Department of Chemical Engineering, Konkuk University, Seoul 143-701, Republic of Korea.
Bioorg Med Chem Lett. 2012 Mar 1;22(5):1931-5. doi: 10.1016/j.bmcl.2012.01.049. Epub 2012 Jan 26.
A nicotinamide adenine dinucleotide (NADH) oxidase from Streptococcus pyogenes MGAS10394 (SpNox) was cloned and overexpressed in Escherichia coli BL21 (DE3). The purified SpNox enzyme had optimal pH and temperature of 7.0 and 55°C, respectively, with a K(m) of 27.0μM and a k(cat)/K(m) of 1.1×10(7)s(-1)M(-1). SpNox showed the highest activity among all known NADH oxidases, and site-directed mutagenesis and docking analysis shed light on the molecular basis of its unusually high activity. The characteristics of SpNox may prove to be useful for NAD(+) regeneration in the production of l-rare sugar.
一株酿脓链球菌 MGAS10394（SpNox）来源的烟酰胺腺嘌呤二核苷酸（NADH）氧化酶在大肠杆菌 BL21（DE3）中被克隆和过表达。纯化后的 SpNox 酶最适 pH 和温度分别为 7.0 和 55°C，K(m)为 27.0μM，k(cat)/K(m)为 1.1×10(7)s(-1)M(-1)。SpNox 在所有已知的 NADH 氧化酶中表现出最高的活性，定点突变和对接分析揭示了其异常高活性的分子基础。SpNox 的特性可能有助于 l-稀有糖生产中 NAD(+)的再生。
