双功能转移酶/脱碳酶LnmK作为聚基酸生物合成中β-化缺失的环节
Tao Liu1, Yong Huang, Ben Shen
1Division of Pharmaceutical Sciences, University of Wisconsin-Madison, Madison, Wisconsin 53705-2222, USA.
Journal of the American Chemical Society
|May 2, 2009
概括
研究人员确定了LnmK,LnmK是一种对多基化生物合成至关重要的酶. 这种双功能转移酶/脱碳酶 (AT/DC) 酶产生乙烯载体蛋白 (ACP),解释了天然产品中β-乙烯分支的起源.
科学领域:
- 生物化学 生物化学
- 自然产品生物合成 自然产品生物合成
- 酶学 是一种酶学.
背景情况:
- β-化是多基体结构多样性的关键.
- 基甲基酸-CoA合成酶同类物催化β-甲基和β-乙基分支,使用乙或propionyl-S-acyl载体蛋白 (ACP).
- 在聚基化物生物合成中,propionyl-S-ACP的来源仍然是未知的.
研究的目的:
- 为了确定负责生成propionyl-S-ACP.的酶.
- 为了阐明在聚基生物合成中的β-乙烯或乙烯分支形成中的缺失环节.
主要方法:
- 从莱纳氨酸生物合成途径中对LnmK酶的表征.
- 酶测试以确定基质特异性和催化活性.
主要成果:
- 鉴定出LnmK是一种双功能转移酶/脱碳酶 (AT/DC).
- LnmK是由甲基马洛尼尔-CoA的propionyl-S-ACP衍生出来的.
- 这一发现解释了聚基化天然产品中β-乙烯或乙烯分支的起源.
结论:
- LnmK代表了一种新的AT/DC酶家族.
- LnmK填补了关于多基化生物合成中的propionyl-S-ACP的知识空白.
- 通过组合生物合成,LnmK提供了通过组合生物合成设计具有β-基分支的新型聚基的潜力.
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