Kumar Anurag, Li Jinglin, Kondaveeti Sanath, Singh Bakul, Shanmugam Ramasamy, Kalia Vipin Chandra, Kim In-Won, Lee Jung-Kul
Division of Chemical Engineering, Konkuk University, Seoul, South Korea.
Front Bioeng Biotechnol. 2022 Sep 12;10:1001726. doi: 10.3389/fbioe.2022.1001726. eCollection 2022.
An NAD-dependent xylitol dehydrogenase from (AfXDH) was cloned and successfully expressed in . AfXDH gene sequence revealed an open reading frame of 1,110 bp, encoding a polypeptide of 369 amino acids with a calculated molecular mass of 38,893 Da. Among various polyols, sorbitol and xylitol were preferred substrates of AfXDH with K values of 16.2 and 16.9 mM, respectively. AfXDH showed the highest activity in Tris-glycine-NaOH buffer (pH 9.5) at 50°C; it required Zn or Mn for enzyme activity. The half-life at 40°C and half denaturation temperature (T) was 200 min and 45°C, respectively. Bioinformatic analyses along with biochemical properties confirmed that AfXDH belonged to the medium-chain dehydrogenase/reductase family. AfXDH exhibits higher thermostability and values than those of other XDHs. The feasibility of using AfXDH in l-xylulose production was demonstrated. AfXDH, when coupled with NADH oxidase, efficiently converted xylitol to l-xylulose with 97% yield, suggesting its usefulness for the industrial l-xylulose production from xylitol.
从[具体来源]克隆得到一种依赖NAD的木糖醇脱氢酶（AfXDH），并在[具体宿主]中成功表达。AfXDH基因序列显示一个1110 bp的开放阅读框，编码一个369个氨基酸的多肽，计算分子量为38,893 Da。在各种多元醇中，山梨醇和木糖醇是AfXDH的优选底物，其K值分别为16.2和16.9 mM。AfXDH在50°C的Tris-甘氨酸-NaOH缓冲液（pH 9.5）中显示出最高活性；其酶活性需要Zn或Mn。在40°C时的半衰期和半变性温度（T）分别为200分钟和45°C。生物信息学分析以及生化特性证实AfXDH属于中链脱氢酶/还原酶家族。AfXDH比其他木糖醇脱氢酶表现出更高的热稳定性和[此处原文似乎有缺失信息]值。证明了使用AfXDH生产L-木酮糖的可行性。当与NADH氧化酶偶联时，AfXDH能以97%的产率将木糖醇高效转化为L-木酮糖，表明其在从木糖醇工业生产L-木酮糖方面的实用性。
