Archibald F
Crit Rev Microbiol. 1986;13(1):63-109. doi: 10.3109/10408418609108735.
The transition metal manganese is considered to be a minor micronutrient in both pro- and eukaryotes, usually being required from the environment at subnanomolar levels. Until recently, Mn was only known to function in cells as a cofactor for a few enzymatic reactions. A notable exception has been reported in many lactic acid bacterial species which require micromolar medium Mn levels for growth and contain up to 35 mM Mn. These high Mn concentrations are accompanied by the near or complete absence of intracellular iron and superoxide dismutase (SOD). Lacking hemes, Lactobacillus plantarum and related species contain a unique Mn-cofactored catalase as well as millimolar Mn(II) in a nonenzymic complex performing the function of the micromolar superoxide dismutase found in most other aerotolerant cells. The high Mn(II) levels are accumulated via an efficient active transport system and are stored intracellularly in a high molecular weight complex. Study of Lactobacillus plantarum has provided an interesting example of the substitution of Mn for Fe in several of the biological roles of Fe, an alternative mechanism of aerotolerance, and a better understanding of the unique biochemistry of the lactic acid bacteria.
过渡金属锰在原核生物和真核生物中都被视为一种微量的微量元素，通常在环境中以亚纳摩尔水平被需求。直到最近，人们只知道锰在细胞中作为少数酶促反应的辅因子发挥作用。在许多乳酸菌物种中报告了一个显著的例外情况，这些乳酸菌生长需要微摩尔水平的培养基锰，并且细胞内锰含量高达35 mM。这些高浓度的锰伴随着细胞内铁和超氧化物歧化酶（SOD）几乎完全缺失。植物乳杆菌及相关物种缺乏血红素，它们含有一种独特的锰辅助过氧化氢酶，以及在一种非酶复合物中含有毫摩尔浓度的锰（II），该复合物发挥着大多数其他耐氧细胞中微摩尔浓度超氧化物歧化酶的功能。高浓度的锰（II）通过一种高效的主动运输系统积累，并以高分子量复合物的形式储存在细胞内。对植物乳杆菌的研究提供了一个有趣的例子，即锰在铁的几种生物学作用中替代了铁，这是一种耐氧的替代机制，并且让人们对乳酸菌独特的生物化学有了更好的理解。
