维生素B的细胞金属化有两个不同的热力学梯度12
Tessa R Young1,2, Evelyne Deery3, Andrew W Foster1,2
1Department of Biosciences, Durham University, Durham DH1 3LE, U.K.
JACS Au
|May 26, 2023
概括
维生素B12的插入通过早期或晚期的途径发生. 晚期的途径使用CobW金属沙佩龙来克服不利的热力学,合转移到GTP水解.
科学领域:
- 生物化学 生物化学
- 生物有机化学 生物有机化学
- 分子生物学分子生物学
背景情况:
- 维生素B12的生物合成涉及到将嵌到corrin环中.
- 存在两种途径:早期 (金属单元独立) 和晚期 (金属单元依赖).
- 晚期的途径使用了CobW金属沙佩龙,G3E GTPase.
研究的目的:
- 为了对比嵌在metallochaperone-dependent和-independent路径中的嵌的热力学.
- 阐明CobW金属沙佩龙在克服热力学障碍中的作用.
- 研究维生素B12生物合成期间转移的机制.
主要方法:
- 使用了 (II) 缓冲酶定量.
- 分析了转移的热力学梯度.
- 在GTP水解方面研究了CobW金属沙佩龙的功能.
主要成果:
- 金属沙佩龙独立路径 (CbiK 酶) 显示了对插入有利的热力学梯度.
- 金属沙佩龙依赖性途径 (CobNST 酶) 对结合具有非常不利的热力学梯度.
- CobW通过将其合到GTP水解来促进转移,克服不利的梯度.
结论:
- 在CobW金属沙佩龙是克服热力学挑战在晚期嵌途径至关重要的.
- 通过CobW的GTP水解驱动了的能量不利转移到酶复合体.
- 这项研究揭示了一种复杂的机制,用于在维生素B12生物合成中通过金属沙佩龙介导的金属插入.
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