Manganous cation | 16397-91-4

• 分子结构分类: 无机化合物 - 均相金属化合物 - 均相过渡金属化合物
• 英文名称: Manganous cation
• 英文别名: manganese(2+)
• CAS: 16397-91-4
• 化学式: Mn+2
• 分子量: 54.93804
• InChiKey: WAEMQWOKJMHJLA-UHFFFAOYSA-N

物化性质

• 物理描述：
  Solid
• 沸点：
  2061
• 熔点：
  1244°C

计算性质

• 辛醇/水分配系数(LogP)：
  -0.0
• 重原子数：
  1
• 可旋转键数：
  0
• 环数：
  0.0
• sp3杂化的碳原子比例：
  0.0
• 拓扑面积：
  0
• 氢给体数：
  0
• 氢受体数：
  0

ADMET

代谢

锰主要通过摄入被吸收，但也可以通过吸入。它在血浆中与α-2-巨球蛋白、白蛋白或转铁蛋白结合，并分布到大脑和所有其他哺乳动物组织，尽管它倾向于在肝脏、胰腺和肾脏中积累更多。锰存在多种氧化态，并且据信在体内会经历氧化态的变化。锰的氧化态可以影响组织的毒物动力学行为，也可能影响毒性。锰主要通过粪便排出。(L228)

Manganese is mainly absorbed via ingestion, but can also be inhaled. It binds to alpha-2-macroglobulin, albumin, or transferrin in the plasma and is distributed to the brain and all other mammalian tissues, though it tends to accumulate more in the liver, pancreas, and kidney. Manganese exists in a number of oxidation states and is believed to undergo changes in oxidation state within the body. Manganese oxidation state can influence tissue toxicokinetic behavior, and possibly toxicity. Manganese is excreted primarily in the faeces. (L228)

来源:Toxin and Toxin Target Database (T3DB)

毒理性

• 毒性总结

锰是一种细胞毒素，可以损害运输系统、酶活性和受体功能。它主要针对中枢神经系统，尤其是基底神经节中的苍白球。人们认为，锰离子Mn(II)增强了各种细胞内儿茶酚胺的自动氧化或转换，导致自由基、活性氧种和其他细胞毒素代谢产物的产生增加，同时耗尽细胞的抗氧化防御机制，导致氧化损伤和选择性破坏多巴胺能神经元。除了多巴胺，人们还认为锰会与其它神经递质相互作用，如GABA和谷氨酸。锰会过度激活锰超氧化物歧化酶并产生氧化损伤。Mn(II)的神经毒性还与其在生理条件下取代Ca(II)的能力有关。它可以通过钙单向转运体进入线粒体并抑制线粒体氧化磷酸化。它还可能抑制Ca(II)的外排，这可能导致线粒体膜完整性的丧失。Mn(II)已被证明能显著抑制线粒体顺乌头酸酶活性，改变氨基酸代谢和细胞铁稳态。(L228)

Manganese is a cellular toxicant that can impair transport systems, enzyme activities, and receptor functions. It primarily targets the central nervous system, particularily the globus pallidus of the basal ganglia. It is believed that the manganese ion, Mn(II), enhances the autoxidation or turnover of various intracellular catecholamines, leading to increased production of free radicals, reactive oxygen species, and other cytotoxic metabolites, along with a depletion of cellular antioxidant defense mechanisms, leading to oxidative damage and selective destruction of dopaminergic neurons. In addition to dopamine, manganese is thought to interact with other neurotransmitters, such as GABA and glutamate. Manganese overwhelms the manganese superoxide dismutase and produce oxidative damage. The neurotoxicity of Mn(II) has also been linked to its ability to substitute for Ca(II) under physiological conditions. It can enter mitochondria via the calcium uniporter and inhibit mitochondrial oxidative phosphorylation. It may also inhibit the efflux of Ca(II), which can result in a loss of mitochondrial membrane integrity. Mn(II) has been shown to inhibit mitochondrial aconitase activity to a significant level, altering amino acid metabolism and cellular iron homeostasis. (L228)

来源:Toxin and Toxin Target Database (T3DB)

毒理性

• 致癌物分类

对人类不具有致癌性（未被国际癌症研究机构IARC列名）。

No indication of carcinogenicity to humans (not listed by IARC).

