Newton G L, Arnold K, Price M S, Sherrill C, Delcardayre S B, Aharonowitz Y, Cohen G, Davies J, Fahey R C, Davis C
Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla , California 92093, USA.
J Bacteriol. 1996 Apr;178(7):1990-5. doi: 10.1128/jb.178.7.1990-1995.1996.
Mycothiol [2-(N-acetylcysteinyl)amido-2-deoxy-alpha-D-glucopyranosyl- (1-->1)-myo-inositol] (MSH) has recently been identified as a major thiol in a number of actinomycetes (S. Sakuda, Z.-Y. Zhou, and Y. Yamada, Biosci. Biotech. Biochem. 58:1347-1348, 1994; H. S. C. Spies and D. J. Steenkamp, Eur. J. Biochem. 224:203-213, 1994; and G. L. Newton, C. A. Bewley, T. J. Dwyer, R. Horn, Y. Aharonowitz, G. Cohen, J. Davies, D. J. Faulkner, and R. C. Fahey, Eur. J. Biochem. 230:821-825, 1995). Since this novel thiol is more resistant than glutathione to heavy-metal ion-catalyzed oxidation, it seems likely to be the antioxidant thiol used by aerobic gram-positive bacteria that do not produce glutathione (GSH). In the present study we sought to define the spectrum of organisms that produce MSH. GSH was absent in all actinomycetes and some of the other gram-positive bacteria studied. Surprisingly, the streptococci and enterococci contained GSH, and some strains appeared to synthesize it rather than import it from the growth medium. MSH was found at significant levels in most actinomycetes examined. Among the actinobacteria four Micrococcus species produced MSH, but MSH was not found in representatives of the Arthrobacter, Agromyces, or Actinomyces genera. Of the nocardioforms examined, Nocardia, Rhodococcus, and Mycobacteria spp. all produced MSH. In addition to the established production of MSH by streptomycetes, we found that Micromonospora, Actinomadura, and Nocardiopsis spp. also synthesized MSH. Mycothiol production was not detected in Propionibacterium acnes or in representative species of the Listeria, Staphylococcus, Streptococcus, Enterococcus, Bacillus, and Clostridium genera. Examination of representatives of the cyanobacteria, purple bacteria, and spirochetes also gave negative results, as did tests of rat liver, bonito, Candida albicans, Neurospora crassa, and spinach leaves. The results, which indicate that MSH production is restricted to the actinomycetes, could have significant implications for the detection and treatment of infections with actinomycetes, especially those caused by mycobacteria.
麦角硫因2-(N-乙酰半胱氨酰)氨基-2-脱氧-α-D-吡喃葡萄糖基-(1→1)-肌醇最近被确定为多种放线菌中的主要硫醇（佐久田诚、周ZY和山田洋，《生物科学、生物技术与生物化学》58:1347 - 1348，1994；H.S.C.斯皮斯和D.J.斯廷坎普，《欧洲生物化学杂志》224:203 - 213，1994；以及G.L.牛顿、C.A. Bewley、T.J.德怀尔、R.霍恩、Y.阿哈罗诺维茨、G.科恩、J.戴维斯、D.J.福克纳和R.C.费伊，《欧洲生物化学杂志》230:821 - 825，1995）。由于这种新型硫醇比谷胱甘肽对重金属离子催化的氧化更具抗性，它似乎可能是不产生谷胱甘肽(GSH)的需氧革兰氏阳性细菌所使用的抗氧化硫醇。在本研究中，我们试图确定产生MSH的生物体范围。在所研究的所有放线菌和一些其他革兰氏阳性细菌中均不存在GSH。令人惊讶的是，链球菌和肠球菌含有GSH，并且一些菌株似乎是合成而非从生长培养基中摄取GSH。在大多数检测的放线菌中发现了显著水平的MSH。在放线杆菌中，四种微球菌属物种产生MSH，但在节杆菌属、土壤杆菌属或放线菌属的代表物种中未发现MSH。在所检测的诺卡氏菌型中，诺卡氏菌属、红球菌属和分枝杆菌属均产生MSH。除了已确定链霉菌能产生MSH外，我们还发现小单孢菌属、马杜拉放线菌属和拟诺卡氏菌属也能合成MSH。在痤疮丙酸杆菌或李斯特菌属、葡萄球菌属、链球菌属、肠球菌属、芽孢杆菌属和梭菌属的代表物种中未检测到麦角硫因的产生。对蓝细菌、紫色细菌和螺旋体的代表物种的检测也得到了阴性结果，对大鼠肝脏、鲣鱼、白色念珠菌、粗糙脉孢菌和菠菜叶的检测结果也是如此。这些结果表明MSH的产生仅限于放线菌，这可能对放线菌感染尤其是分枝杆菌引起的感染的检测和治疗具有重要意义。
