Membrane potential under different growth conditions

Range (-140)-(-105) Table - link mV
Organism Bacteria Escherichia coli
Reference Tran QH, Unden G. Changes in the proton potential and the cellular energetics of Escherichia coli during growth by aerobic and anaerobic respiration or by fermentation. Eur J Biochem. 1998 Jan 15 251(1-2):538-43. p.541 table 2PubMed ID9492330
Comments P.541 note above table 2: "Proton potential of E. coli AN387 (EDTA treated cells) incubated with glycerol plus various electron acceptors or with glucose (fermentative conditions): For each condition the intracellular volume (Vin), the membrane potential (Δѱ) and ΔpH were determined in three or more independent experiments. Vin was measured as the difference from the [3H] H2O and the [14C]taurine space by silicone oil centrifugation. Δѱ was calculated from the accumulation of the [14C]Ph4P+ cation in EDTA-treated cells, ΔpH from the distribution of [14C]benzoate. For the calculation of Δѱ, the cytoplasmic concentrations of Ph4P+ ([Ph4P+in]) were taken (Δѱ=59 mV×lg[Ph4P+in]/[Ph4P+ex]). [Ph4P+in] was obtained by the method of Zaritzky et al. (1981) from the total Ph4P+ (Ph4P+cell, corresponding to cytoplasmic plus membrane-bound Ph4P+) accumulated by the bacteria (for details see text). [Ph4P+cell] was calculated from Ph4P+cell/Vin. dc, dry cells." (-140mV) for growth on (Glycerol + O2) substrate, (-105mV) for fermentative growth on Glucose. See BNID 102120, 104083
Entered by Uri M
ID 103386