Dorrigocins: novel antifungal antibiotics that change the morphology of ras-transformed NIH/3T3 cells to that of normal cells. I. Taxonomy of the producing organism, fermentation and biological activity.

The dorrigocins are new secondary metabolites produced by submerged fermentation of a streptomycete which was isolated from a soil sample collected in Australia. The dorrigocins show moderate antifungal activity and reverse the morphology of ras-transformed NIH/3T3 cells from a transformed phenotype to a normal one. The producing culture was identified as Streptomyces platensis subsp. rosaceus strain AB1981F-75.

Aselacins, novel compounds that inhibit binding of endothelin to its receptor. I. The producing organism, fermentation and biological activity.

A radioligand test to detect inhibitors of endothelin-1 binding to its receptors in bovine atrial and porcine cerebral membranes was used to screen fungal metabolites from stationary fermentations. Inhibitory activity, observed in culture extracts of two Acremonium species, led to the discovery of aselacins A, B and C. Aselacin A inhibits binding to both membrane fractions with IC50s of approximately 20 micrograms/ml.

5-N-acetylardeemin, a novel heterocyclic compound which reverses multiple drug resistance in tumor cells. I. Taxonomy and fermentation of the producing organism and biological activity.

The ardeemins are a new family of secondary metabolites produced by submerged fermentation of a fungus which was isolated from a soil sample collected in Brazil. Based on taxonomic studies, the producing culture was identified as Aspergillus fischeri var. brasiliensis strain AB 1826M-35. 5-N-Acetylardeemin potentiated the cytotoxicity of the anticancer agent vinblastine in multidrug resistant human tumor cells.

Calbistrins, novel antifungal agents produced by Penicillium restrictum. I. Production, taxonomy of the producing organism and biological activity.

A novel antibiotic complex, named the calbistrins, has been discovered in the culture broth of a soil fungus. The producing organism, designated AB 1875C-28, was identified as a strain of Penicillium restrictum. Calbistrin A, the most potent of the 4-membered complex, has MICs of 0.78 micrograms/ml against Candida albicans. Only poor activity is observed against non-candida yeasts, filamentous fungi and bacteria.

Dunaimycins, a new complex of spiroketal 24-membered macrolides with immunosuppressive activity. I. Taxonomy of the producing organisms, fermentation and antimicrobial activity.

The dunaimycins are a new complex of spiroketal 24-membered macrolides discovered in the fermentation broth of two actinomycetes. Based on taxonomic studies these two cultures, which were isolated from soil, were identified as Streptomyces diastatochromogenes strains AB 1691Q-321 and AB 1711J-452. The dunaimycins possess both immunosuppressive and antimicrobial activity.

Coumamidines, new broad spectrum antibiotics of the cinodine type. I. Discovery, taxonomy of the producing organism and fermentation.

Coumamidines are water-soluble basic antibiotics related to the glycocinnamoylspermidines. They are produced by a soil isolate designated Saccharopolyspora sp. AB 1167L-65. The coumamidines have broad spectrum activity and were selected in a screen for substances which inhibit Pseudomonas aeruginosa.

Phenelfamycins, a novel complex of elfamycin-type antibiotics. I. Discovery, taxonomy and fermentation.

Phenelfamycins A, B, C, E, F and unphenelfamycin have been discovered in the fermentation broth of two soil isolates, designated AB 999F-80 and AB 1047T-33. These isolates were identified as strains of Streptomyces violaceoniger. The antibiotics were selected for their activity against anaerobic bacteria.

Coloradocin, an antibiotic from a new Actinoplanes. I. Taxonomy, fermentation and biological properties.

Coloradocin was discovered in a screen for anti-anaerobe activity. The producing organism was determined to be a new species of Actinoplanes, designated Actinoplanes coloradoensis sp. nov. Coloradocin inhibits Bacteroides, Clostridium and other anaerobes. It does not inhibit most aerobic bacteria but is effective against Neisseria gonorrhoeae and Haemophilus influenzae. Coloradocin has low acute toxicity.

Benzanthrins A and B, a new class of quinone antibiotics. I. Discovery, fermentation and antibacterial activity.

Nocardia lurida has been shown to produce two novel quinone antibiotics, benzanthrins A and B. The antibiotics were discovered in concentrated butanol extracts of fermentation broths and were separated by TLC and HPLC. Benzanthrins A and B were produced in a fermentation medium consisting of glucose, yeast, selected peptones and CaCO3. The antibiotics were present primarily at 66 hours in shake flask fermentations and from 66 to 162 hours in 14-liter fermentors. Benzanthrins A and B inhibited a number of Gram-positive pathogenic bacteria but were inactive against Gram-negative bacteria.