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 seco...

Scanning electron microscopy was used to follow fruiting body formation by pure cultures of Chondromyces crocatus M38 and Stigmatella aurantica. Vegetative cells were grown on SP agar and then transferred to Bonner salts agar for fructification. Fruiting in both species commences with the formation of aggregation centers which resemble a fried egg in appearance. In Chondromyces the elevated cen...

Stigmatella aurantiaca displays a complex developmental life cycle in response to starvation conditions that results in the formation of tree-like fruiting bodies capable of producing spores. The phage Mx8, first isolated from the close relative Myxococcus xanthus, is unable to infect S. aurantiaca cells and integrate into the genome. However, plasmids containing Mx8 fragments encoding the inte...

Tubulysins are a group of secondary metabolites produced by myxobacteria that inhibit the function eukayotic cytoskeleton. We developed pair PCR primers specifically amplified tubulysin biosynthetic genes. Using these primers, eight out eighty-one strains belonging to Cystobacteraceae family harbored putative genes were screened through analysis. The selected included two Archangium gephyra, St...

this work was to isolate and identify the bioactive secondary metabolite which was produced by myxobacterium stigmatella eracta wxnxj-b, and to evaluate its antitumor and apoptosis-inducing effects. the results showed that one novel compound (molecular formula c29h25no3) was isolated, purified by sephadex lh-20 column chromatography and preparative rp-hplc, and identified as 5-(6-benzyl-quinoli...

A third group o f antibiotics, the aurachins, have been isolated from the m yxobacterium Stigmatella aurantiaca. The aurachins chemically are quinolones, and four o f them (aurachins A D ) have been tested for their inhibitory activity in photosystem II and cytochrom e b/ccomplexes. A urachin C is the best inhibitor in photosystem II (p /50-value 7.2); its biochemical behaviour being the same l...

Alternative sigma factors have been detected in the myxobacterium Stigmatella aurantiaca during indole-induced sporulation, fruiting body formation and heat shock using an antiserum raised against sigma factor SigB. The time course of sigB gene expression was analysed by RT-PCR and by determining beta-galactosidase activity during development in a merodiploid strain that harboured a sigB-lacZ f...