Sun Xuesong, Ge Ruiguang, Chiu Jen-Fu, Sun Hongzhe, He Qing-Yu
Department of Chemistry, The University of Hong Kong, Pokfulam, Hong Kong, People's Republic of China.
FEBS Lett. 2008 Apr 16;582(9):1351-4. doi: 10.1016/j.febslet.2008.03.020. Epub 2008 Mar 24.
Lipoprotein MtsA is a critical component of MtsABC responsible for iron binding and transport in the Gram-positive bacterium Streptococcus pyogenes. The present collective experimental data establish that Fe(2+) is the primary binding ion for MtsA under optimal physiologically relevant conditions. The binding affinities of MtsA to metal ions are Fe(2+)>Fe(3+)>Cu(2+)>Mn(2+)>Zn(2+). We report for the first time that bicarbonate is required as a synergistic anion for stable ferrous binding to MtsA, similar to the iron binding in human transferrin. This work provides valuable information, which helps to understand iron metabolism in bacteria, and creates a basis for developing strategies to suppress bacterial infection.
脂蛋白MtsA是酿脓链球菌中负责铁结合和运输的MtsABC的关键组成部分。目前的综合实验数据表明，在最佳生理相关条件下，Fe(2+)是MtsA的主要结合离子。MtsA对金属离子的结合亲和力为Fe(2+)>Fe(3+)>Cu(2+)>Mn(2+)>Zn(2+)。我们首次报道，碳酸氢盐作为一种协同阴离子是亚铁与MtsA稳定结合所必需的，这类似于人转铁蛋白中的铁结合。这项工作提供了有价值的信息，有助于理解细菌中的铁代谢，并为制定抑制细菌感染的策略奠定了基础。
