发现,结构和机制的II类塞斯基环酶
Xingming Pan1, Wenyu Du1, Xiaowei Zhang1
1State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 211198, Jiangsu, China.
Journal of the American Chemical Society
|November 23, 2022
概括
研究人员从Streptomyces发现了新型的II类旋酶 (TCs),揭示了它们独特的结构和诱导适应机制. 这一发现促进了对这些酶的理解,并有助于合成生物学中的TC工程.
科学领域:
- 生物化学和分子生物学
- 酵素学
- 自然产品生物合成
背景情况:
- 环酶 (TCs) 是合成各种天然产品的关键酶.
- 一类TC的特征很好,但二类TC的机理性理解较少.
- 二级TC在细菌的二次代谢中起着重要作用.
研究的目的:
- 发现并对Streptomyces中的新型II类基环 (STC) 进行结构性表征.
- 阐明这些新发现的II类STC的作用机制.
- 为未来的工程应用提供II类TC的酶学见解.
主要方法:
- 在Streptomyces物种中进行基因挖掘以确定潜在的II类STC.
- 用X射线结晶学来确定与基质和辅助因子复合的高分辨率结构.
- 用于分析酶活性和机制的生物化学测试.
主要成果:
- 来自Streptomyces的两种新型II类STCs,三二酸盐合成酶 (DMSs),表现出β,γ-二域结构.
- 在SsDMS中,结构性表征揭示了诱导适合机制和前所未有的Mg2+结合模式.
- 这些发现为规范II类TC酶学提供了第一个详细的机理洞察.
结论:
- 这项研究成功地描述了新型II类TC,扩大了这些酶的已知多样性.
- 阐明的诱导适合机制和Mg2+结合模式解决了II类TC酶学中的关键问题.
- 这些发现支持细菌TC的持续探索,并为TC工程和合成生物学进步提供基础.
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