Structure and Mechanism of ORF36, an Amino Sugar Oxidizing Enzyme in Everninomicin Biosynthesis,
作者:Jessica L. Vey、Ahmad Al-Mestarihi、Yunfeng Hu、Michael A. Funk、Brian O. Bachmann、T. M. Iverson
DOI:10.1021/bi101336u
日期:2010.11.2
products and identifies an off-pathway product that correlates with the oxidation product of a progenitor substrate. The 3.15 Å resolution X-ray crystal structure of ORF36 reveals a tetrameric enzyme that shares a fold with acyl-CoA dehydrogenases and class D flavin-containing monooxygenases, including the nitrososynthase KijD3. However, ORF36 and KijD3 have unusually open active sites in comparison to these
Everninomicin 是一种高度修饰的八糖,属于抗生素正霉素家族,具有强效的革兰氏阳性抗生素活性,包括对多重耐药肠球菌和金黄色葡萄球菌的广谱功效。其独特的结构特征之一是硝基糖,即l- evernitrose,它的类似物装饰了各种天然产品。最近,我们从Micromonospora carbonacea var. 中鉴定了一种由orf36编码的亚硝基合酶。AFRICANA介导合成产生的胸苷二磷酸(TDP)的依赖黄素的双氧化-升-外延-vancosamine 到相应的亚硝基糖。在此,我们利用五酶体外途径来验证 ORF36 催化生物源性TDP - 1 - epi- vancosamine 的氧化,并确定 ORF36 是否对其任何生物合成祖细胞表现出催化能力,这些祖细胞是体内亚硝基合酶的候选底物. 祖细胞仅经历单氧化反应并终止于羟胺氧化态。在18 O 2存在下进行体外反应确定分子氧,而不是来自水中的氧,被结合到