Actinobacterial Acyl Coenzyme A Synthetases Involved in Steroid Side-Chain Catabolism
作者:Israël Casabon、Kendra Swain、Adam M. Crowe、Lindsay D. Eltis、William W. Mohn
DOI:10.1128/jb.01012-13
日期:2014.2
activate the C8 side chain of cholesterol. Both CasGRHA1 and FadD17Mtb are steroid-24-oyl-CoA synthetases. CasG and its orthologs activate the C5 side chain of cholate, while FadD17 and its orthologs appear to activate the C5 side chain of one or more cholesterol metabolites. CasIRHA1 is a steroid-22-oyl-CoA synthetase, representing orthologs that activate metabolites with a C3 side chain, which accumulate
细菌类固醇分解代谢是全球碳循环的重要组成部分,在药物合成中有应用。这种分解代谢的途径涉及多种酰基辅酶 A (CoA) 合成酶,它们激活链烷酸酯取代基进行 β-氧化。这些合成酶的功能知之甚少。我们对来自约氏红球菌 RHA1 的胆酸盐分解代谢途径和结核分枝杆菌的胆固醇分解代谢途径的四种不同的酰基辅酶 A 合成酶进行了酶促表征。对预测参与类固醇代谢的 70 种酰基辅酶 A 合成酶进行的系统发育分析表明,所表征的合成酶各自代表在类固醇侧链降解中具有独特功能的直系同源类。合成酶对链烷酸酯取代基的长度具有特异性。FadD19 来自 M。结核分枝杆菌 H37Rv (FadD19Mtb) 转化 3-oxo-4-cholesten-26-oate (kcat/Km = 0.33 × 10(5) ± 0.03 × 10(5) M(-1) s(-1)) 并代表直向同源物激活胆固醇的 C8 侧链。CasGRHA1