Alterations of glucose metabolism in Escherichia coli mutants defective in respiratory-chain enzymes

Kihira, Chie; Hayashi, Yasumasa; Azuma, Nagao; Noda, Sakiko; Maeda, Soya; Fukiya, Satoru; Wada, Masaaki; Matsushita, Kazunobu; Yokota, Atsushi

doi:10.1016/j.jbiotec.2011.06.029

Cited by 14 publications

(9 citation statements)

References 23 publications

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“…Under aerobic conditions, the picture was not that distinct, some TCA cycle genes showed higher and some lower expression than in the wild-type strain. An about two-fold enhanced activity of NDH-II in a NDH-I deletion strain under aerobic conditions has already been shown in batch cultures [58], fitting to the doubled expression level of ndh measured here. Some of the differences between the wild-type strain and the NDH I deletion strain under microaerobic conditions could result from the reduced activity of ArcA, like lower acetate formation rate and enhanced transcription of cytochrome oxidase bo (ArcA repressed) as well as decreased expression of cytochrome oxidase bd-I and bd-II (activated by ArcA).…”

Section: Discussionsupporting

confidence: 86%

Analysis of Escherichia coli Mutants with a Linear Respiratory Chain

2014

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The respiratory chain of E. coli is branched to allow the cells' flexibility to deal with changing environmental conditions. It consists of the NADH:ubiquinone oxidoreductases NADH dehydrogenase I and II, as well as of three terminal oxidases. They differ with respect to energetic efficiency (proton translocation) and their affinity to the different quinone/quinol species and oxygen. In order to analyze the advantages of the branched electron transport chain over a linear one and to assess how usage of the different terminal oxidases determines growth behavior at varying oxygen concentrations, a set of isogenic mutant strains was created, which lack NADH dehydrogenase I as well as two of the terminal oxidases, resulting in strains with a linear respiratory chain. These strains were analyzed in glucose-limited chemostat experiments with defined oxygen supply, adjusting aerobic, anaerobic and different microaerobic conditions. In contrast to the wild-type strain MG1655, the mutant strains produced acetate even under aerobic conditions. Strain TBE032, lacking NADH dehydrogenase I and expressing cytochrome bd-II as sole terminal oxidase, showed the highest acetate formation rate under aerobic conditions. This supports the idea that cytochrome bd-II terminal oxidase is not able to catalyze the efficient oxidation of the quinol pool at higher oxygen conditions, but is functioning mainly under limiting oxygen conditions. Phosphorylation of ArcA, the regulator of the two-component system ArcBA, besides Fnr the main transcription factor for the response towards different oxygen concentrations, was studied. Its phosphorylation pattern was changed in the mutant strains. Dephosphorylation and therefore inactivation of ArcA started at lower aerobiosis levels than in the wild-type strain. Notably, not only the micro- and aerobic metabolism was affected by the mutations, but also the anaerobic metabolism, where the respiratory chain should not be important.

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Section: Discussionsupporting

confidence: 86%

Analysis of Escherichia coli Mutants with a Linear Respiratory Chain

2014

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“…Thus, in the NDH‐1‐deficient mutant, protons needed for energy generation, which may have been produced by NDH‐1, may be derived from terminal oxidases, and probably result in high NADH consumption at the electron entry site of the respiratory chain. However, intriguingly, the NADH:NAD + ratio in these NDH‐1‐deficient mutants was increased significantly, in accordance with a previous report on an NDH‐1‐deficient E. coli mutant . Accompanying the high NADH level, we also observed a decrease in succinate formation and an increase in acetate formation, as was observed in the E. coli mutant, probably due to inhibition of the tricarboxylic acid cycle by NADH and the compensatory generation of ATP via the acetate pathway .…”

Section: Discussionsupporting

confidence: 92%

“…Thus, in addition to ATP generation, one function of the respiratory chain is to adjust the intracellular redox status and thereby control overall cellular metabolism . In Escherichia coli , inactivating NQOs increases the level of intracellular NADH and alters fermentation profiles, as exemplified by increased lactic acid and poly (3‐hydroxybutyrate) production . In Zymomonas mobilis , cell growth and ethanol production are also promoted by inactivating NQO .…”

Section: Introductionmentioning

confidence: 99%

Inactivating NADH:quinone oxidoreductases affects the growth and metabolism of Klebsiella pneumoniae

Zhang

Bao

Wei

et al. 2018

Biotech and App Biochem

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NADH:quinone oxidoreductases (NQOs) act as the electron entry sites in bacterial respiration and oxidize intracellular NADH that is essential for the synthesis of numerous molecules. Klebsiella pneumoniae contains three NQOs (NDH-1, NDH-2, and NQR). The effects of inactivating these NQOs, separately and together, on cell metabolism were investigated under different culture conditions. Defective growth was evident in NDH-1-NDH-2 double and NDH-1-NDH-2-NQR triple deficient mutants, which was probably due to damage to the respiratory chain. The results also showed that K. pneumoniae can flexibly use NQOs to maintain normal growth in single NQO-deficient mutants. And more interestingly, under aerobic conditions, inactivating NDH-1 resulted in a high intracellular NADH:NAD ratio, which was proven to be beneficial for 2,3-butanediol production. Compared with the parent strain, 2,3-butanediol production by the NDH-1-deficient mutant was increased by 46% and 62% in glycerol- and glucose-based media, respectively. Thus, our findings provide a practical strategy for metabolic engineering of respiratory chains to promote the biosynthesis of 2,3-butanediol in K. pneumoniae.

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“…These results indicate that the respiratory ATP generated by mitochondria is critical to confer butanol tolerance upon S. cerevisiae . Conversely, mutant E. coli strains lacking respiratory chain enzymes exhibit accelerated generation of glycolytic ATP and enhanced production of pyruvic and acetic acids [ 59 ] (Fig. 3 ).…”

Section: Introductionmentioning

confidence: 99%

ATP regulation in bioproduction

Hara

Kondo

2015

Microb Cell Fact

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Adenosine-5′-triphosphate (ATP) is consumed as a biological energy source by many intracellular reactions. Thus, the intracellular ATP supply is required to maintain cellular homeostasis. The dependence on the intracellular ATP supply is a critical factor in bioproduction by cell factories. Recent studies have shown that changing the ATP supply is critical for improving product yields. In this review, we summarize the recent challenges faced by researchers engaged in the development of engineered cell factories, including the maintenance of a large ATP supply and the production of cell factories. The strategies used to enhance ATP supply are categorized as follows: addition of energy substrates, controlling pH, metabolic engineering of ATP-generating or ATP-consuming pathways, and controlling reactions of the respiratory chain. An enhanced ATP supply generated using these strategies improves target production through increases in resource uptake, cell growth, biosynthesis, export of products, and tolerance to toxic compounds.

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Alterations of glucose metabolism in Escherichia coli mutants defective in respiratory-chain enzymes

Cited by 14 publications

References 23 publications

Analysis of Escherichia coli Mutants with a Linear Respiratory Chain

Analysis of Escherichia coli Mutants with a Linear Respiratory Chain

Inactivating NADH:quinone oxidoreductases affects the growth and metabolism of Klebsiella pneumoniae

ATP regulation in bioproduction

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