Extensive exometabolome analysis reveals extended overflow metabolism in various microorganisms.
Extensive exometabolome analysis reveals extended overflow metabolism in various microorganisms.
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DOI：
10.1186/1475-2859-11-122
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发表时间：
2012-09-11
影响因子：
6.4
通讯作者：
Noack S
中科院分区：
文献类型：
--
作者：
Paczia N;Nilgen A;Lehmann T;Gätgens J;Wiechert W;Noack S
酵母、细菌和哺乳动物细胞的溢流代谢是众所周知的。它通常发生在葡萄糖过量的条件下，其特征是排泄副产物，如乙醇，乙酸盐或乳酸盐。这一现象也被称为短期Crabtree效应，在过去的几十年里得到了广泛的研究，但其基本的调节机制和在代谢中的功能作用仍不清楚。在这里，我们提出了一个全面的定量和时间依赖性的分析大肠杆菌，谷氨酸棒杆菌，地衣芽孢杆菌，酿酒酵母在良好控制的生物反应器培养的外代谢组。最令人惊讶的是，在所有情况下，在培养基中发现了多种多样的中心代谢中间体和氨基酸，细胞外浓度在微摩尔范围内变化。不同的假设，这些意见制定和实验测试。因此，在分批生长过程中，培养基中的中间体必须来自被动或主动运输，这是由于一种称为“延长”溢流代谢的新现象。此外，我们提供了广泛的证据表明，这可能是一个共同的特点，所有微生物物种培养条件下的碳过量和非抑制碳吸收。反过来，这一发现对代谢物平衡有影响，特别是对细胞内代谢物定量和13 C-代谢通量分析。
Overflow metabolism is well known for yeast, bacteria and mammalian cells. It typically occurs under glucose excess conditions and is characterized by excretions of by-products such as ethanol, acetate or lactate. This phenomenon, also denoted the short-term Crabtree effect, has been extensively studied over the past few decades, however, its basic regulatory mechanism and functional role in metabolism is still unknown. Here we present a comprehensive quantitative and time-dependent analysis of the exometabolome of Escherichia coli, Corynebacterium glutamicum, Bacillus licheniformis, and Saccharomyces cerevisiae during well-controlled bioreactor cultivations. Most surprisingly, in all cases a great diversity of central metabolic intermediates and amino acids is found in the culture medium with extracellular concentrations varying in the micromolar range. Different hypotheses for these observations are formulated and experimentally tested. As a result, the intermediates in the culture medium during batch growth must originate from passive or active transportation due to a new phenomenon termed “extended” overflow metabolism. Moreover, we provide broad evidence that this could be a common feature of all microorganism species when cultivated under conditions of carbon excess and non-inhibited carbon uptake. In turn, this finding has consequences for metabolite balancing and, particularly, for intracellular metabolite quantification and 13C-metabolic flux analysis.
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影响因子：
7.4
作者：
Bolten, Christoph J.;Kiefer, Patrick;Wittmann, Christoph
通讯作者：
Wittmann, Christoph
影响因子：
5
作者：
Veit, Andrea;Polen, Tino;Wendisch, Volker F.
通讯作者：
Wendisch, Volker F.
影响因子：
4.4
作者：
Vemuri, G. N.;Altman, E.;Eiteman, M. A.
通讯作者：
Eiteman, M. A.
影响因子：
2.9
作者：
Schaub, Jochen;Schiesling, Carola;Dauner, Michael
通讯作者：
Dauner, Michael
影响因子：
--
作者：
Valgepea K;Adamberg K;Nahku R;Lahtvee PJ;Arike L;Vilu R
通讯作者：
Vilu R