通过RapL进行pipecolic酸的生物合成,这是一种在拉帕米基因集群中编码的 lysine cyclodeaminase
Gregory J Gatto1, Michael T Boyne, Neil L Kelleher
1Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.
Journal of the American Chemical Society
|March 16, 2006
概括
这项研究验证了酶RapLL的有效性.
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:
- 拉巴胺素,FK506和FK520是重要的免疫抑制剂.
- 这些自然产品含有pipecolic酸残留物.
- 皮佩科力酸是通过氨酸循环氨基化生物合成的.
研究的目的:
- 为了研究酶RapL在pipecolic酸生物合成中的功能.
- 描述氨酸循环胺化的催化机制.
- 为了提供第一个在体外描述 lysine cyclodeaminase.
主要方法:
- 对RapL酶的异种过度表达和净化.
- 使用L-lysine和L-ornithine作为基质的酶分析.
- 以同位素标记的基板来确认机械细节.
- 谱分析以确定辅助因子的要求.
主要成果:
- 拉普尔通过循环氨基化成功将L-lysine转化为L-pipecolic acid.
- 该反应涉及与尼古丁胺胺氨基二核酸 (NAD+) 的氧化还原催化.
- 与L-ornithine相比,RapL的效率较低,并且需要NAD+进行最佳活动.
- 机理学研究证实了氨酸的损失和α-碳的保持.
结论:
- 拉普L是重要的免疫抑制剂的生物合成中的关键酶.
- 这项工作阐明了氨酸循环胺化的机制.
- 这项研究强调了NAD+在这种独特的酶转化中的作用.
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