Hefei National Laboratory for Physical Science at Microscale and School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027, China.
J Mol Biol. 2012 Jan 13;415(2):382-92. doi: 10.1016/j.jmb.2011.11.016. Epub 2011 Nov 15.
Rv0899 from Mycobacterium tuberculosis belongs to the OmpA (outer membrane protein A) family of outer membrane proteins. It functions as a pore-forming protein; the deletion of this gene impairs the uptake of some water-soluble substances, such as serine, glucose, and glycerol. Rv0899 has also been shown to play a part in low-pH environment adaption, which may play a part in pathogenic mycobacteria overcoming the host's defense mechanisms. Based on many bacterial physiological data and recent structural studies, it was proposed that Rv0899 forms an oligomeric channel to carry out such functions. In this work, biochemical and structural data obtained from solution NMR and EPR spectroscopy indicated that Rv0899 is a monomeric membrane-anchoring protein with two separate domains, rather than an oligomeric pore. Using NMR chemical shift perturbation and isothermal calorimetric titration assays, we show that Rv0899 was able to interact with Zn(2+) ions, which may indicate a role for Rv0899 in the process of Zn(2+) acquisition.
结核分枝杆菌的 Rv0899 属于外膜蛋白 A（OmpA）家族的外膜蛋白。它作为孔形成蛋白发挥作用；该基因的缺失会损害一些水溶性物质（如丝氨酸、葡萄糖和甘油）的摄取。Rv0899 还被证明在低 pH 值环境适应中发挥作用，这可能有助于致病性分枝杆菌克服宿主的防御机制。基于许多细菌生理数据和最近的结构研究，提出 Rv0899 形成一个寡聚体通道来执行这些功能。在这项工作中，从溶液 NMR 和 EPR 光谱获得的生化和结构数据表明，Rv0899 是一种具有两个独立结构域的单体膜锚定蛋白，而不是寡聚体孔。通过 NMR 化学位移扰动和等温热滴定实验，我们表明 Rv0899 能够与 Zn（2+）离子相互作用，这可能表明 Rv0899 在 Zn（2+）获取过程中发挥作用。
