细菌的RuBisCO类蛋白和光合作用RuBisCO之间的功能联系
Hiroki Ashida1, Yohtaro Saito, Chojiro Kojima
1Graduate School of Biological Sciences, Nara Institute of Science and Technology (NAIST), 8916-5 Takayama, Ikoma, Nara 630-0101, Japan.
概括
来自Bacillus subtilis的细菌核糖二酸碳氧化酶/类似氧化酶的蛋白质 (RLP) 促进了 metionin 挽救途径. 来自Rhodospirillum rubrum的光合作用RuBisCO可以在功能上取代B. subtilis RLP,突出显示保存的酶能力.
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:
- 非光合作用细菌和Archaea拥有与 рибо二酸二氧化酶/氧化酶 (RuBisCO) 相同的基因.
- 在 Bacillus subtilis 中的一种 RuBisCO 样蛋白 (RLP) 具有未表征的功能.
研究的目的:
- 为了研究B. subtilis的RuBisCO样蛋白 (RLP) 的酶活性.
- 为了确定光合作用RuBisCO是否可以在氨酸救援途径中功能性取代B. subtilis RLP.
主要方法:
- 在B. subtilis RLP.上进行了酶活性测试.
- 一个B. subtilis突变,具有被破坏的RLP基因被创造出来.
- 这种突变被补充了来自Rhodospirillum rubrum的RuBisCO基因.
主要成果:
- 鉴定出 B. subtilis RLP 是催化 2,3-diketo-5-methylthiopentyl-1-phosphate 乙醇酶反应的.
- 反应发生在 metionin 救援途径内.
- 来自R. rubrum的光合作用RuBisCO挽救了B. subtilisRLP突变的生长缺陷.
结论:
- B. subtilis RLP 在氨酸救援途径中起着至关重要的作用.
- 光合作用RuBisCO保留了细菌氨酸救援途径中的功能活性,在各种生物体中展示了保存的酶功能.
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