Vanadium-binding protein excreted by vanadate-reducing bacteria.

A N Antipov; N N Lyalikova; N P L'vov

doi:10.1080/15216540050022467

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Vanadium-binding protein excreted by vanadate-reducing bacteria.

A N Antipov·N N Lyalikova·N P L'vov

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Abstract

A vanadium-binding protein was isolated from the culture medium of the vanadium-reducing bacterium Pseudomonas isachenkovii by utilizing vanadate as the terminal electron acceptor upon anaerobic respiration. The protein was associated with vanadium at a molar ratio of approximately 1:20. It was purified to homogeneity and separated into three components by treatment with 1 M HCl followed by gel filtration: a protein, a vanadium-binding ligand, and inorganic vanadium. Electron paramagnetic resonance analysis showed that vanadium was associated with the protein in the 4+ oxidation state. The distribution of vanadium within the cell was studied by electron microscopy and x-ray microanalysis of P. isachenkovii cells. The results suggest that vanadium, accumulated in special swells on the surface of the cell membranes, is reduced and excreted to the medium.

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Anaerobiosis Bacterial Proteins Carrier Proteins Chromatography, Gel Electron Probe Microanalysis Electron Spin Resonance Spectroscopy Microscopy, Electron Molecular Weight Oxidation-Reduction Pseudomonas Vanadates Journal Article Research Support, Non-U.S. Gov't

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A N Antipov, N N Lyalikova, N P L'vov. 2000. Vanadium-binding protein excreted by vanadate-reducing bacteria.. https://doi.org/10.1080/15216540050022467

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