geoscience.net logo
+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Stabilization of delta mu H+ in Escherichia coli upon K+ and Na+ transmembrane gradient dissipation


, : Stabilization of delta mu H+ in Escherichia coli upon K+ and Na+ transmembrane gradient dissipation. Biokhimiia 47(1): 137-144

The role of Na+/K+ gradients as a stabilizing factor for the energetics of bacterial cell has been evaluated. It was shown that in the presence of a Na+/K+ gradient across the membrane the cells of the unc mutant of E. coli retain their motility for some time under anaerobic conditions. This time coincides with that of dissipation of the K+ gradient by the bacteria during the anaerobiosis. A switch-off of the generator (respiration) entails a collapse of the membrane potential (delta psi). The anaerobiosis-induced efflux of K+ from the cells is uncoupler-stimulated, thus suggesting that the K+ efflux has an electrogenic nature and stabilizes delta psi. The use of valinomycin allowed to establish a correlation between the rate of K+ efflux, the delta psi value and the rate of bacterial motion under anaerobic conditions. After the onset of anaerobiosis the level of delta psi decreases faster as the concentration of extracellular K+ increases. It was shown that the capacity of the K+ gradient as te delta psi buffer depends on the pH of the medium and that artificial Na+ gradient can energize the E. coli cells by Na+/K+ exchange.

US$29.90

PMID: 7039692


Other references

Yokoji M.; Kawamura R.; Yokoyama M.; Okuno M.; Harada Y., 1991: Four cases of fluctuating perceptive deafness associated with behcets disease. Audiology Japan 34(5): 483-484

Huerta, R.; Jordano, R.; Medina, L.M.; López, C., 2004: Population dynamics of the constitutive biota of French dry sausages in a pilot-scale ripening chamber. The population dynamic of constitutive biota on 84 samples belonging to two different types of French fermented dry sausages during the ripening process in a pilot-scale ripening chamber was investigated. Samples were analyzed in three steps of th...

Aniołowska, M.; Kita, A., 2016: The effect of frying on glycidyl esters content in palm oil. The changes in palm oil, as affected by frying temperature, and content of the glycidyl esters (GEs) were studied. Potato chips were fried intermittently in palm oil, which was heated for 8 h daily over five consecutive days. Frying was conducted...

Yasuda, S.; Yasuda, T.; Hui, Y.; Liu, M-Yih.; Suiko, M.; Sakakibara, Y.; Liu, M-Cheh., 2009: Concerted action of the cytosolic sulfotransferase, SULT1A3, and catechol-O-methyltransferase in the metabolism of dopamine in SK-N-MC human neuroblastoma cells. Conjugation reactions catalyzed by the cytosolic sulfotransferase, SULT1A3, or catechol-O-methyltransferase (COMT) are known to be involved in the regulation and homeostasis of dopamine and other monoamine neurotransmitters. Whether different conj...

Qi, X.Q.; Newman, D.; Dorian, P., 1999: Azimilide decreases defibrillation voltage requirements and increases spatial organization during ventricular fibrillation. Drugs with class III antiarrhythmic properties generally decrease defibrillation threshold (DFT). However, the concentration effect relation for this effect and drug effects on ventricular fibrillation (VF) itself are not well understood. The obje...

Loedorff, C.J., 1967: Studies on the life-history and distribution in South Africa of Chironomus (Chironomus) transvaalensis Kieffer. Publications University Pretoria (NR). 1963-1964 ; 40: 87-88

Revich, L.R.; Grinspon, S.G.; Paredes, C.; Moreno, E.; Gené, R.; Jorge, M.A., 2002: Respiratory effects of halothane in a patient with refractory status asthmaticus. We describe the case of a 36 year old patient who was admitted to the intensive care unit (ICU) for an acute asthma attack that failed to respond to conventional treatment and required mechanical ventilation. The patient's condition improved...

Stang, S.; Kaifer, E.; Himmel, H-Jörg., 2014: Metal-free C-C coupling reactions with tetraguanidino-functionalized pyridines and light. Herein we report on metal-free C-C coupling reactions mediated by the pyridine derivative 2,3,6,7-tetrakis(tetramethylguanidino)pyridine under the action of visible light. The rate-determining step is the homolytic N-C bond cleavage of the initial...

Anonymous, 1960: How Far into the Future?. British Medical Journal 2(5201): 791-792

Kokes O., 1970: The white stork in the central flow of the elbe river up to 1964. Ziva 18(3): 112-113