Homeostasis of metabolites in Escherichia coli on transition from anaerobic to aerobic conditions and the transient secretion of pyruvate.
Homeostasis of metabolites in Escherichia coli on transition from anaerobic to aerobic conditions and the transient secretion of pyruvate.
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DOI：
10.1098/rsos.160187
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发表时间：
2016-08
影响因子：
3.5
通讯作者：
Williamson MP
中科院分区：
文献类型：
--
作者：
Yasid NA;Rolfe MD;Green J;Williamson MP
我们建立了一种快速猝灭从大肠杆菌恒定培养物中提取的样品的方法，该方法可以用1H核磁共振重复性和可靠性地测量细胞外和细胞内的代谢物，并应用于研究从厌氧生长到有氧生长过程中的主要中心代谢物。几乎所有的代谢物在空气扰动后都表现出逐渐的变化，这与立即抑制丙酮酸甲酸裂解酶、稀释溢出的代谢物和诱导好氧酶是一致的。令人惊讶的是，尽管丙酮酸在细胞内的浓度几乎没有变化，但细胞外的浓度瞬间增加。细胞内没有丙酮酸的积累表明，一个或多个糖酵解酶可能重新定位到细胞膜上。为了验证这一假说，我们对染色体丙酮酸激酶(PykF)进行了修饰，使其能够表达PykF-绿色荧光蛋白或PykF-FLAG融合蛋白。测量表明，在曝气后5 分钟内，PYKF-FLAG重新定位到细胞膜上，然后缓慢地返回细胞质，这表明在曝气时，PYKF与细胞膜结合，促进丙酮酸的分泌，以维持细胞内恒定的水平。
We have developed a method for rapid quenching of samples taken from chemostat cultures of Escherichia coli that gives reproducible and reliable measurements of extracellular and intracellular metabolites by 1H NMR and have applied it to study the major central metabolites during the transition from anaerobic to aerobic growth. Almost all metabolites showed a gradual change after perturbation with air, consistent with immediate inhibition of pyruvate formate-lyase, dilution of overflow metabolites and induction of aerobic enzymes. Surprisingly, although pyruvate showed almost no change in intracellular concentration, the extracellular concentration transiently increased. The absence of intracellular accumulation of pyruvate suggested that one or more glycolytic enzymes might relocate to the cell membrane. To test this hypothesis, chromosomal pyruvate kinase (pykF) was modified to express either PykF-green fluorescent protein or PykF-FLAG fusion proteins. Measurements showed that PykF-FLAG relocates to the cell membrane within 5 min of aeration and then slowly returns to the cytoplasm, suggesting that on aeration, PykF associates with the membrane to facilitate secretion of pyruvate to maintain constant intracellular levels.
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影响因子：
5.2
作者：
Ederer M;Steinsiek S;Stagge S;Rolfe MD;Ter Beek A;Knies D;Teixeira de Mattos MJ;Sauter T;Green J;Poole RK;Bettenbrock K;Sawodny O
通讯作者：
Sawodny O
影响因子：
7.4
作者：
Bolten, Christoph J.;Kiefer, Patrick;Wittmann, Christoph
通讯作者：
Wittmann, Christoph
DOI：
10.1016/s1389-0344(02)00003-5
发表时间：
2002-06-01
期刊：
BIOMOLECULAR ENGINEERING
影响因子：
--
作者：
Buchholz, A;Hurlebaus, J;Takors, R
通讯作者：
Takors, R
影响因子：
5.7
作者：
MATTEVI, A;VALENTINI, G;CODA, A
通讯作者：
CODA, A
影响因子：
11.6
作者：
Graham, James W. A.;Williams, Thomas C. R.;Sweetlove, Lee J.
通讯作者：
Sweetlove, Lee J.