Abstract
Iron uptake from two Fe3+-hydroxamate siderophores, ferrioxamine B and Fe3+-rhodotorulate, by iron-stressed Chlorella vulgaris (ATCC strain 11468) was evaluated with some comparison to iron uptake from synthetic and organic acid ferric chelates. Iron-stress induced iron uptake from ferrioxamine B. Dissipation of the electrochemical gradient, via uncouplers, inhibited iron uptake. Respiratory inhibitors gave variable results, an indication that a direct link to respiration was not apparent. Vanadate inhibition of iron uptake indicated that an ATPase or phosphate intermediate could be involved in the uptake mechanism. Divalent cations manifested variable effects dependent on the cation and chelator used. These data confirm that C. vulgaris has an inducible iron-uptake system for Fe3+-hydroxamic acid siderophores which may involve a different mechanism than that observed for other chelates.
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Selected References
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- Allnutt F. C., Bonner W. D. Evaluation of Reductive Release as a Mechanism for Iron Uptake from Ferrioxamine B by Chlorella vulgaris. Plant Physiol. 1987 Nov;85(3):751–756. doi: 10.1104/pp.85.3.751. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Atkin C. L., Neilands J. B. Rhodotorulic acid, a diketopiperazine dihydroxamic acid with growth-factor activity. I. Isolation and characterization. Biochemistry. 1968 Oct;7(10):3734–3739. doi: 10.1021/bi00850a054. [DOI] [PubMed] [Google Scholar]
- Cline G. R., Reid C. P., Powell P. E., Szaniszlo P. J. Effects of a hydroxamate siderophore on iron absorption by sunflower and sorghum. Plant Physiol. 1984 Sep;76(1):36–39. doi: 10.1104/pp.76.1.36. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Emery T., Hoffer P. B. Siderophore-mediated mechanism of gallium uptake demonstrated in the microorganism Ustilago sphaerogena. J Nucl Med. 1980 Oct;21(10):935–939. [PubMed] [Google Scholar]
- Leong J., Neilands J. B. Mechanisms of siderophore iron transport in enteric bacteria. J Bacteriol. 1976 May;126(2):823–830. doi: 10.1128/jb.126.2.823-830.1976. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Li E. L., Perdue J. F. An airfuge centrifugation procedure for the measurement of ligand binding to membrane-associated and detergent-solubilized plasma membrane receptors. J Biochem Biophys Methods. 1980 Oct;3(4):207–217. doi: 10.1016/0165-022x(80)90059-7. [DOI] [PubMed] [Google Scholar]
- Stutz E. Aufnahme von Ferrioxamin B durch Tomatenpflanzen. Experientia. 1964 Aug 15;20(8):430–431. doi: 10.1007/BF02152129. [DOI] [PubMed] [Google Scholar]