Structures of grixazone A and B, A-factor-dependent yellow pigments produced under phosphate depletion by Streptomyces griseus.

A-factor and phosphate depletion signals are transmitted to the grixazone biosynthesis genes via the pathway-specific transcriptional activator GriR.

Grixazone (GX), which is a diffusible yellow pigment containing a phenoxazinone chromophore, is one of the secondary metabolites under the control of A-factor (2-isocapryloyl-3R-hydroxymethyl-gamma-butyrolactone) in Streptomyces griseus. GX production is also induced by phosphate starvation. The whole biosynthesis gene cluster for GX was cloned and characterized. The gene cluster consisting of ...

Oxidation of Meloxicam by Streptomyces griseus

The aim of the present investigation was to biotransform the anti-inflammatory compound meloxicam by enzymes present in whole cells of five actinomycete cultures to produce novel bioactive derivatives. Among the actinomycetes screened, Streptomyces griseus NCIM 2622 was found to possess the enzyme system(s) that oxidize meloxicam into two metabolites whereas that present in S. griseus NCIM 2623...

Sequential expression of macromolecule biosynthesis and candicidin formation in Streptomyces griseus.

Streptomyces griseus did not produce the polyene macrolide antibiotic candicidin during the initial growth phase characterized by rapid RNA synthesis. the absence of candicidin production when RNA or protein synthesis was inhibited by rifampicin or chloramphenicol suggests a transcriptionally controlled late formation of the candicidin synthases. Phosphate levels in the medium control the rate ...

A sigmaB-like factor responsible for carotenoid biosynthesis in Streptomyces griseus.

Self-cloning experiments with a high-copy-number plasmid and Streptomyces griseus IFO13350 led to the cloning of a 11-kb DNA fragment that conferred yellow pigment production on the host. The cloned fragment contained a gene cluster for carotenoid biosynthesis, in which two polycistrons, crtE (encoding geranylgeranyl pyrophosphate synthase)-crtI (phytoene dehydrogenase)-crtB (phytoene synthase)...

Isolation and characterization of a phage active against streptomyces griseus