Uptake of iron by symbiosomes and bacteroids from soybean nodules

FEBS Letters

Meyer, Jean-Marie²  Moreau, Sophie¹  Puppo, Alain¹ 

[1] Laboratoire de Biologie Végétale et Microbiologie, URA CNRS 1114, Universite de Nice-Sophia Antipolis, Parc Valrose, 06108 Nice Cedex 2, France;Laboratoire de Microbiologie, Université Louis-Pasteur, 67083 Strasbourg Cedex, France

关键词: Iron uptake;    Peribacteroid membrane;    Citrate;    Nitrogen fixation;    Root nodule;   

DOI  :  10.1016/0014-5793(95)00155-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Symbiosomes and bacteroids isolated from soybean nodules are able to take up the iron-citrate complex. The kinetics are characterized by initial high rates of iron internalization, and ATPase inhibitors significantly lower the uptake. This is consistent with an energy-dependent process on both membranes, although the involvement of a simultaneous facilitated diffusion can not be completely ruled out. Citrate alone is poorly absorbed by symbiosomes; this uptake is greatly enhanced by addition of iron. Iron-citrate was found both in the nodule cytosol and in the bacteroids. These results provide the first experimental evidence for the existence, at least in young nodules, of an important iron trafficking system from the plant host cell to the microsymbiont, through the peribacteroid membrane.

【 授权许可】

Unknown