来源:Toxin and Toxin Target Database (T3DB)

毒理性

• 健康影响

锰主要影响神经系统，可能导致行为改变和其他神经系统效应，包括动作可能变得缓慢和笨拙。这些症状足够严重时，被称为“锰症”。高水平的锰也可能对生殖系统造成损害。

Manganese mainly affects the nervous system and may cause behavioral changes and other nervous system effects, which include movements that may become slow and clumsy. This combination of symptoms when sufficiently severe is referred to as “manganism”. High levels of manganese may also cause damage to the reproductive system. (L228)

来源:Toxin and Toxin Target Database (T3DB)

毒理性

• 暴露途径

口服（L228）；吸入（L228）

Oral (L228) ; inhalation (L228)

来源:Toxin and Toxin Target Database (T3DB)

毒理性

• 症状

锰主要影响神经系统，可能导致行为改变和其他神经系统效应，包括动作可能变得缓慢和笨拙。这种症状组合在足够严重时被称为“锰中毒”。

Manganese mainly affects the nervous system and may cause behavioral changes and other nervous system effects, which include movements that may become slow and clumsy. This combination of symptoms when sufficiently severe is referred to as “manganism”. (L228)

来源:Toxin and Toxin Target Database (T3DB)

反应信息

• 作为反应物：
  描述：

  氢(+1)阳离子 、 双氧水 、 Manganous cation 生成 水 、 锰离子
  参考文献：
  名称：

  Phanerochaete chrysosporium的木质素酶和Mn过氧化物酶的稳定性测试。

  摘要：

  白腐真菌Phanerochaete chrysosporium产生细胞外过氧化物酶（木质素酶和Mn-过氧化物酶），被认为与木质素降解有关。这些细胞外酶也与生物降解难降解的污染物有关。已经提出木质素酶的商业应用既用于木材的生物机械制浆又用于废水处理。木质素降解酶的体外稳定性将是决定工业应用的经济和技术可行性的重要因素，并且对于优化酶的商业生产也将至关重要。本文介绍了许多变量对木质素酶和Mn-过氧化物酶体外稳定性的影响。发现木质素酶的热稳定性通过增加pH值和通过增加酶浓度而改善。对于固定的pH和酶浓度，存在底物藜芦醇（3,4-二甲氧基苄醇）时，木质素酶的稳定性大大提高。还发现木质素酶在第二阶段的过程中被过氧化氢灭活，该过程被认为涉及非反应性过氧化物酶中间体化合物III的形成。Mn-过氧化物酶不易被过氧化物灭活，这对应于其他人的观察结果，即Mn-过氧化物酶的化合物III比木质素酶的化合物III形

  DOI：

  10.1002/bit.260341003

文献信息

• Stability testing of ligninase and Mn-peroxidase fromPhanerochaete chrysosporium
  作者：Michael D. Aitken、Robert L. Irvine

  DOI：10.1002/bit.260341003

  日期：1989.12.5

  of variables on in vitro stability of ligninase and Mn-peroxidase are presented in this paper. Thermal stability of ligninase was found to improve by increasing pH and by increasing enzyme concentration. For a fixed pH and enzyme concentration, ligninase stability was greatly enhanced in the presence of its substrate veratryl alcohol (3,4-dimethoxybenzyl alcohol). Ligninase also was found to be inactivated

