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Daven B Khana^1,2, Annie Jen³, Evgenia Shishkova^3,4

¹Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, USA.

|September 16, 2025

概括

具有更强的热力学代谢途径需要更少的酶蛋白来维持细胞流动. 这项研究量化了细菌糖解路径的酶需求,揭示了热力学上有利的路径显著节省蛋白质.

科学领域:

代谢工程是代谢工程.
系统生物学系统生物学
生物化学生物化学

背景情况:

细胞必须平衡能源生产和生物合成与资源分配,包括酶合成和维护.
代谢途径在热力学优势上有所不同,影响细胞资源需求.
了解酶投资对于优化代谢流和细胞效率至关重要.

研究的目的:

为了测试一种假设,即热力学受约束的通路对细胞施加更大的蛋白质需求.
量化绝对糖溶酶度,并将其与代谢流和热力学驱动力联系起来.
为了比较不同细菌糖解路径的酶投资.

主要方法:

在 *Zymomonas mobilis*, *Escherichia coli* 和 *Clostridium thermocellum* 中量化绝对的糖分酶度.
酶度数据与*in vivo*代谢流程的整合.
测量热力学驱动力 (ΔG) 在糖解路径内的反应.

主要成果:

在 *Z. mobilis* 中,热力学上有利的恩特纳-杜多洛夫通路需要比 *C. thermocellum* 中受约束的依赖于酸盐的通路少75%的蛋白质,用于相同的流量.
早期路径反应具有更强的热力学有利性,通常需要较低的酶投资.
不可逆转的乙醇发酵途径所需的蛋白质投资比同等流量的可逆转途径要少.

结论:

蛋白质在糖解路径上的投资直接反映了它们的热力学有利性.
在热力学上有利的路径显著减少了给定代谢流量的酶资源需求.
研究结果为优化代谢工程策略提供了见解,以尽量减少蛋白质成本,同时最大限度地提高流量.

关键词:

亚维布里奥热细胞的活性克洛斯特里热细胞 (Clostridium thermocellum) 是一种热细胞.齐莫莫纳斯的移动性酶负荷是指酶负荷是指酶负荷.酶的度是酶的度.葡萄糖溶解是什么代谢流量是指代谢的流量.蛋白质组学蛋白质组学热力学热力学热力学

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