证据表明,在古阿纪时代存在着复杂的酶复合体
Bernd Reisinger1, Josef Sperl, Alexandra Holinski
1Institute of Biophysics and Physical Biochemistry, University of Regensburg , Universitätsstraße 31, D-93053 Regensburg, Germany.
Journal of the American Chemical Society
|December 25, 2013
概括
研究人员从最后一个普遍共同祖先 (LUCA) 中重建了循环酶子单元 (HisF). 这种古老的酶具有很高的稳定性和催化活性,这表明数十亿年前存在复杂的酶功能.
科学领域:
- 生物化学 生物化学
- 进化生物学 进化生物学
- 结构生物学 结构生物学
背景情况:
- 大分子化石不存在,这限制了对已灭绝物种酶的知识.
- 伊米达糖酸盐合成酶 (ImGP-S) 复合体在代谢途径中至关重要.
研究的目的:
- 从最后一个普遍共同祖先 (LUCA) 中重建的ImGP-S的循环酶子单元 (HisF) 的特征.
- 了解古代酶的结构和功能特性及其进化起源.
主要方法:
- LUCA-HisF的晶体结构的确定.
- 生物化学测试以评估催化活性和热稳定性.
- 复杂的形成研究与现存和重建的HisH子单元.
主要成果:
- LUCA-HisF具有古老的 (βα) 8-桶折叠,类似于现存的HisF蛋白质.
- 该酶具有热稳定性,具有较高的催化活性,并与HisH.形成功能复合体.
- LUCA-HisF强烈地与重建的 LUCA-HisH 蛋白质结合.
结论:
- 高效的酶和复合物,包括基质通道和全osteric通信,存在于LUCA时代 (3.5亿年前).
- 酶进化可能比以前认为的要早得多.
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