Department of Chemistry, University of Kentucky, Lexington, KY 40506-0055, USA.
FEBS Lett. 2012 Mar 9;586(5):585-95. doi: 10.1016/j.febslet.2011.10.048. Epub 2011 Nov 10.
Superoxide dismutases (SODs) catalyze the de toxification of superoxide. SODs therefore acquired great importance as O(2) became prevalent following the evolution of oxygenic photosynthesis. Thus the three forms of SOD provide intriguing insights into the evolution of the organisms and organelles that carry them today. Although ancient organisms employed Fe-dependent SODs, oxidation of the environment made Fe less bio-available, and more dangerous. Indeed, modern lineages make greater use of homologous Mn-dependent SODs. Our studies on the Fe-substituted MnSOD of Escherichia coli, as well as redox tuning in the FeSOD of E. coli shed light on how evolution accommodated differences between Fe and Mn that would affect SOD performance, in SOD proteins whose activity is specific to one or other metal ion.
超氧化物歧化酶（SODs）催化超氧化物的解毒。因此，随着产氧光合作用的进化，O2 变得普遍，SODs 变得非常重要。因此，这三种形式的 SOD 为我们提供了关于携带它们的生物体和细胞器的进化的有趣见解。尽管古老的生物体使用依赖 Fe 的 SOD，但环境的氧化作用使 Fe 的生物利用度降低，而且更危险。事实上，现代谱系更倾向于使用同源的 Mn 依赖的 SOD。我们对大肠杆菌中 Fe 取代的 MnSOD 的研究，以及大肠杆菌中 FeSOD 的氧化还原调谐，揭示了进化是如何适应会影响 SOD 性能的 Fe 和 Mn 之间的差异的，这些差异会影响 SOD 蛋白的活性，使其对一种或另一种金属离子具有特异性。
