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通过路径合和介导形成的塔西卡米德生物合成
Guang-Lei Ma1, Hartono Candra1, Li Mei Pang1
1School of Biological Sciences, Nanyang Technological University, 637551 Singapore.
Journal of the American Chemical Society
|January 21, 2022
概括
研究人员发现了新型微生物代谢物 - - 塔西卡米德,具有独特的循环支架和连接. 它们的生物合成涉及两个基因集群和前所未有的体内Japp-Klingemann反应,揭示了天然产品形成的新途径.
科学领域:
- 自然产品化学
- 微生物代谢学
- 生物合成途径
背景情况:
- 自然存在的水很少见,与在有机合成和材料科学中广泛使用的合成类似物形成鲜明对比.
- 循环是常见的微生物代谢物,但它们通过链接与其他部分的结合是不寻常的.
研究的目的:
- 发现并描述具有独特结构特征的新型微生物代谢物.
- 阐明这些新化合物的生物合成途径,重点关注链的形成.
- 探索参与生物合成的酶的潜在应用.
主要方法:
- 微生物代谢物tasikamides A-C的分离和结构阐明.
- 基因组分析以确定对代谢物生物合成负责的基因群.
- 生物化学测定以表征酶活动,包括二化和合反应.
主要成果:
- 发现了tasikamides,新型循环五,通过水键连接到基5氨酸 (AHA) 部分.
- 确定两个不同的基因群:一个用于循环架 (NRPS),另一个用于AHA生物合成.
- 一种新生物合成机制的阐释,包括AHA的二化和随后的非酶的Japp-Klingemann合与前体.
结论:
- 塔西卡米德是一种通过独特的双通道生物合成形成的新型微生物天然产品.
- 一个前所未有的活体Japp-Klingemann反应是形成tasikamides中的链的关键.
- 亚胺-亚化酶 (AAD) 具有活体合成亚化合物和生物大分子修饰的潜力.
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