IRON UPTAKE BY THE MICROAEROPHILIC ANAEROBE BIFIDOBACTERIUM-BIFIDUM VAR PENNSYLVANICUS

  • 1 January 1984
    • journal article
    • research article
    • Vol. 2  (6) , 291-297
Abstract
A system was designed to investigate ferrous iron transport into B. bifidum var. pennsylvanicus. It involved the incubation of the organisms with labeled ferrous iron in the Norris medium at pH 5, in which the bacteria had grown. Fe uptakes were similar under aerobic and anaerobic conditions. Ferrous but not ferric iron was taken up by the organisms. Fe uptake showed saturation kinetics and a marked temperature dependence. 2,4-Dinitrophenol and thenoltrifluoroacetate but not azide or trypsin treatment inhibited Fe uptake. Zn inhibited Fe uptake competitively. Fe uptake from used medium was much greater than that from fresh medium at the same pH. Ferrous iron uptake by the microorganisms is a carrier-mediated active phenomenon, inhibited by Zn, which may involve a substance elaborated into the medium by the organism.