Proteomic responses of oxidative stress-resistant Arthrobacter globiformis 151B to Cr and Mg and the influence of Mg on the uptake process of Cr(III) and Cr(VI)

Abstract

In nature, there are some heavy-metal and oxidative stress resistant bacterial species, which can be used effectively for the environmental biotechnological purposes. They can participate in bioremediation processes: degrade aromatic compounds, uptake radioactive or heavy metals and reduce their carcinogenic activity. Different metals reveal synergist or antagonist effects on each other during their bioaccumulation processes. Knowing of the effects of a metal on another metal uptake processes by bacteria, is one of the actual issues for environmental protection biotechnologies. Arthrobacter globiformis 151B is an aerobic, basalt dwelling bacteria, isolated from heavy metal polluted Kazreti region (Georgia). Here we report the influence of magnesium (Mg) ions on the uptake capability of Cr(III) and Cr(VI) by A. globiformis 151B. The Influence of Mg(II) and Cr(VI) ions on the proteome of A. globiformis 151B have been studied. For identification the significantly differentially expressed proteins, two-dimensional (2-D) gel electrophoresis and Liquid chromatography mass spectrometry (LC-MS/MS) methods were used. We demonstrated that Mg(II) increased the accumulation of Cr(III) by A. globiformis 151B and decreased the uptake process of Cr(VI). Significant changes in protein expression involve different groups of proteins. Most remarkable changes were associated with proteins participating in oxidation-reduction processes. According to our earlier and present data, A. globiformis 151B is reactive oxygen species (ROS) resistant bacteria with great potential for bioremediation purposes.