对Physarum polycehalum三糖合成途径的分析
Rihito Morita1, Shohei Okano1, Atsushi Furukawa1
1Department of Bioscience, Faculty of Life Science, Okayama University of Science, 1-1 Ridai-cho, Kita-ku, Okayama, 700-0005, Japan.
Biochemical and biophysical research communications
|October 13, 2023
概括
菲萨鲁姆多头 (Physarum polycephalum) 在干燥耐受性方面积累了三糖. 在抗干旱的硬化物中,六酸酸酶 (T6pp) 表达显著增加,这表明它在生存中发挥了关键作用.
科学领域:
- 生物化学 生物化学
- 细胞生物学 细胞生物学
- 欧核生物分子生物学 欧核生物分子生物学
背景情况:
- 干旱对许多生物体来说构成了重大生存挑战.
- 真的粘液菌Physarum polycephalum通过形成硬化菌具有显著的干燥耐受性.
- 众所周知,三糖是一种分糖,在各种生物体的压力耐受性中起作用.
研究的目的:
- 研究Physarum polycephalum中干燥耐受性的机制,重点关注三糖代谢.
- 量化P. polycephalum.不同生命阶段的三糖含量.
- 识别和描述涉及干燥过程中三糖合成和降解的关键酶.
主要方法:
- 在植物性等离子体和干旱引起的硬化物中量化测量三糖含量.
- RNA测序 (RNAseq) 用于分析与三糖代谢相关的基因的表达.
- 在大肠杆菌中复合酶 (T6pp,Tps/Tpp,TreZ,Trey) 的克隆,表达和净化.
- 纯化重组酶的酶活性测定和动力分析 (迈凯利斯-门方程).
主要成果:
- 与等离子体相比,硬化体中的三糖含量大约是硬化体的473倍.
- 三糖6酸盐酸化酶 (T6pp) 的表达显著增加 (约. 15倍) 在硬化组织中.
- 重组T6pp,Trey和TreZ酶被证实是活跃的,并参与了三糖代谢.
- 虽然T6pp表达与干燥相关,但TreY和TreZ表达在生命阶段之间没有显著的变化.
结论:
- 六酸酸酶 (T6pp) 可能是一个关键的酶,有助于高积和干燥耐受性在Physarum polycephalum sclerotia.
- 在真核生物中首次发现的TreY和TreZ酶似乎不是这种生物体在干燥过程中对三糖激增的主要贡献者.
- 这项研究为真核生物三糖代谢和干燥生存策略提供了新的见解.
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