Proton conductance and regulation of proton/potassium fluxes in Escherichia coli FhlA-lacking cells during fermentation of mixed carbon sources.

Escherichia coli uptake potassium ions with the coupling of proton efflux and energy utilization via proton FF-ATPase. In this study contribution of formate hydrogen lyase (FHL) complexes in the proton/potassium fluxes and the formation of proton conductance (CH) were investigated using fhlA mutant strain. The proton flux rate (J) decreased in fhlA by ∼ 25 % and ∼70 % during the utilization of glucose and glycerol, respectively, at 20 h suggesting H transport via or through FHL complexes.

Regulation of metabolism and proton motive force generation during mixed carbon fermentation by an Escherichia coli strain lacking the FF-ATPase.

Proton FF-ATPase is the key enzyme in E. coli under fermentative conditions. In this study the role of E.

Propionic and valproic acids have an impact on bacteria viability, proton flux and ATPase activity.

Short-chain fatty acids like propionic (PPA) and valproic acids (VP) can alter gut microbiota, which is suggested to play a role in development of autism spectrum disorders (ASD). In this study we investigated the role of various concentrations of PPA and VP in gut enteric gram-negative Escherichia coli K12 and gram-positive Enterococcus hirae ATCC 9790 bacteria growth properties, ATPase activity and proton flux. The specific growth rate (µ) was 0.

Metabolic pathways and ΔpH regulation in Escherichia coli during the fermentation of glucose and glycerol in the presence of formate at pH 6.5: the role of FhlA transcriptional activator.

Escherichia coli is able to ferment mixed carbon sources and produce various fermentation end-products. In this study, the function of FhlA protein in the specific growth rate (µ), metabolism, regulation of ΔpH and proton ATPase activity was investigated. Reduced µ in fhlA mutant of ∼25% was shown, suggesting the role of FhlA in the growth process.

The role of Escherichia coli FhlA transcriptional activator in generation of proton motive force and F F -ATPase activity at pH 7.5.

Escherichia coli is able to utilize the mixture of carbon sources and produce molecular hydrogen (H ) via formate hydrogen lyase (FHL) complexes. In current work role of transcriptional activator of formate regulon FhlA in generation of fermentation end products and proton motive force, N'N'-dicyclohexylcarbodiimide (DCCD)-sensitive ATPase activity at 20 and 72 hr growth during utilization of mixture of glucose, glycerol, and formate were investigated. It was shown that in fhlA mutant specific growth rate was ~1.

Formate and potassium ions affect Escherichia coli proton ATPase activity at low pH during mixed carbon fermentation.

Escherichia coli is able to ferment not only single but also mixtures of carbon sources. The formate metabolism and effect of formate on various enzymes have been extensively studied during sole glucose but not mixed carbon sources utilization. It was revealed that in membrane vesicles (MV) of wild type cells grown at pH 7.

Understanding the Role of Escherichia coli Hydrogenases and Formate Dehydrogenases in the F F -ATPase Activity during the Mixed Acid Fermentation of Mixture of Carbon Sources.

During fermentation Escherichia coli produces di-hydrogen (H ) via reversible membrane-bound [Ni-Fe]-hydrogenases (Hyd). This study describes the total and N,N'-dicyclohexylcarbodiimide (DCCD) inhibited ATPase activity and H production at various pHs in E. coli wild type and mutants encoding Hyd enzymes and formate dehydrogenases (FDH) on fermentation of glucose, glycerol, and formate.