Activation of the methylreductase system from Methanobacterium bryantii by corrins.
Activation of the methylreductase system from Methanobacterium bryantii by corrins.
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Corrins 激活布氏甲烷杆菌的甲基还原酶系统。
DOI：
10.1128/jb.164.1.165-172.1985
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发表时间：
1985
影响因子：
3.2
通讯作者：
Wolfe,RS
中科院分区：
文献类型：
--
作者：
Whitman,WB;Wolfe,RS
在从低分子量因子中提取的提取物中，Corrins激活了来自Bryantii甲烷杆菌的甲基还原酶系统三到五倍。Corrins不能替代ATP和组分B，它们也是最大活性所需的。二水合二氨酰胺达到一半最大活性所需的浓度为1 μ M。半数最大活性所需的氰钴胺、甲钴胺、钴α-（5-羟基苯并咪唑基）-钴β-氰钴酰胺和5 ′-脱氧腺苷钴酰胺的浓度在4和7 μ M之间。脱氧腺苷钴胺素几乎没有活性。活化是独立的硫醇，辅酶M，和ATP。通过琼脂糖柱层析部分纯化甲基还原酶系统后也观察到活化。在催化浓度下需要Corrin，不需要甲钴胺，并且甲烷生成是酶促的。咕啉对甲基还原酶的激活是一种新的甲烷生成效应。然而，咕啉激活的生理意义是不确定的。
Corrins activated the methylreductase system from Methanobacterium bryantii three- to fivefold in extracts resolved from low-molecular-weight factors. Corrins did not substitute for ATP and component B, which were also required for maximal activity. The concentration of diaquacobinamides required for one-half maximal activity was 1 microM. The concentrations of cyanocobalamin, methylcobalamin, Co alpha-(5-hydroxybenzimidazoyl)-Co beta-cyanocobamide, and 5'-deoxyadenosylcobinamide required for one-half maximal activity were between 4 and 7 microM. Deoxyadenosylcobalamin was nearly inactive. Activation was independent of thiols, coenzyme M, and ATP. Activation was also observed after partial purification of the methylreductase system by agarose column chromatography. Corrins were required in catalytic concentrations, methylcobalamin was not required, and methanogenesis was enzymatic. Corrin activation of the methylreductase is a novel effect on methanogenesis. However, the physiological significance of the corrin activation is uncertain.