[H+-K+-exchange in anaerobically grown Escherichia coli bacteria during use of various sugars as exogenous energy sources]. / H+-K+-obmen u anaérobno vyrashchennykh bakterii Escherichia coli pri ispol'zovanii razlichnykh sakharov v kachestve ékzogennykh istochnikov énergii.

E.coli bacteria, grown in anaerobic conditions, in the medium with glucose, lactose or maltose, upon transferring into a fresh medium with the same sugar acidify it and accumulate potassium ions with a fixed stoichiometry for the N,N'-dicyclohexylcarbodiimide-inhibited cation fluxes, which is equal to 2H+ of the cytoplasm per one K+ of the medium. Such an H(+)-K(+)-exchange is sensitive to osmotic shock. In the medium with lactose or maltose cation fluxes are less and the intracellular K+ activity at the moment of maximal accumulation is lower. The H(+)-K(+)-exchange with a variable stoichiometry of cation fluxes is lost in bacteria, grown in a medium with lactose or maltose.

[K+-dependent enzyme activity of H+-ATPase in the E. coli membrane]. / K+-zavisimaia fermentativnaia aktivnost' H+-ATFazy membrany E. coli.

It was shown that DCCD-sensitive ATPase activity of isolated membranes and preparations of F1F0 only from anaerobically grown E. coli depended on K+ activity. F1F0 include two additional proteins which correspond to the Trk system. The data improve the possibility to form supercomplex (F1F0-Trk) functioning as the H(+)-K(+)-pump.

[N,N'-dicyclohexylcarbodiimide-sensitive K+-dependent H+ secretion from anaerobically grown E. coli cells]. / N,N'-ditsiklogeksilkarbodiimid-chuvstvitel'naia K+-zavisimaia sekretsiia H+ iz anaérobno vyrashchennykh kletok E. coli.

Dependence of N,N'-dicyclohexylcarbodiimide (DCC)-sensitive H+ secretion of K+ activity was discovered. This dependence took place only in anaerobically grown bacteria, and only at the structural intact DCC-sensitive H+-ATPase complex and K+-ionophore Trk.

[N,N'-dicyclohexylcarbodiimide-sensitive K+-dependent ATPase activity in Escherichia coli]. / Izuchenie N,N'-ditsiklogeksilkarbodiimid-chuvstvitel'noi K+-zavisimoi ATFaznoi aktivnosti u Escherichia coli.

ATPase activity sensitive to N,N'-dicyclohexylcarbodiimide and dependent on K+ content in medium is observed only in anaerobically grown Escherichia coli and as the analysis of mutants with defects in different subunits of (F0F1) H+-ATPase and in potassium transport shows only under the structural integrity of both F0F1 and K+-ionophore (the Trk system). The obtained results confirm the data on the H+/K+-exchange and indicate that the F0F1 and Trk systems in anaerobically grown bacteria unite into the same membrane supercomplex inside which the direct energy transfer occurs without a mediation of delta-mu H+.

[The capacity of anaerobically grown bacteria to exchange the 2H+ of the cell for the K+ of the medium and to maintain a high K+ distribution between cell and medium]. / Issledovanie sposobnosti anaérobno vyrashchennykh bakterii obmenivat' 2H+ kletki na K+ sredy i podderzhivat' vysokoe raspredelenie K+ mezhdu kletkoi i sredoi.

The N,N'-dicyclohexylcarbodiimide sensitive exchange of 2H+ of a cell for K+ of medium stable to pH, K+ activity and temperature changes has been discovered in anaerobically grown gram-negative Escherichia coli, Salmonella typhimurium. S. enteritidis, Proteus mirabilis, P. vulgaris, anaerobic gram-positive bacteria Streptococcus faecalis, Lactobacillus salivarius, L. lactis in the presence of exogenic energy source. This exchange in gram-negative bacteria is operating only at increase of medium osmolarity. The high K+ distribution between cell and medium has been reached during the exchange of 2H+ for one K+ and the corresponding potassium equilibrium potential is much more than the measured delta psi. In aerobically grown E. coli, S. typhimurium, Brevibacterium flavum and aerobic Micrococcus luteus exchange of 2H+ for K+ does not take place, the K+ distribution is lower and in good conformity with the measured delta psi. It is assumed that exchange of 2H+ for K+ in anaerobic bacteria is carried out by the H+-ATPase complex and the Trk (or Trk-like) system of K+ absorption united into the same membrane supercomplex which functions as the H+-K+-pump and supports the high K+ distribution between cell and medium.