REACTION OF FERRIC IRON BY SIDEROPHORE PRODUCED BY A BRADYRHIZOBIUM STRAIN

siderophores produced by microorganisms, help in the Fe nutrition of plants. Dicotyledonous plants absorb Fe in the ferrous (Fe+2) form. The ability of siderophores produced by a Brady-rhizobium strain, a rhizosphere bacterium of groundnut (Arachis hypogaea), to reduce Fe+3 was tested. Two Fe+3 (58Fe) binding fractions were separated from the culture supernatant of a Bradyrhizobium strain grown in an iron deficient medium. One of the fractions isolated reduced Fe+3 to Fe+2, unlike the synthetic chelator ethylenediaminetetraacetic acid (EDTA). It has been proposed that Fe-chelators supply Fe+3 to groundnut roots, and Fe+3 reduction to Fe+2 and its uptake occurs at the plasmalemma. Since siderophores can reduce Fe+++, they may help in Fe nutrition of groundnut plants better than chelators like EDTA. There is no evidence to indicated siderophore uptake Ferric iron (Fe+3) chelating compounds, including. Copyright © 1990, Taylor & Francis Group, LLC. All rights reserved.