Archaeal and bacterial communities of heavy metal contaminated acidic waters from zinc mine residues in Sepetiba Bay

Abstract

Mining of metallic sulfide ore produces acidic water with high metal concentrations that have harmful consequences for aquatic life. To understand the composition and structure of microbial communities in acid mine drainage (AMD) waters associated with Zn mine tailings, molecular diversity of 16S genes was examined using a PCR, cloning, and sequencing approach. A total of 78 operational taxonomic units (OTUs) were obtained from samples collected at five different sites in and around mining residues in Sepetiba Bay, Brazil. We analyzed metal concentration, physical, chemical, and microbiological parameters related to prokaryotic diversity in low metal impacted compared to highly polluted environments with Zn at level of gram per liter and Cd-Pb at level of microgram per liter. Application of molecular methods for community structure analyses showed that Archaea and Bacteria groups present a phylogenetic relationship with uncultured environmental organisms. Phylogenetic analysis revealed that bacteria present at the five sites fell into seven known divisions, alpha-Proteobacteria (13.4%), beta-Proteobacteria (16.3%), gamma-Proteobacteria (4.3%), Sphingobacteriales (4.3%), Actinobacteria (3.2%) Acidobacteria (2.1%), Cyanobacteria (11.9%), and unclassified bacteria (44.5%). Almost all archaeal clones were related to uncultivated Crenarchaeota species, which were shared between high impacted and low impacted waters. Rarefaction curves showed that bacterial groups are more diverse than archaeal groups while the overall prokaryotic biodiversity is lower in high metal impacted environments than in less polluted habitats. Knowledge of this microbial community structure will help in understanding prokaryotic diversity, biogeography, and the role of microorganisms in zinc smelting AMD generation and perhaps it may be exploited for environmental remediation procedures in this area.

Ecophysiology of Fe-Cycling Bacteria in Acidic Sediments

“…Picrophilaceae and Thermoplasmataleslike phylotypes (but not Ferroplasma related) were detected which were related to sequences from an extremely acidic, metal-rich stream in Spain (65). This result is similar to those from other acid mine drainage sites where Thermoplasmatales represent a dominant group (3,20,22,62) but contrasts with the results for other sites where Ferroplasma spp. appear to be responsible for pyrite leaching (20,21).…”

High Archaea diversity in Varvara hot spring, Bulgaria

“…Many of the sequences were closely related to previously reported environmental archaeal clones. Branching of the environmental sequences almost exclusively between unculturable Archaea has been already observed not only for hot springs [6,31] but also for other places where Archaea diversity was studied [32]. Most of the sequences retrieved in this study were related to Crenarchaeota, unlike the results from Panarea Iceland, where euryarchaeotic diversity in hydrothermal vents was significantly higher [33].…”

Bacterial Diversity in an Amazonian Mangrove Ecosystem

“…The represented bacterial groups are Proteobacteria, Bacterioidetes, Actinobacteria, Acidobacteria, Firmicutes, Chloroflexi, Spirochaetes, Cyanobacteria, and unclassified bacteria (Figures 5 and 6). These phyla are relatively common in the mangrove systems of southeastern Brazil (Almeida et al, 2009;Gomes et al, 2010;Santos et al, 2011;Silveira et al, 2011) and in other tropical and subtropical countries, such as India, China, Australia, and the United States (Zhang et al, 2008;Zhou et al, 2009), both aquatic and sedimentary communities Vieira et al, 2008).…”