production of oxytetracycline by an isolated strain of streptomyces rimosus from iranian soil was investigated using a special fermentation medium. a comparative study was performed with standard strain ptcc 1144 using the following parameters optimum growth conditions with respect to time, ph, and different amounts of corn steep liquor. surprisingly, the production yield of the wild strain was...

Combining the high specificity of bacterial biosensors and the resolution power of fluorescence-activated cell sorting (FACS) provided qualitative detection of oxytetracycline production by Streptomyces rimosus in soil microcosms. A plasmid containing a transcriptional fusion between the tetR-regulated P(tet) promoter from Tn10 and a FACS-optimized gfp gene was constructed. When harbored by Esc...

Oxytetracycline: source and mechanisms of resistance. Oxytetracycline (Terramycin) is a naturally produced tetracycline antibiotic of Streptomyces rimosus, with a spectrum of activity similar to chlortetracycline and tetracycline and remarkable thermostability (16). In plant agriculture, oxytetracycline is used in the USA primarily on pear and apple for fire blight management. Oxytetracycline i...

A restriction map of the 8 Mb linear chromosome of Streptomyces rimosus R6-501 was constructed for the enzymes Asel (13 fragments) and Dral (7 fragments). Linking clones for all 12 Asel sites and 5 of the 6 Dral sites were isolated. The chromosome has terminal inverted repeats of 550 kb, which are the longest yet reported for a Streptomyces species. The oxytetracycline gene cluster lies about 6...

During 2 years, from March 1987 to April 1989, 600 samples of soil and plant were collected from different cities of northern provinces of Iran. Out of the six hundred samples 58 Actinomycetes, 9 Pseudallescheria boydii, 10 Sporothrix schenckii, and 4 Sporothrix schenckii-like fungi were isolated as the following: Streptomyces griseus from 31 samples (38.27%), Nocardia asteroides from 8 sa...

During 2 years, from March 1987 to April 1989 ,600 samples of soil and plant were collected from different cities of northern provinces of Iran. Out of the six hundred samples 58 Actinomycetes, 9 Pseudallescheria boydii, 10 Sporothrix schenckii, and 4 Sporothrix schenckii-like fungi were isolated as the following: Streptomyces griseus from 31 samples (38.27%), Nocardia asteroides from 8 samples...

Primaquine, an 8-amino-6-methoxyquinoline antimalarial agent, was subjected to metabolic studies with microorganisms. Streptomyces rimosus converted primaquine to the previously reported N-acetyl derivative. Continued incubation of S. rimosus resulted in the formation of a minor dimeric metabolite. The structure of the minor dimeric metabolite was proposed based primarily on its spectral data (...

The oxytetracycline-producing Streptomyces rimosus strains R6-65 and R7 (ATCC 10970) are lysogenic for the two narrow-host-range phages RP2 and RP3. Both phages are released at low frequency from the lysogenic strains and form plaques on 'cured' S. rimosus strains. RP2 and RP3 are of similar shape with flexible tails and contain double-stranded DNA of about 70% G+C with cohesive ends (group B1 ...