title: Studies on the ionophorous antibiotics. XV The monovalent cation selective ionophorous activities of carriomycin, lonomycin and etheromycin.
abstract: The cations selectivity profiles of the carboxylic ionophores, carriomycin, lonomycin and etheromycin, have been investigated by measuring the complexation affinities for metal cations and the cation transport activity through an organic barrier. In a two-phase partition study, carriomycin and lonomycin formed complexes more readily with K+ than with NH4+, Rb+ or Na+, but not with Li+ or Cs+. On the other hand, etheromycin exhibited a great preference for K+ or NH4+ over Na+, Li+ or Rb+, but displayed no binding affinity for Cs+. The alklaine degradation product of lonomycin exhibited a preference for K+ or Na+, but its complexation affinities were much lower than those of the parent compound. Carriomycin, lonomycin and etheromycin efficiently transported K+, Rb+ and Na+ through a CCl4 barrier. But did not carry Ca2+. These antibiotics caused a massive release of K+, Rb+ or Na+, but not of Li+ and Cs+, from mitochondria previously loaded with these cations by valinomycin or monazomycin. Thus, it is concluded that carriomycin, lonomycin and etheromycin are monovalent cation selective ionophores.
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000378:metabolism; D001692:Biological Transport; D002412:Cations / Q000378:metabolism; D055598:Chemical Phenomena; D002621:Chemistry; D066298:In Vitro Techniques; D007476:Ionophores / Q000378:metabolism; D008672:Metals, Alkali / Q000378:metabolism; D008930:Mitochondria, Liver / Q000378:metabolism; D008933:Mitochondrial Swelling; D051381:Rats
chemical_list: D000900:Anti-Bacterial Agents; D002412:Cations; D007476:Ionophores; D008672:Metals, Alkali