Proteomic Characterization of Cr(VI) resistent Bacteria In Wastewater Effluents

The emergence of micropollutants or heavy metals in natural matrices such as soil, sediments and water has been an issue of increasing concern in recent years. Cr(VI) is widely used by industries such as leather tanning, electroplating, wood preservation, manufacture of alloys and corrosion inhibitor in conventional and nuclear power plants. Bioremediation, i.e. microbiological decontamination can eliminate these compounds and this study illuminate several mechanisms of the degradation pathways or resistence mechanisms.
Bacterial strains able to degrade or tolerate extreme concentrations of heavy metals were isolated by enrichment cultures from locations in Turkey. Degradation or resistance characteristics were determined by quantitative proteomics for. Membrane and cytosolic fractions were prepared, digested in gel or in solution followed by high resolution shotgun sequencing using either nLC-QTOF MS or nUPLC-orbitrap MS. Alterations in Protein expression were determined label free quantitation. Bioinformatic investigation were accomplished by multiple approaches using Proteincenter, Ingenuity and multiple pathway mapping tools..
In this study, we present detailed investigations on four bacterial strains capable of tolerating extreme levels of Cr(VI) in vivo. The detailed investigation of four Cr(VI) tolerant bacterial strains also gave clear indications of novel gene products involved in the resistence mechanisms. A detailed mapping of the proteins involved in the tolerance are currently being confirmed by targeted approaches using SIM (Orbitrap).
References:
Proteomic changes in response to chromium(VI) toxicity in Pseudomonas aeruginosa. (2009) Kiliç NK, Stensballe A, Otzen DE, Dönmez G. Bioresour Technol. 2010 Apr;101(7):2134-40.