通过计算性酶工程改善Streptomyces antibioticus中的乙-CoA碳酸酶 (AccB) 的基质结合
Imtiaz Ali1, Dong-Qing Wei2, Abbas Khan2,3
1State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, P. R. China.
Biotechnology and applied biochemistry
|January 30, 2024
概括
酶工程发现了三种关键突变 (S343A,T347W,S350W),这些突变显著增强了乙-甲酸碳酸酶 (ACC) 的结合. 这些突变提高了基质结合亲和力,为更高效的多基基和生物燃料的工业生物合成铺平了道路.
科学领域:
- 生物技术是生物技术.
- 生物化学 生化学
- 酶工程是什么? 酶工程是什么?
背景情况:
- 马洛尼尔-CoA是多基基和脂肪酸衍生化合物的关键组成部分,如生物燃料.
- 目前用于生物合成的工程微生物菌株 (大肠杆菌,C. glutamicum,S. cerevisiae) 经常受到低生产率的影响.
研究的目的:
- 使用酶工程方法,提高乙-CoA与乙-CoA碳酸酶 (ACC) 的结合亲和力.
- 为了确定增强基质结合和整体酶效率的特定突变.
主要方法:
- 用局部定向的突变发生法来产生ACC变体.
- 用分子对接模拟来分析改变的结合网络和相互作用.
- 分子动力学模拟评估了蛋白质的稳定性,紧性和运动.
- 无约束能量 (BFE) 的计算验证了突变对基质结合亲和力的影响.
主要成果:
- 三种特定突变 (S343A,T347W,S350W) 显著改善了对ACC的乙-CoA结合.
- 分子对接揭示了突变分子中增强的结合网络和乙-CoA内部尾巴的稳定.
- 分子模拟表明突变酶具有明显的动态性质和稳定性增加.
- BFE计算证实了对突变体的增强结合亲和力,其值在-55.87至-60.52 kcal/mol之间,而野生类型的 -52.66 kcal/mol.
结论:
- 鉴定出的突变是ACC.中增强基质结合的关键热点.
- 这些工程 ACC 变种显示出更高的结合亲和力和稳定性,为改善工业生物合成过程提供了潜力.
- 这些发现为进一步优化微生物菌株提供了基础,以便有效地生产有价值的化合物.
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