Biosynthesis of extracellular guanyl-specific ribonuclease by Bacillus circulans

Biosynthesis of extracellular alkaline guanyl-specific RNase by Bacillus circulans (RNase Bci) was studied. Synthesis of the enzyme by the culture started in the late exponential phase and was inhibited by inorganic phosphate and glucose, in contrast to the biosynthesis of its structural and functional homologue, RNase Ba (barnase) of B. amyloliquefaciens. It is suggested that differences in the regulation of the biosynthesis of RNases Bci and Ba are related to different structures of their gene promoters. © 1998 MAHK Hayka/Interperiodica Publishing.