THE DIVERSITY OF SULFUR-OXIDIZING BACTERIAL POPULATIONS AT AN IRANIAN COPPER MINE AND THE SURROUNDING AGRICULTURAL SOILS

Sulphur-oxidizing bacteria (SOB) are one of the most important metabolic types of bacteria living in very different soil environments. Mine environments with high concentrations of metals and extreme conditions have led to habitat-specific genera and operational taxonomic units (OTUs) of bacteria. In this study, we compared the diversity of SOB and non-SOB at the Sarcheshmeh Copper Mine Complex (Iran) with the surrounding agricultural soil. Thirty-six mine and agricultural sites were sampled aseptically and assessed by culture-dependent (full-length 16S rRNA cloning) and independent (Denaturing Gradient Gel Electrophoresis (DGGE)) approaches. Results indicated that soil samples from the copper mine region contained diverse OTUs affiliated with of SOB genera including Acidithiobacillus sp. and Sulfobacillus sp. and non-SOB including Pseudomonas sp., Bacillus sp., Sphingobium sp., Sphingomonas sp., Acinetobacter sp., Halospirulina sp., and Propionibacterium sp. In addition, the soil samples from the surrounding agricultural sites contained representatives of SOB genera as Thiobacillus sp., Starkeya sp. and non-SOB as Pseudomonas sp., Acinetobacter sp., Bacillus sp., Sphingobium sp., Streptomyces sp., and Propionibacterium sp. These bacterial communities were significantly affected by sulphur in the mine area, and by pH and calcium concentrations in the agricultural soils.