ArcA overexpression induces fermentation and results in enhanced growth rates of E. coli.
ArcA overexpression induces fermentation and results in enhanced growth rates of E. coli.
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DOI：
10.1038/s41598-017-12144-6
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发表时间：
2017-09-19
影响因子：
4.6
通讯作者：
Williamson JR
中科院分区：
文献类型：
--
作者：
Basan M;Hui S;Williamson JR
在细菌、酵母和癌细胞等多种生物体中，氧气存在下的溢出代谢以快速生长的速度发生，在生物技术中蛋白质或代谢化合物的生产过程中起着重要作用。正如最近提出的那样，溢出代谢可以从蛋白质组分配的角度来理解，因为发酵产生能量的蛋白质组成本低于呼吸。在这里，我们证明了ArcA在有氧条件下的过表达，导致呼吸通路的下调和大肠杆菌糖酵解底物的生长速度加快，与醋酸盐排泄和碳吸收率增加相一致。这些结果表明，发酵使生长更快，并表明在许多糖酵解碳源上发酵不受碳吸收的限制。因此，这些发现很难与已经提出的关于溢出代谢起源和发酵和呼吸生长速率依赖的许多替代假设相一致，这些假设基于有限的呼吸能力或摄取速率和分解代谢途径的限制。相反，正如ArcA过表达菌株的滞后期增加所表明的那样，呼吸能量代谢可能与一般的准备反应有关，观察到生长速率降低，但在最大化稳态生长速率方面优势有限。
Overflow metabolism in the presence of oxygen occurs at fast growth rates in a wide range of organisms including bacteria, yeast and cancer cells and plays an important role in biotechnology during production of proteins or metabolic compounds. As recently suggested, overflow metabolism can be understood in terms of proteome allocation, since fermentation has lower proteome cost for energy production than respiration. Here, we demonstrate that ArcA overexpression in aerobic conditions, results in downregulation of respiratory pathways and enhanced growth rates on glycolytic substrates of E. coli, coinciding with acetate excretion and increased carbon uptake rates. These results suggest that fermentation enables faster growth and demonstrate that fermentation on many glycolytic carbon sources is not limited by carbon uptake. Hence, these findings are difficult to reconcile with many alternative hypotheses that have been proposed for the origin of overflow metabolism and the growth rate dependence of fermentation and respiration, which are based on limited capacity of respiration or limitations in uptake rates and catabolic pathways. Instead, as suggested by increased lag phases of ArcA overexpression strains, respiratory energy metabolism may be related to a general preparatory response, observed for decreasing growth rates, but with limited advantages for maximizing steady-state growth rate.
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DOI：
10.1128/genomea.01038-14
发表时间：
2014-10-16
期刊：
Genome announcements
影响因子：
--
作者：
Grenier F;Matteau D;Baby V;Rodrigue S
通讯作者：
Rodrigue S
DOI：
10.1073/pnas.0403064101
发表时间：
2004-09-07
影响因子：
11.1
作者：
Malpica, R;Franco, B;Georgellis, D
通讯作者：
Georgellis, D
影响因子：
9.9
作者：
Kotte O;Volkmer B;Radzikowski JL;Heinemann M
通讯作者：
Heinemann M
影响因子：
64.8
作者：
Basan M;Hui S;Okano H;Zhang Z;Shen Y;Williamson JR;Hwa T
通讯作者：
Hwa T
影响因子：
2.6
作者：
Ramseier, TM
通讯作者：
Ramseier, TM