  白腐真菌Phanerochaete chrysosporium产生细胞外过氧化物酶（木质素酶和Mn-过氧化物酶），被认为与木质素降解有关。这些细胞外酶也与生物降解难降解的污染物有关。已经提出木质素酶的商业应用既用于木材的生物机械制浆又用于废水处理。木质素降解酶的体外稳定性将是决定工业应用的经济和技术可行性的重要因素，并且对于优化酶的商业生产也将至关重要。本文介绍了许多变量对木质素酶和Mn-过氧化物酶体外稳定性的影响。发现木质素酶的热稳定性通过增加pH值和通过增加酶浓度而改善。对于固定的pH和酶浓度，存在底物藜芦醇（3,4-二甲氧基苄醇）时，木质素酶的稳定性大大提高。还发现木质素酶在第二阶段的过程中被过氧化氢灭活，该过程被认为涉及非反应性过氧化物酶中间体化合物III的形成。Mn-过氧化物酶不易被过氧化物灭活，这对应于其他人的观察结果，即Mn-过氧化物酶的化合物III比木质素酶的化合物III形
• Characterization of reactions catalyzed by manganese peroxidase from Phanerochaete chrysosporium
  作者：Michael D. Aitken、Robert L. Irvine

  DOI：10.1016/0003-9861(90)90739-l

  日期：1990.2

  consumed approaches 2:1 as enzyme concentration increases at a fixed concentration of peroxide or as peroxide concentration decreases at a fixed enzyme concentration. Reduced stoichiometry below 2:1 is shown to be due to Mn(III) complex decomposition by hydrogen peroxide. Reaction of Mn(III) with peroxide is catalyzed by Cu(II), which explains an apparent inhibition of MnP by Cu(II). The net decomposition

  锰过氧化物酶（MnP）是被认为与白腐担子菌Phanerochaete chrysosporium参与木质素生物降解的两种细胞外过氧化物酶之一。该酶将Mn（II）氧化为Mn（III），后者在Mn（III）稳定配体的存在下积累。Mn（III）配合物又可以氧化多种有机底物。随着酶浓度在固定的过氧化物浓度下增加或过氧化物的浓度在固定的酶浓度下减少，每个消耗的过氧化氢形成的Mn（III）配合物的化学计量接近2：1。化学计量比降低至2：1以下是由于过氧化氢分解了Mn（III）络合物所致。Mn（III）与过氧化物的反应是由Cu（II）催化的，这说明了Cu（II）明显抑制了MnP。过氧化氢的净分解形成分子氧似乎也是在不充当Mn（III）稳定配体的缓冲液中唯一可观察到的反应。Mn（III）和过氧化物的非生产性分解是一个重要发现，对提议的酶的体外用途及其在木质素降解中的作用具有重要意义。本文还描述了由该酶形成
• Comparison of ligninase-I and peroxidase-M2 from the white-rot fungus Phanerochaete chrysosporium
  作者：Andrzej Paszczyński、Van-Ba Huynh、Ronald Crawford

  DOI：10.1016/0003-9861(86)90644-2

  日期：1986.2

  required Mn2+ ions to accomplish a similar cycle. The peroxidase oxidized Mn2+ to a higher oxidation state, and the oxidized Mn acted as a diffusible catalyst able to oxidize numerous organic substrates. Unlike ligninase-I which is found free extracellularly, peroxidase-M2 appears to be associated closely with the fungal mycelium. In its peroxidatic reactions, ligninase-I oxidizes a variety of nonphenolic

  木质素酶I（Mr 42,000-43,000;碳水化合物，21％）和过氧化物酶-M2（Mr 45,000-47,000;碳水化合物，17％），是两种典型的依赖于过氧化氢的白腐真菌Phanerochaete的木质素分解培养物产生的细胞外酶。纯化了金孢菌BKM-F-1767，并比较了它们的性质。光谱研究表明，两种天然酶都是含有原卟啉IX的血红素蛋白。EPR光谱表明，铁离子作为高自旋亚铁血红素复合物与酶的辅基团配合。我们证实了其他报道，木质素酶-过氧化氢复合物（活化酶）在加入连二亚硫酸盐或一种酶的底物（例如藜芦醇）后恢复为天然状态。然而，我们发现过氧化物酶-M2-过氧化氢络合物需要Mn2 +离子才能完成类似的循环。过氧化物酶将Mn2 +氧化为更高的氧化态，并且氧化后的Mn用作能够氧化多种有机底物的可扩散催化剂。与在细胞外游离的木质素酶-I不同，过氧化物酶-M2似乎与真菌菌丝体紧密相关。在其过氧化
• Elimination of Manganese(II,III) Oxidation in Pseudomonas putida GB-1 by a Double Knockout of Two Putative Multicopper Oxidase Genes
  作者：Kati Geszvain、James K. McCarthy、Bradley M. Tebo

