Institutes of Physical Science and Information Technology, Anhui University, Hefei, 230601, Anhui, China; School of Life Sciences, Anhui University, Hefei, 230601, Anhui, China.
Institutes of Physical Science and Information Technology, Anhui University, Hefei, 230601, Anhui, China; School of Life Sciences, Anhui University, Hefei, 230601, Anhui, China; Key Laboratory of Human Microenvironment and Precision Medicine of Anhui Higher Education Institutes, Anhui University, Hefei, 230601, Anhui, China.
Biochem Biophys Res Commun. 2024 Nov 19;734:150767. doi: 10.1016/j.bbrc.2024.150767. Epub 2024 Sep 29.
Vitamin B is involved in many important biochemical reactions for humans, and its deficiency can lead to serious diseases. The industrial production of vitamin B is achieved through microbial fermentation. In this work, we determine the crystal structures of the l-threonine-O-3-phosphate (Thr-P) decarboxylase CobC from Sinorhizobium meliloti (SmCobC), an industrial vitamin B-producing bacterium, in apo form and in complex with a reaction intermediate. Our structures supported the Thr-P decarboxylase activity of SmCobC and revealed that the positively charged substrate-binding pocket between the large and small domains determines its substrate selectivity for Thr-P. Moreover, our results provided evidence for the proposition that the AP-P linker is formed by direct incorporation of AP-P in the biosynthetic pathway of vitamin B in S.meliloti.
维生素 B 参与人体许多重要的生化反应，其缺乏可导致严重疾病。维生素 B 的工业生产是通过微生物发酵实现的。在这项工作中，我们确定了产维生素 B 的工业细菌苜蓿中华根瘤菌（Sinorhizobium meliloti）中 l-苏氨酸-O-3-磷酸（Thr-P）脱羧酶 CobC 的晶体结构，分别为apo 形式和与反应中间体结合的形式。我们的结构支持 SmCobC 的 Thr-P 脱羧酶活性，并揭示了大小结构域之间带正电荷的底物结合口袋决定其对 Thr-P 的底物选择性。此外，我们的结果为 AP-P 连接物是通过直接将 AP-P 掺入苜蓿中华根瘤菌中维生素 B 生物合成途径的观点提供了证据。
