Resistance to copper in SRP

Sulfate-reducing prokaryotes (SRP) is a phylogenetically and physiologically diverse group of prokaryotes that can gain energy from dissimilatory reduction of sulfate. Acid mine drainage and waste water treatment plants represent the most important habitats where sulfidogenes are exposed to high metal concentrations.

We isolated SRP pure culture that could tolerate high copper concentrations (up to 15 g/l) in the growth medium from various mining sites and wastewater of metal processing plants.

Several SRB genomes, including Deltaproteobacteria, Firmicutes, and one Archaea, have been sequenced by present. The analysis of the genomes revealed that all Bacteria encode putative proteins with conserved domains (phosphorylation domain and nucleotide binding domain) that can be copper- and other metal-transporting P-type ATPases. CopA and CopB ATPases related to those of Enterococcus hirae have been confirmed only for a hyperthermophylic archaeon Archaeoglobus fulgidus. We showed that pcoA-related sequences could be amplified from the copper-tolerant SRP isolates

Phylogenetic position of copper-tolerant isolates. Methanobacterium formicicum was used as the outgroup reference. The scale represents an estimated 10% sequence divergence. Numbers beside branching points indicate bootstrap values determined from 1000 iterations.