Department of Biology, Emory University, Atlanta, GA 30319, USA.
Future Microbiol. 2010 Mar;5(3):419-29. doi: 10.2217/fmb.10.14.
Streptomyces are Gram-positive, soil-dwelling bacteria that are prolific producers of antibiotics. Most of the antibiotics used in clinical and veterinary medicine worldwide are produced as natural products by members of the genus Streptomyces. The regulation of antibiotic production in Streptomyces is complex and there is a hierarchy of regulatory systems that extends from the level of individual biosynthetic pathways to global regulators that, at least in some streptomycetes, control the production of all the antibiotics produced by that organism. Ribonuclease III, a double-strand specific endoribonuclease, appears to be a global regulator of antibiotic production in Streptomyces coelicolor, the model organism for the study of streptomycete biology. In this review, the enzymology of RNA degradation in Streptomyces is reviewed in comparison with what is known about the degradation pathways in Escherichia coli and other bacteria. The evidence supporting a role for RNase III as a global regulator of antibiotic production in S. coelicolor is reviewed and possible mechanisms by which this regulation is accomplished are considered.
链霉菌是革兰氏阳性、土壤栖息的细菌，是抗生素的丰富生产者。全世界用于临床和兽医医学的大多数抗生素都是由链霉菌属的成员作为天然产物生产的。链霉菌中抗生素的产生是复杂的，存在一个从单个生物合成途径到全局调节剂的层次结构，至少在一些链霉菌中，全局调节剂控制该生物体产生的所有抗生素的产生。核糖核酸酶 III 是一种双链特异性内切核糖核酸酶，似乎是链霉菌色氨酸生产抗生素的全局调节剂，是研究链霉菌生物学的模式生物。在这篇综述中，比较了链霉菌中 RNA 降解的酶学与大肠杆菌和其他细菌中已知的降解途径。综述了核糖核酸酶 III 作为链霉菌色氨酸抗生素生产全局调节剂的作用证据，并考虑了完成这种调节的可能机制。
