一个独特的cis-3-hydroxy-l-proline脱水酶在酶超级家族
Xinshuai Zhang1, Ritesh Kumar, Matthew W Vetting
1Departments of Biochemistry and Chemistry and ‡Institute for Genomic Biology, University of Illinois at Urbana-Champaign , Urbana, Illinois 61801, United States.
Journal of the American Chemical Society
|January 23, 2015
概括
研究人员在Labrenzia聚合物中发现了一种新型酶,可以将cis-3-hydroxy-l-proline (c3LHyp) 转化为可用的碳来源. 这一发现揭示了细菌中proline利用的新代谢途径.
科学领域:
- 生物化学 生物化学
- 微生物学 微生物学
- 酶学 是一种酶学.
背景情况:
- 酶超级家族包括具有多样化催化活动的酶.
- 乳糖酸乳化酶 (MLE) 亚组成员参与芳香化合物代谢.
- 在Labrenzia聚合物中,没有特征的MLE亚组成员的特定功能是未知的.
研究的目的:
- 来自Labrenzia聚合物的未经表征的MLE亚群酶 (A0NXQ8) 的功能.
- 为了研究L.聚合物的代谢能力,关于氧的利用.
- 为了探索A0NXQ8基因的基因组背景.
主要方法:
- 对基因的基因组位置的生物信息分析.
- 酶活性查使用proline类型的图书馆.
- 由酶A0NXQ8与cis-3-hydroxy-l-proline (c3LHyp) 催化反应的表征.
主要成果:
- 确定了属于MLE亚组的未表征的酶A0NXQ8.
- A0NXQ8在c3LHyp上表现出双重活性:2-表皮化和脱水.
- 这种酶作为cis-3-hydroxy-l-proline脱水酶 (c3LHyp脱水酶) 起作用.
- 基因组学背景表明,L. aggregata可以代谢各种氧异构体.
结论:
- 这项研究证实了A0NXQ8.8的新型c3LHyp脱水酶功能.
- 这些发现提供了使L. aggregata能够使用同位素基素作为碳来源的代谢途径的证据.
- 这扩大了我们对细菌代谢多样性和酶功能的理解.
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