title: Induction of potassium efflux by cupric ions in Pseudomonas syringae ATCC 12271 and its correlation with cell viability.
abstract: In Pseudomonas syringae, Cu2+ induce a significant loss of K+ from the cells. The course of the efflux followed an approximately sigmoidal pattern. The maximum rate of K+ efflux, the time needed to achieve this rate and the maximum amount of K+ released from the cells, were dependent on copper concentration. Pre-treatment with several divalent cations modified markedly the parameters of potassium efflux induced by copper, by increasing the maximum rate of K+ efflux and the amount of K+ released after 4 min of copper treatment, and decreasing the time required to achieve the maximum rate. The addition of copper to cell suspensions resulted in a progressive decrease in the number of viable cells. Pre-treatment with Mg2+ or Ca2+ resulted in a decrease in the lethality of copper ions.
authors.affiliation: Centro de Citologia Experimental da Universidade do Porto, Portugal.
authors.forename: J P
authors.initials: JP
authors.lastname: Cabral
mesh_terms: D002118:Calcium / Q000494:pharmacology; D003300:Copper / Q000494:pharmacology*; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology; D011188:Potassium / Q000378:metabolism*; D011549:Pseudomonas / Q000187:drug effects / Q000378:metabolism*
chemical_list: D003300:Copper; D008274:Magnesium; D011188:Potassium; D002118:Calcium