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Updated: Jan 17, 2026

Characterizing Mediated Extracellular Electron Transfer in Lactic Acid Bacteria with a Three-Electrode, Two-Chamber Bioelectrochemical System

Characterizing Mediated Extracellular Electron Transfer in Lactic Acid Bacteria with a Three-Electrode, Two-Chamber Bioelectrochemical System

Published on: August 23, 2024

通过操纵Pyruvate脱酶复合物E2和乳酸脱酶复合物E2和乳酸脱酶来增强乳酸盐的生产,用于Lactococcus lactis的代谢工程

Xiaocui Zhang¹, Manuel Montalbán-López², Xingjiang Li¹

¹School of Food and Biological Engineering, Anhui Fermented Food Engineering Research Center, Key Laboratory for Agricultural Products Processing of Anhui Province, Hefei University of Technology, Hefei 230009, China.

Journal of agricultural and food chemistry

|September 24, 2025

概括

淘汰Lactococcus lactis中pyruvate脱酶复合体E2亚单元会影响新陈代谢,减少生物质和ATP,但增加NAD+/NADH比率和乳酸盐产量. 这为优化乳酸产量提供了洞察力.

科学领域:

微生物学微生物学
代谢工程是代谢工程.
生物化学生物化学

背景情况:

乳球球菌乳糖中的酸盐脱酶复合体 (PDHc) 对于将糖解与三碳酸 (TCA) 循环连接至关重要.
了解PDHc子单元的功能,特别是E2,对于代谢途径操纵至关重要.

研究的目的:

为了研究一个pyruvate脱酶复合物E2 (pdh E2) 淘汰的代谢后果在乳球菌乳糖.
探索调节pdh E2以提高乳酸生产的潜力.

主要方法:

构建和分析一个pdh E2淘汰菌株的乳球菌.
测量生物质,PDHc活性,ATP水平,NAD+/NADH比率和乳酸盐生产.
乳酸脱酶活性和基因转录水平的分析.

主要成果:

与野生类型相比,pdh E2淘汰菌株表现出减少的生物质 (76%),PDHc活性 (48%较低) 和ATP (13.4%较低).
在淘汰赛菌株中观察到NAD+/NADH比率显著增加 (1.5倍以上).
牛乳酸生产在淘汰赛 (5.6%) 和工程菌株中都增加,乳酸脱酶活性因尼诱导而增强.

结论:

该pdh E2亚单元在乳球菌乳糖代谢中起着重要作用,影响生物质,能源生产和氧化还原平衡.
调节pdh E2提供了一种可行的策略,用于增强Lactococcus lactis的乳酸盐生产.
对pdh E2功能的进一步研究可以提供对pyruvate代谢及其优化更深入的见解.

关键词:

乳球球菌 (lactococcus lactis) 是一种乳球菌.乳酸脱酶的使用方法乳糖生产乳糖生产皮鲁酸是一种酸盐.皮鲁酸盐脱酶的使用方法

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