在基质结合时的 conformational switch 告知了 CCoAOMT 酶的合理设计
Yujie Cao1,2, Xinru Yue2, Wentong Yu2
1Bamboo & Forest Institute of Science, Technology and Industrial Innovation, Leshan Normal University, Leshan, 614004, China.
Scientific reports
|October 21, 2025
概括
这项研究揭示了caffeoyl共酶A O-甲基转移酶 (CCoAOMT) 如何通过分析分子动力学来结合其基质CCoA. 了解这些相互作用是设计酶的关键,以减少造纸业中的红素.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 计算化学计算化学
背景情况:
- 木是造纸行业的主要来源,但红素生产产生了大量的工业污染.
- 减少造纸中的素含量可以提高纸产量,减少化学试剂的使用和污染物产生.
- 咖啡因共酶AO-甲基转移酶 (CCoAOMT) 调节素生物合成,但其基质识别机制尚不清楚.
研究的目的:
- 阐明CCoAOMT在结合其基质咖啡醇辅酶A (CCoA) 时的分子识别机制和构造变化.
- 确定关键的残留物和参与基质结合和全调节的区域.
- 为设计具有改变活性的酶提供见解,用于工业应用.
主要方法:
- 进行比较分子动力学 (MD) 模拟以分析整体结构变化.
- 自由能源景观 (FEL) 和形状集群分析,以调查功能运动模式.
- 适应式指导分子动力学 (ASMD) 模拟来观察基质识别和全ostery.
- 具有约束力的自由能量预测和能量分解,以确定关键的残留物.
- 单一突变和折叠计算以评估酶活性.
主要成果:
- 在结合口袋 (α1,α2,α6,α8) 外的区域中,CCoAOMT表现出更大的灵活性,从而促进基质结合.
- 功能运动涉及β5,α2和α8区域,酶的运输通道在基质结合时从开放过渡到关闭.
- 关键残留物 (例如,Y188,D218) 形成关键的键,定CCoA基质.
- 已经确定了6种潜在的低活性CCoAOMT突变 (K1L,N39G,I40P,T42N,N174D,D218V).
结论:
- 这项研究阐明了CCoAOMT的动态构造变化和基质识别过程.
- 确定了关键的残留物和区域,为酶工程提供了控制素生物合成的基础.
- 这些发现有助于通过优化素含量来开发更可持续的造纸工艺.
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