Impact of membrane-associated hydrogenases on the FOF1-ATPase in Escherichia coli during glycerol and mixed carbon fermentation: ATPase activity and its inhibition by N,N′-dicyclohexylcarbodiimide in the mutants lacking hydrogenases

2015 ◽  
Vol 579 ◽  
pp. 67-72 ◽  
Author(s):  
Syuzanna Blbulyan ◽  
Armen Trchounian
Keyword(s):  
Escherichia Coli ◽  
Atpase Activity ◽  
Fof1 Atpase

External succinate and potassium ions influence Dcu dependent FOF1-ATPase activity and H+ flux of Escherichia coli at different pHs

2020 ◽  
Vol 52 (5) ◽  
pp. 377-382 ◽  
Author(s):  
G. Mikoyan ◽  
L. Karapetyan ◽  
A. Vassilian ◽  
A. Trchounian ◽  
K. Trchounian
Keyword(s):  
Escherichia Coli ◽  
Atpase Activity ◽  
Potassium Ions ◽  
Fof1 Atpase

scholarly journals Evidence for Escherichia coli DcuD carrier dependent FOF1-ATPase activity during fermentation of glycerol

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
L. Karapetyan ◽  
A. Valle ◽  
J. Bolivar ◽  
A. Trchounian ◽  
K. Trchounian
Keyword(s):  
Escherichia Coli ◽  
Atpase Activity ◽  
Fof1 Atpase

scholarly journals Dynamic regulation of extracellular ATP in Escherichia coli

2017 ◽  
Vol 474 (8) ◽  
pp. 1395-1416 ◽  
Author(s):  
Cora Lilia Alvarez ◽  
Gerardo Corradi ◽  
Natalia Lauri ◽  
Irene Marginedas-Freixa ◽  
María Florencia Leal Denis ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Atpase Activity ◽  
Atp Release ◽  
Membrane Vesicles ◽  
Fold Increase ◽  
Extracellular Atp ◽  
Outer Membrane Vesicles ◽  
Dynamic Regulation ◽  
E Coli

We studied the kinetics of extracellular ATP (ATPe) in Escherichia coli and their outer membrane vesicles (OMVs) stimulated with amphipatic peptides melittin (MEL) and mastoparan 7 (MST7). Real-time luminometry was used to measure ATPe kinetics, ATP release, and ATPase activity. The latter was also determined by following [32P]Pi released from [γ-32P]ATP. E. coli was studied alone, co-incubated with Caco-2 cells, or in rat jejunum segments. In E. coli, the addition of [γ-32P]ATP led to the uptake and subsequent hydrolysis of ATPe. Exposure to peptides caused an acute 3-fold (MST7) and 7-fold (MEL) increase in [ATPe]. In OMVs, ATPase activity increased linearly with [ATPe] (0.1–1 µM). Exposure to MST7 and MEL enhanced ATP release by 3–7 fold, with similar kinetics to that of bacteria. In Caco-2 cells, the addition of ATP to the apical domain led to a steep [ATPe] increase to a maximum, with subsequent ATPase activity. The addition of bacterial suspensions led to a 6–7 fold increase in [ATPe], followed by an acute decrease. In perfused jejunum segments, exposure to E. coli increased luminal ATP 2 fold. ATPe regulation of E. coli depends on the balance between ATPase activity and ATP release. This balance can be altered by OMVs, which display their own capacity to regulate ATPe. E. coli can activate ATP release from Caco-2 cells and intestinal segments, a response which in vivo might lead to intestinal release of ATP from the gut lumen.

scholarly journals Partial diploids of Escherichia coli carrying normal and mutant alleles affecting oxidative phosphorylation

1977 ◽  
Vol 162 (3) ◽  
pp. 665-670 ◽  
Author(s):  
F Gibson ◽  
G B Cox ◽  
J A Downie ◽  
J Radik
Keyword(s):  
Escherichia Coli ◽  
Fluorescence Quenching ◽  
Oxidative Phosphorylation ◽  
Atpase Activity ◽  
Adenosine Triphosphatase ◽  
Growth Yields ◽  
Normal Allele ◽  
Adenosine Triphosphatase Activity

A plasmid was isolated which included the region of the Escherichia coli chromosome carrying the known genes concerned with oxidative phosphorylation (unc genes). This plasmid was used to prepare partial diploids carrying normal unc alleles on the episome and one of the three mutant alleles (unc A401, uncB402 or unc-405) on the chromosome. These strains were compared with segregants from which the plasmid had been lost. Dominance of either normal ormutant unc alleles was determined by growth on succinate, growth yields on glucose, Mg-ATPase (Mg2+-stimulated adenosine triphosphatase) activity, atebrin-fluorescence quenching, ATP-dependent transhydrogenase activity and oxidative phosphorylation. In all the above tests, dominance of the normal allele was observed. However, in membranes from the diploid strains which carried a normal allele and either of the mutant alleles affecting Mg-ATPase activity (uncA401 or unc-405), the energy-linked functions were only partially restored.

scholarly journals Stand-alone ClpG disaggregase confers superior heat tolerance to bacteria

2017 ◽  
Vol 115 (2) ◽  
pp. E273-E282 ◽  
Author(s):  
Changhan Lee ◽  
Kamila B. Franke ◽  
Shady Mansour Kamal ◽  
Hyunhee Kim ◽  
Heinrich Lünsdorf ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Gene Transfer ◽  
Horizontal Gene Transfer ◽  
Atpase Activity ◽  
Stationary Phase ◽  
Virulence Factor ◽  
Heat Tolerance ◽  
Molecular Features ◽  
Partner Proteins

AAA+ disaggregases solubilize aggregated proteins and confer heat tolerance to cells. Their disaggregation activities crucially depend on partner proteins, which target the AAA+ disaggregases to protein aggregates while concurrently stimulating their ATPase activities. Here, we report on two potent ClpG disaggregase homologs acquired through horizontal gene transfer by the species Pseudomonas aeruginosa and subsequently abundant P. aeruginosa clone C. ClpG exhibits high, stand-alone disaggregation potential without involving any partner cooperation. Specific molecular features, including high basal ATPase activity, a unique aggregate binding domain, and almost exclusive expression in stationary phase distinguish ClpG from other AAA+ disaggregases. Consequently, ClpG largely contributes to heat tolerance of P. aeruginosa primarily in stationary phase and boosts heat resistance 100-fold when expressed in Escherichia coli. This qualifies ClpG as a potential persistence and virulence factor in P. aeruginosa.

Sign in / Sign up

Export Citation Format

Share Document