在氧沙酸脱碳酶中双酸基质结合模式
Alvaro Montoya1, Megan Wisniewski1, Justin L Goodsell1
1Department of Chemistry, University of Florida, P.O. Box 117200, Gainesville, FL 32611, USA.
Molecules (Basel, Switzerland)
|September 28, 2024
概括
这项研究揭示了氧沙酸脱酶与氧沙酸二酸结合,而不是单酸,这挑战了以前的模型. 这一发现影响了我们对涉及和二氧化的酶机制的理解.
科学领域:
- 生物化学 生物化学
- 酶动力学 酶动力学
- 生物有机化学 生物有机化学
背景情况:
- 氧沙酸脱碳酶 (EC 4.1.1.2) 是一种依赖Mn和O2的酶,对氧沙酸代谢至关重要.
- 现有的模型建议单酸盐与基质结合,以方便二氧化物进入,尽管酸盐更喜欢双酸盐的协调.
研究的目的:
- 通过实验和计算方法研究氧酸盐脱碳酶的基质结合模式.
- 修订关于氧酸盐脱碳酶中基质结合和二氧化物相互作用的机制性假设.
主要方法:
- 在X波段的13C电子核双共振 (ENDOR) 光谱检测13C标记的酸盐.
- 基于域的局部对自然轨道合集群单双计算 (DLPNO-CCSD).
- 密度函数理论 (DFT) Active Site 模型的几何优化.
主要成果:
- 恩多尔的实验表明,在不同的条件和酶变异中,酸盐与活性位点Mn (II) 离子的双酸盐 (κO, κO') 结合.
- 计算方法预测了Endor光谱与双结合一致,并表明它在能量上比单结合更受青.
- 能量偏好的双酸结合使实验数据相协调,并挑战了关于二氧化物结合的先前假设.
结论:
- 氧沙酸脱碳酶将其基质,氧沙酸,以双重方式与活性位点Mn(II) 离子结合.
- 这一发现需要对现有的机制模型进行修订,特别是关于二氧化碳的作用和结合点的模型.
- 这些结果支持了一种经过修订的机制,涉及用于基质激活的远程电子转移.
关键词:
恩多尔 (英语:Endor,英语:Endor,英语:Endor,英语:Endor,英语:Endor,英语:Endor,英语:Endor,英语:Endor,英语:Endor,英语:Endor,英语:Endor,英语:Endor,英语:Endor.两个数据的协调.氧酸盐脱碳酶酶是一种氧酸脱碳酶.结合基质的基底更多相关视频
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