Uncoupler resistance in E. coli Tuv and Cuv is due to the exclusion of uncoupler by the outer membrane.

  title={Uncoupler resistance in E. coli Tuv and Cuv is due to the exclusion of uncoupler by the outer membrane.},
  author={Robert S. Haworth and Peter Ruhdal Jensen and Ole Michelsen and John A. Wyatt and Clive J. Brealey and R. Brian Beechey},
  journal={Biochimica et biophysica acta},
  volume={1019 1},
The uncoupler resistant bacterial strains E. coli Tuv and Cuv share the high deoxycholate sensitivity of the parent strain, Doc S. However, both Tuv and Cuv show greater resistance than Doc S to other detergents. Measurement of the periplasmic volume indicates that the outer membrane of Doc S is freely permeable to both TPP+ and hydroxymethylinulin. Tuv and Cuv are able to exclude these compounds. EDTA treatment was necessary prior to measuring membrane potential in Tuv and Cuv. Under… 
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Differential permeability for lipophilic compounds in uncoupler-resistant cells of Escherichia coli.
It is concluded that lipophilic materials must permeate the outer membrane of E. coli by at least two different routes, however, uncoupler-resistance in UR-3 appears to be more complex than the provision of an outer membrane barrier to uncouplers.
Protonophore-resistance and cytochrome expression in mutant strains of the facultative alkaliphile Bacillus firmus OF4.
Two protonophore-resistant mutants of the facultative alkaliphile Bacillus firmus OF4 811M maintained a higher delta mu H+ and a correspondingly higher delta Gp than the parent strain when growing in sublethal concentrations of CCCP, apparently as a result of mutational changes affecting respiratory chain composition.
Isolation of Tn917 insertional mutants of Bacillus subtilis that are resistant to the protonophore carbonyl cyanide m-chlorophenylhydrazone.
Transposition libraries prepared from Bacillus subtilis were screened for mutants that had insertions in the chromosome resulting in resistance to the protonophore carbonylcyanide m-chlorophenylhydrazone (CCCP), and three of these strains were found to have distinct insertion sites that resulted in changes in fatty acid composition of the membrane lipids.
A protet-based, protonic charge transfer model of energy coupling in oxidative and photosynthetic phosphorylation.
  • D. Kell
  • Medicine, Chemistry
    Advances in microbial physiology
  • 2021
A protet-based model can account for all the necessary observations, including all of those inconsistent with chemiosmotic coupling, and provides for a variety of testable hypotheses by which it might be refined.
Expression de protéines dans des bactéries gram négatif, avec un rapport du volume périplasmique au volume cytoplasmique compris entre 0,5:1 et 10:1
L'invention concerne des bacteries Gram negatif modifiees ayant un volume periplasmique accru. L'invention concerne egalement des procedes d'expression de genes exogenes dans les bacteries et de


Uncoupler resistance in Escherichia coli: the role of cellular respiration.
It is suggested that the active resistance of strain TUV results from the exclusion of uncoupler by the interaction of inner and outer membrane components in a manner modulated by the degree of cellular energization.
Escherichia coli mutants resistant to uncouplers of oxidative phosphorylation.
Two mutant strains of E. coli resistant to the uncoupling agents 4,5,6,7- tetrachloro-2-trifluoromethyl benzimidazole and carbonyl cyanide m-cblorophenylhydrazone were isolated and it is concluded that uncoupler resistance in these strains has arisen as a consequence of mutations which directly affect a specific site of unc Coupler action within the cytoplasmic membrane.
Effect of uncouplers on the bioenergetic properties of a carbonyl cyanide m-chlorophenylhydrazone-resistant mutant Escherichia Coli UV6
The effects of carbonyl cyanide m-chlorophenylhydrazone (CCCP) and tri-n-butyltin chloride (Bu3SnCl) on proline transport, proton uptake and the transmembrane pH gradient in intact cells have been
Membrane bioenergetic parameters in uncoupler-resistant mutants of Bacillus megaterium.
The retention of malate-driven ATP synthesis in the absence of a significant pH gradient or electrical potential suggests that an alternative intermediate is involved in coupling oxidation to phosphorylation.
Isolation and characterization of uncoupler-resistant mutants of Bacillus subtilis
Correlations between protonophore resistance and the membrane lipid compositions of the wild type, mutants, and revertants were most consistent with the hypothesis that a reduction in the content of monounsaturated C16 fatty acids in the membrane phospholipids is related to the ability to synthesize ATP at low bulk transmembrane electrochemical gradients of protons.
Periplasmic space in Salmonella typhimurium and Escherichia coli.
The volume of the periplasmic space in Escherichia coli and Salmonella typhimurium cells was measured, and it was shown that there is a Donnan equilibrium between theperiplasm and the extracellular fluid, and that the perplasm and cytoplasm are isoosmotic.
Oxidative phosphorylation by isolated membrane vesicles from Bacillus megaterium and its uncoupler-resistant mutant derivative.
The results indicate that the characteristic bioenergetic properties exhibited by whole cells of C8 are retained in a vesicle system and thus cannot be attributed to a cytoplasmic, substrate level activity.
The protonophore resistance of Bacillus megaterium is correlated with elevated ratios of saturated to unsaturated fatty acids in membrane phospholipids.
The experiments here support the hypothesis developed from work with Bacillus subtilis that changes in the fatty acid composition of the membrane phospholipids affect energy coupling, and make it clear that simple increases or decreases in the hydrolytic activity of ATPase in the uncoupler-resistant mutants of bacilli are not correlated with resistance in some direct way.
Electron spin resonance studies of lipid fluidity changes in membranes of an uncoupler-resistant mutant of Escherichia coli.
The fluidity of the lipids in membrane preparations from a mutant of Escherichia coli resistant to the uncoupler CCCP, grown at different temperatures with and without CCCP, was examined by electron
Quantitative analysis of proton-linked transport systems. The lactose permease of Escherichia coli.
It is concluded that the concentration of lactose within the cell is governed by kinetic factors rather than pH-dependent changes in the proton/substrate stoicheiometry.