MANGANESE CATALYSIS OF DOPAMINE OXIDATION
MANGANESE CATALYSIS OF DOPAMINE OXIDATION
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DOI：
10.1016/0048-9697(89)90036-3
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发表时间：
1989-01-01
影响因子：
9.8
通讯作者：
STAUBER, JL
中科院分区：
文献类型：
--
作者：
FLORENCE, TM;STAUBER, JL
研究了锰对空气氧化多巴胺的催化作用，作为对生活在澳大利亚北领地格鲁特岛富含锰的土壤上的一群原住民可能的锰中毒调查的一部分。锰显着提高多巴胺的氧化速率，并且锰与某些嘌呤的络合物是特别有效的催化剂。提出了一种涉及锰(II)/(III)氧化还原对和半醌自由基中间体的氧化机制。氧化产生化学计量的过氧化氢，多巴胺的氧化产物对海洋硅藻新月菱形藻有剧毒。过氧化氢和超氧自由基在生理pH值下不氧化多巴胺。一些亲电子化合物，包括抗坏血酸、脱氢抗坏血酸和硫胺素，可以有效抑制多巴胺氧化。格鲁特岛原住民可能缺乏抗坏血酸（维生素 C）和硫胺素（维生素 B1），这些缺乏以及他们的生活方式可能使他们容易患锰中毒。
Manganese catalysis of the oxidation of dopamine by air was studied as part of an investigation of possible manganese intoxication amongst a group of Aborigines living on manganese-rich soil on Groote Eylandt, in the Northern Territory of Australia. Manganese significantly increased the oxidation rate of dopamine, and the manganese complexes with some purines were especially efficient catalysts. An oxidation mechanism, involving a manganese(II)/(III) redox couple and a semiquinone free radical intermediate, is proposed. Stoichiometric hydrogen peroxide was produced by the oxidation, and the oxidation products of dopamine were highly toxic to the marine diatom Nitzschia closterium. Hydrogen peroxide and the superoxide radical did not oxidize dopamine at physiological pH. Some electrophilic compounds, including ascorbic acid, dehydroascorbic acid and thiamine, effectively inhibited dopamine oxidation. The Groote Eylandt Aborigines are likely to be deficient in ascorbic acid (vitamin C) and thiamine (vitamin B1), and these deficiencies, as well as their lifestyle, may predispose them to manganese intoxication.