  DOI：10.1128/aem.01850-12

  日期：2013.1

  Bacterial manganese(II) oxidation impacts the redox cycling of Mn, other elements, and compounds in the environment; therefore, it is important to understand the mechanisms of and enzymes responsible for Mn(II) oxidation. In several Mn(II)-oxidizing organisms, the identified Mn(II) oxidase belongs to either the multicopper oxidase (MCO) or the heme peroxidase family of proteins. However, the identity of the oxidase in Pseudomonas putida GB-1 has long remained unknown. To identify the P. putida GB-1 oxidase, we searched its genome and found several homologues of known or suspected Mn(II) oxidase-encoding genes ( mnxG , mofA , moxA , and mopA ). To narrow this list, we assumed that the Mn(II) oxidase gene would be conserved among Mn(II)-oxidizing pseudomonads but not in nonoxidizers and performed a genome comparison to 11 Pseudomonas species. We further assumed that the oxidase gene would be regulated by MnxR, a transcription factor required for Mn(II) oxidation. Two loci met all these criteria: PputGB1_2447, which encodes an MCO homologous to MnxG, and PputGB1_2665, which encodes an MCO with very low homology to MofA. In-frame deletions of each locus resulted in strains that retained some ability to oxidize Mn(II) or Mn(III); loss of oxidation was attained only upon deletion of both genes. These results suggest that PputGB1_2447 and PputGB1_2665 encode two MCOs that are independently capable of oxidizing both Mn(II) and Mn(III). The purpose of this redundancy is unclear; however, differences in oxidation phenotype for the single mutants suggest specialization in function for the two enzymes.

  摘要 细菌的锰（II）氧化作用会影响环境中锰、其他元素和化合物的氧化还原循环；因此，了解锰（II）氧化作用的机制和负责氧化的酶非常重要。在几种锰（II）氧化生物中，已确定的锰（II）氧化酶属于多铜氧化酶（MCO）或血红素过氧化物酶家族蛋白。然而，在 假单胞菌 GB-1 中氧化酶的身份长期以来一直不为人知。为了确定 假单胞菌 GB-1 氧化酶，我们搜索了它的基因组，发现了几个已知或疑似 Mn（II）氧化酶编码基因的同源物（mnxGG、mnxGG、mnxGG、mnxGG 和 mnxG , mofA , moxA 和 mopA ).为了缩小该列表的范围，我们假定锰（II）氧化酶基因在氧化锰（II）的假单胞菌中是保守的，而在非氧化锰（II）的假单胞菌中则不保守，因此对 11 个假单胞菌的基因组进行了比较。 假单胞菌 物种进行了基因组比较。我们还进一步假设氧化酶基因将受 MnxR 的调控，MnxR 是 Mn（II）氧化所需的转录因子。有两个基因位点符合所有这些标准：PputGB1_2447 编码与 MnxG 同源的 MCO，而 PputGB1_2665 编码与 MofA 同源性极低的 MCO。每个基因座的框内缺失都会导致菌株保留一定的氧化锰（II）或锰（III）的能力；只有同时缺失两个基因时才会丧失氧化能力。这些结果表明，PputGB1_2447 和 PputGB1_2665 编码两种 MCO，它们能够独立氧化 Mn(II) 和 Mn(III)。这种冗余的目的尚不清楚；但是，单个突变体氧化表型的差异表明这两种酶的功能具有特异性。
• CotA, a Multicopper Oxidase from Bacillus pumilus WH4, Exhibits Manganese-Oxidase Activity
  作者：Jianmei Su、Peng Bao、Tenglong Bai、Lin Deng、Hui Wu、Fan Liu、Jin He

