Van Lanen Steven G, Lin Shuangjun, Horsman Geoff P, Shen Ben
Division of Pharmaceutical Sciences, University of Wisconsin-Madison, 777 Highland Avemue, Madison, WI 53705, USA.
FEMS Microbiol Lett. 2009 Nov;300(2):237-41. doi: 10.1111/j.1574-6968.2009.01802.x. Epub 2009 Sep 27.
The C-1027 enediyne antitumor antibiotic from Streptomyces globisporus possesses an (S)-3-chloro-5-hydroxy-beta-tyrosine moiety, the chloro- and hydroxy-substituents of which are installed by a flavin-dependent halogenase SgcC3 and monooxygenase SgcC, respectively. Interestingly, a single flavin reductase, SgcE6, can provide reduced flavin to both enzymes. Bioinformatics analysis reveals that, similar to other flavin reductases involved in natural product biosynthesis, SgcE6 belongs to the HpaC-like subfamily of the Class I flavin reductases. The present study describes the steady-state kinetic characterization of SgcE6 as a strictly NADH- and FAD-specific enzyme.
来自球形链霉菌的烯二炔类抗肿瘤抗生素C-1027含有一个（S）-3-氯-5-羟基-β-酪氨酸部分，其氯取代基和羟基取代基分别由黄素依赖性卤化酶SgcC3和单加氧酶SgcC安装。有趣的是，单一的黄素还原酶SgcE6可以为这两种酶提供还原型黄素。生物信息学分析表明，与参与天然产物生物合成的其他黄素还原酶类似，SgcE6属于I类黄素还原酶的HpaC样亚家族。本研究描述了SgcE6作为一种严格的NADH和FAD特异性酶的稳态动力学特征。
