title: Effects of antibiotics on the cation composition of Bifidobacterium bifidum subspecies pennsylvanicum.
abstract: Cell wall-inhibitory antibiotics caused a marked reduction of intracellular K+ and a small increase of Na+, together resulting in a decline of intracellular cation content. Chloramphenicol and tetracycline increased intracellular K+ but actinomycin decreased both Na+ and K+ content. The release and uptake of 86Rb+ were similarly affected by the antibiotics as the K+ content. The osmotic resistance of the protoplasts isolated from antibiotic-treated cells was apparently increased by inhibitors of cell wall synthesis, but decreased by inhibitors of protein synthesis. The ionophore valinomycin enhanced growth in normal and K+-rich medium, although cells released more than 90% of intracellular K+.
mesh_terms: D000191:Actinomycetaceae / Q000187:drug effects* / Q000502:physiology; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000096:biosynthesis; D002473:Cell Wall / Q000187:drug effects; D009996:Osmotic Fragility; D011188:Potassium / Q000378:metabolism*; D011523:Protoplasts / Q000502:physiology; D012413:Rubidium / Q000378:metabolism; D012964:Sodium / Q000378:metabolism*; D014634:Valinomycin / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D014634:Valinomycin; D012964:Sodium; D012413:Rubidium; D011188:Potassium