具有前所未有的酶变化的l-亚酸盐化途径的表征
Tyler M M Stack1, Katelyn N Morrison2, Thomas M Dettmer2
1Carl R. Woese Institute for Genomic Biology , University of Illinois , Urbana , Illinois 61801 , United States.
Journal of the American Chemical Society
|January 10, 2020
概括
通过新发现的代谢途径,Ralstonia eutropha H16利用维生素C (l-ascorbate) 作为其唯一的碳来源. 这一途径涉及分解酸盐的独特酶,为细菌营养和潜在的生物技术应用提供了洞察力.
科学领域:
- 微生物学
- 生物化学
- 代谢工程
背景情况:
- 亚酸盐 (维生素C) 是一种常见的饮食和环境化合物.
- 对于生物技术和环境科学来说,了解微生物对不同碳来源的利用至关重要.
- 细菌中l-ascorbate的代谢以前没有被描述.
研究的目的:
- 为了阐明Ralstonia eutropha H16用于l-ascorbate降解的新代谢途径.
- 识别和描述参与这种独特的代谢过程的基因和酶.
- 在其他细菌物种中调查这种途径的流行情况.
主要方法:
- 通过RNA测序 (RNaseq) 来识别候选基因.
- 序列相似性和基因组邻近网络分析以预测蛋白质功能.
- 用基因删除突变体进行体外酶测定和体内生长研究以确认路径功能.
主要成果:
- 确定了8个为l-ascorbate消化酶编码的候选基因.
- 发现了包括氧化,环开放,酸重组和NAD+依赖性脱碳化在内的新酶步骤.
- 在数百种细菌中证实了该途径的存在, 包括病原体如*Pseudomonas aeruginosa*和*Acinetobacter baumannii*.
结论:
- *Ralstonia eutropha* H16具有一个全新的 l-ascorbate 代谢途径.
- 这一途径涉及独特的酶变化,扩大已知微生物代谢的范围.
- 这种途径的广泛分布表明它具有重要的生态和潜在的生物技术意义.
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