consisted of 4 biologically active compounds which were named myxalamid A, B, C and D. The main component, myxalamid B, was shown to block in beef heart submitochondrial particles the respiratory chain at the site of complex I, i.e. NADH: ubiquinone oxidoreductase. The myxalamids are new antibiotics.