在amicetin中表征阿莫胺生物合成,揭示了AmiG是一种可逆的保留甘氨基转移酶
Ruidong Chen1, Haibo Zhang, Gaiyun Zhang
1CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, RNAM Center for Marine Microbiology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, 164 West Xingang Road, Guangzhou 510301, China.
Journal of the American Chemical Society
|August 8, 2013
概括
研究人员研究了阿莫胺生物合成,确定了关键酶AmiH和AmiG. 甘氨基转移酶AmiG显示了催化逆转性和基质灵活性,为新型核酸抗生素开发提供了潜力.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 自然产品生物合成 自然产品生物合成
背景情况:
- 艾米西丁是一种分糖核酸抗生素,具有独特的α-(1→4) - - 葡萄糖酸键.
- 保持糖化是amicetin生物合成的一个关键特征.
研究的目的:
- 研究阿莫胺生物合成中的两个关键步骤.
- 描述糖系转移酶AmiG及其在阿莫化中的作用.
- 探索AmiG在多样化核酸抗生素中的潜力.
主要方法:
- 酶试验以确定N-甲基转移酶AmiH和甘氨基转移酶AmiG的功能.
- 生物化学和动力学特征的AmiG.
- 对AmiG的基质灵活性和交换反应分析.
主要成果:
- AmiH对于阿莫胺二甲基化是必不可少的.
- 对于 amosaminylation,AmiG 是必要的.
- 艾米G表现出催化可逆性,这是一个新发现,用于在二次代谢物生物合成中保留糖系转移酶.
- 艾米G与各种糖核酸具有基质灵活性,并易受糖和甘的交换.
结论:
- 艾米G是阿莫胺生物合成中的关键酶.
- AmiG的催化可逆性和基质灵活性为设计新型核酸抗生素提供了机会.
- 这项研究为对天然产品保留甘氨酸转移酶的机制研究提供了基础.
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