提亚酸天然产品的化学酶合成,其中包括一种酶催化形式的 [4 + 2] 循环添加
Walter J Wever1, Jonathan W Bogart1, Joshua A Baccile2
1†Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States.
Journal of the American Chemical Society
|March 6, 2015
概括
研究人员确定了TclM,这是催化硫抗生素生物合成的最后一步的酶. 这涉及脱氨酸之间独特的 [4+2] 循环添加反应,完成了 thiazolyl 路径.
科学领域:
- 生物化学 生物化学
- 自然产品化学 自然产品化学
- 酶学 是一种酶学.
背景情况:
- 铁西林是由Bacillus cereus生产的 thiazolyl 类抗生素.
- 它们的生物合成涉及前体的翻译后修改.
- 最后的循环化步骤以前没有被描述.
研究的目的:
- 为了酶性地描述硫林生物合成的最后一步.
- 为了确定负责拟议的 [4+2] 循环添加的酶.
- 开发一种生产复杂基质的方法.
主要方法:
- 使用原生化学结合 (NCL) 的铁素前体的化学酶合成.
- 生物化学试验测试TclM酶的活性.
- 由TclM催化的 [4+2]循环添加反应的特征.
主要成果:
- 鉴定了单个酶TclM,并证明它可催化两个脱水氨酸之间的正式 [4+2] 循环添加.
- 这种反应代表了硫林生物合成的最后一步.
- 建立了一条通往复杂基质的新型化学酶途径.
结论:
- 酶TclM负责硫林生物合成中独特的循环添加反应.
- 这一发现阐明了 thiazolyl 的天然产品形成的关键步骤.
- 开发的化学酶策略可以进一步研究这种酶类和抗生素生产.
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