一个euryarchaeal lysyl-tRNA合成酶:与I类合成酶相似
1Department of Molecular Biophysics and Biochemistry, Yale University, Post Office Box 208114, 266 Whitney Avenue, New Haven, CT 06520-8114, USA.
Science (New York, N.Y.)
|November 14, 1997
概括
在Methanococcus maripaludis中发现了一种新型的lysyl转移RNA (tRNA) 合成酶 (LysRS),挑战了Euryarchaea中这种必需酶的假定缺席. 这种独特的LysRS属于I类,与以前已知的II类酶不同.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 考古基因组学 考古基因组学
背景情况:
- 欧亚古生物的基因组缺乏用于 lysyl转移RNA (tRNA) 合成酶 (LysRS) 的基因.
- 在生命的各个领域,lysRS对蛋白质合成至关重要.
- 以前的理解表明,LysRS在Euryarchaea中不存在.
研究的目的:
- 为了调查LysRS在Euryarchaea中的存在和性质.
- 在Methanococcus maripaludis中发现的一种新型LysRS的特征.
- 重新评估跨生命形式的氨基酸-tRNA合成酶的分类.
主要方法:
- 来自Methanococcus maripaludis的蛋白质净化.
- 基因克隆和测序. 基因克隆和测序.
- 氨基酸序列分析和图案识别.
- 酶活性测定. 酶活性测定.
主要成果:
- 从M. maripaludis净化了一种具有正规LysRS活性的62千多顿蛋白质.
- M. maripaludis LysRS 基因序列与已知来自其他领域的 LysRS 蛋白无关.
- 序列分析显示,LysRS属于I类,其特征是罗斯曼二核酸结合基因.
- 在其他Euryarchaea中发现了同类的未分配的开放阅读框架.
结论:
- 玛里帕卢迪斯甲球菌具有独特的I类LysRS,挑战其在Euryarchaea的假定缺席.
- 这一发现需要对LysRS分类和进化理解进行修订.
- 这一发现质疑了氨基酸-tRNA合成酶分类系统的普遍性.
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