Control of sodium fluxes in Mycoplasma gallisepticum.
Swelling of Mycoplasma gallisepticum cells when incubated in a glucose-free isoosmotic NaCl buffer was shown to be due to the entrance of NaCl into the cell. Volume regulation therefore depends on Na+ extrusion. The mechanism of Na+ extrusion in cells and proteoliposomes, prepared from M. gallisepticum membrane fragments, was investigated by following both 22Na+ efflux and pH changes. Our results indicate that Na+ is expelled from cells via two separate mechanisms, an Na+/cation exchange mechanism and an Na+-ATPase. The possible association of these mechanisms with K+ accumulation is suggested.
Shirvan
M H
MH
Department of Membrane and Ultrastructure Research, Hebrew University-Hadassah Medical School, Jerusalem, Israel.
Schuldiner
S
S
Rottem
S
S
D001426:Bacterial Proteins / Q000378:metabolism; D001693:Biological Transport, Active / Q000187:drug effects; D002352:Carrier Proteins / Q000378:metabolism; D002414:Cations, Monovalent / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008564:Membrane Potentials; D009174:Mycoplasma / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism*; D012965:Sodium Chloride / Q000378:metabolism; D017923:Sodium-Hydrogen Exchangers; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors / Q000378:metabolism; D014475:Uncoupling Agents / Q000494:pharmacology
D001426:Bacterial Proteins; D002352:Carrier Proteins; D002414:Cations, Monovalent; D017923:Sodium-Hydrogen Exchangers; D014475:Uncoupling Agents; D012965:Sodium Chloride; D012964:Sodium; D000254:Sodium-Potassium-Exchanging ATPase