  DOI：10.1371/journal.pone.0060573

  日期：——

  Multicopper oxidases (MCOs) are a family of enzymes that use copper ions as cofactors to oxidize various substrates. Previous research has demonstrated that several MCOs such as MnxG, MofA and MoxA can act as putative Mn(II) oxidases. Meanwhile, the endospore coat protein CotA from Bacillus species has been confirmed as a typical MCO. To study the relationship between CotA and the Mn(II) oxidation, the cotA gene from a highly active Mn(II)-oxidizing strain Bacillus pumilus WH4 was cloned and overexpressed in Escherichia coli strain M15. The purified CotA contained approximately four copper atoms per molecule and showed spectroscopic properties typical of blue copper oxidases. Importantly, apart from the laccase activities, the CotA also displayed substantial Mn(II)-oxidase activities both in liquid culture system and native polyacrylamide gel electrophoresis. The optimum Mn(II) oxidase activity was obtained at 53°C in HEPES buffer (pH 8.0) supplemented with 0.8 mM CuCl2. Besides, the addition of o-phenanthroline and EDTA both led to a complete suppression of Mn(II)-oxidizing activity. The specific activity of purified CotA towards Mn(II) was 0.27 U/mg. The Km, Vmax and kcat values towards Mn(II) were 14.85±1.17 mM, 3.01×10−6±0.21 M·min−1 and 0.32±0.02 s−1, respectively. Moreover, the Mn(II)-oxidizing activity of the recombinant E. coli strain M15-pQE-cotA was significantly increased when cultured both in Mn-containing K liquid medium and on agar plates. After 7-day liquid cultivation, M15-pQE-cotA resulted in 18.2% removal of Mn(II) from the medium. Furthermore, the biogenic Mn oxides were clearly observed on the cell surfaces of M15-pQE-cotA by scanning electron microscopy. To our knowledge, this is the first report that provides the direct observation of Mn(II) oxidation with the heterologously expressed protein CotA, Therefore, this novel finding not only establishes the foundation for in-depth study of Mn(II) oxidation mechanisms, but also offers a potential biocatalyst for Mn(II) removal.

  多铜氧化酶（MCOs）是一个利用铜离子作为辅助因子氧化各种底物的酶家族。以往的研究表明，MnxG、MofA 和 MoxA 等几种多铜氧化酶可作为假定的 Mn（II）氧化酶。同时，芽孢杆菌的内孢子衣壳蛋白 CotA 也被证实是一种典型的 MCO。为了研究 CotA 与锰(II)氧化之间的关系，克隆了高活性锰(II)氧化菌株 Bacillus pumilus WH4 的 cotA 基因，并在大肠杆菌菌株 M15 中进行了过表达。纯化的 CotA 每个分子含有大约四个铜原子，并显示出典型的蓝铜氧化酶光谱特性。重要的是，除了漆酶活性外，CotA 还在液体培养系统和原生聚丙烯酰胺凝胶电泳中显示出大量的锰（II）氧化酶活性。在添加了 0.8 mM CuCl2 的 HEPES 缓冲液（pH 8.0）中，锰（II）氧化酶活性在 53°C 时达到最佳。此外，加入邻菲罗啉和乙二胺四乙酸都会完全抑制锰（II）氧化活性。纯化的 CotA 对锰（II）的比活度为 0.27 U/mg 。对 Mn(II) 的 Km、Vmax 和 kcat 值分别为 14.85±1.17 mM、3.01×10-6±0.21 M-min-1 和 0.32±0.02 s-1。此外，重组大肠杆菌菌株 M15-pQE-cotA 在含锰 K 液体培养基和琼脂平板上的氧化锰（II）活性均显著提高。经过 7 天的液体培养，M15-pQE-cotA 从培养基中清除了 18.2% 的 Mn（II）。此外，通过扫描电子显微镜，我们还在 M15-pQE-cotA 的细胞表面清晰地观察到了生物锰氧化物。据我们所知，这是第一份利用异源表达蛋白 CotA 直接观察锰（II）氧化作用的报告。因此，这一新颖的发现不仅为深入研究锰（II）氧化机制奠定了基础，而且为去除锰（II）提供了一种潜在的生物催化剂。