Chemical modification experiments and kinetic measurements have been carried out to identify the active site components of guanylspecific ribonuclease Sa (E. C. 3.1.4.8.) from Streptomyces aureofaciens. Modification experiments with phenylglyoxal and diketene showed that neither arginine nor lysine residues, which could bind the negatively charged phosphate group of the substrate, belonged to t...

Glucose 6phosphate dehydrogenase from streptomyces aureofaciens was purified and inactivated by pyridoxal 5′-phosphate (PLP). The inactivation was a pseudo-first order and time-dependent reaction. Complete inactivation was achieved at 0.2mM PLP within 16 minutes. The type of inhibition was competitive with respect to Glucose 6phosphate. Spectral characteristics of PLP-enzyme complex corresponde...

Natural tetracycline (TC) antibiotics were the first major class of therapeutics to earn the distinction of 'broad-spectrum antibiotics' and they have been used since the 1940s against a wide range of both Gram-positive and Gram-negative pathogens, mycoplasmas, intracellular chlamydiae, rickettsiae and protozoan parasites. The second generation of semisynthetic tetracyclines, such as minocyclin...

Streptomycetes are soil microorganisms exposed to various stresses that activate specialized responses whose coordinated action promotes growth under adverse conditions. Ribosomes having a highly cooperative structure are potential target for control mechanisms that generate signal and activate adaptive regulons or developmental programs. We examined how Streptomyces aureofaciens producing tetr...