Winkler H H
J Bacteriol. 1984 Jan;157(1):197-201. doi: 10.1128/jb.157.1.197-201.1984.
The potassium permeability of Rickettsia prowazekii was characterized by chemical measurement of the intracellular sodium and potassium pools and isotopic flux measurements with 86Rb+ as a tracer. R. prowazekii, in contrast to Escherichia coli, did not maintain a high potassium-to-sodium ratio in their cytoplasm except when the potassium-to-sodium ratio in the extracellular medium was high or when the extracellular concentrations of both cations were low (ca. 1 mM). Both influx and efflux assays with 86Rb+ demonstrated that the rickettsial membrane had limited permeability to potassium and that incorporation of valinomycin into these cells increased these fluxes at least 10-fold. The transport of potassium showed specificity and dependence on rickettsial metabolism. The increased flux of potassium which results from the incorporation of valinomycin into the rickettsial membrane was detrimental to both lysine transport and lysis of erythrocytes by the rickettsiae.
通过对细胞内钠和钾池进行化学测量以及以⁸⁶Rb⁺作为示踪剂进行同位素通量测量，对普氏立克次体的钾通透性进行了表征。与大肠杆菌不同，普氏立克次体在其细胞质中并未维持高钾钠比，除非细胞外培养基中的钾钠比很高，或者两种阳离子的细胞外浓度都很低（约1 mM）。用⁸⁶Rb⁺进行的流入和流出试验均表明，立克次体膜对钾的通透性有限，并且将缬氨霉素掺入这些细胞中可使这些通量至少增加10倍。钾的转运具有特异性并依赖于立克次体的代谢。将缬氨霉素掺入立克次体膜中导致的钾通量增加，对立克次体的赖氨酸转运和红细胞裂解均有害。
