Bacterial diversity in soils around a lead and zinc mine

Abstract

Five samples of soil collected from a lead and zinc mine were used to assess the effect of combined contamination of heavy metals on soil bacterial communities using a polyphasic approach including characterization of isolates by culture method, community level catabolic profiling in BIOLOG GN microplates, and genetic commuruty fingerprinting by denaturing gradient gel electrophoresis of 16s rDNA fragments amplified by PCR from community DNA ( P C R -W E ) . The structure of the bacterial community was affected to a certain extent by heavy metals. The PCR-DGGE analysis of 16s rRNA genes showed that there were significant differences in the structure of the mcrobial community among the soil samples, which were related to the contamination levels. The number of bactena and the number of denaturing gradient gel electrophoresis ( W E ) bands in the soils increased with increasing distance from the lead and zinc mine tailing, whereas the concentration of lead (Pb) and cadmium (Cd) was decreased. Heavily polluted soils could be characterized by a community that differs from those of lightly polluted soils in richness and structure of dominating bacterial populations. The clustering analysis of the DGGE profiles showed that the bacteria in all the five samples of soil belonged to three clusters. The data from the BIOLOG analysis also showed the same result. This study showed that heavy metal contamination decreased both the biomass and diversity of the bacterial community in soil.

Influence of geogenic factors on microbial communities in metallogenic Australian soils

“…However, these are likely to be second order influences within ecosystems, which are predominantly driven by geogenic factors. High concentrations of metals, for example in soils exposed to industrial pollution or mining, substantially alter microbial communities (Baker and Banfield 2003;Hu et al, 2007;Kock and Schippers, 2008;Denef et al, 2010). Similarly, amendment of soils with Cu, Pb, Zn and Cd strongly influences resident bacterial communities (Bååth, 1989;Abaye et al, 2005;Wakelin et al, 2010 a, b).…”

Effects of Metal and Metalloid Contamination on Microbial Diversity and Activity in Agricultural Soils

“…Most of these studies showed decreasing number of DGGE bands with increasing levels of metal pollution, indicating altered microbial communities (Wang et al, 2007a;Hu et al, 2007;Khan et al, 2007). Inverse relationship between band patterns and concentrations of Pb and Cd in soils that were contaminated with mine tailings has been reported (Hu et al, 2007;Khan et al, 2007). Using this technique, similar finding was reported by Sobolev and Begonia (2008) at low concentration of Pb, adding that the reduction was steady after radical increase in metal concentration from 0-2000 mg kg -1 .…”

“…This technique has been used extensively in the analysis of the impact of metal contamination to soil microbial population and diversity. Most of these studies showed decreasing number of DGGE bands with increasing levels of metal pollution, indicating altered microbial communities (Wang et al, 2007a;Hu et al, 2007;Khan et al, 2007). Inverse relationship between band patterns and concentrations of Pb and Cd in soils that were contaminated with mine tailings has been reported (Hu et al, 2007;Khan et al, 2007).…”

Removal of anthropogenic lead pollutions by a potent Bacillus species AS2 isolated from geogenic contaminated site

“…Arsenic-, cadmium-, copper-and zinc-resistant bacteria were isolated from gold, lead-zinc, copper and silver mine soils, respectively (Li et al 2013;PiotrowskaSeget et al 2005;Zhu et al 2012). Heavy metal tolerance of the microbial community in these environments could be acquired by genetically tolerance elements (genes involving in metal resistance are mostly presented in plasmids) and shift in species composition (Hu et al 2007). More than 90 % of bacterial strains obtained from Pb ore in this study could tolerate at least 100 ppm Pb.…”