Two acid mine drainage(AMD)samples TS and WK,which were from the Dachang metals-rich mine in Guangxi province,China,were studied using PCR-based cloning approach.A total of 44 operational taxonomic units(OTUs)were obt...Two acid mine drainage(AMD)samples TS and WK,which were from the Dachang metals-rich mine in Guangxi province,China,were studied using PCR-based cloning approach.A total of 44 operational taxonomic units(OTUs)were obtained from the two AMD samples.However,only three OTUs(GXDC-9,GXDC-19 and GXDC-50)detected in sample TS can also be observed in sample WK.Phylogenetic analysis revealed that the bacteria in the two samples fell into four putative divisions,which were Nitrospira,Alphaproteobacteria,Gamaproteobacteria,and Acidobacteria.Organisms of genuses Acidithiobacillus and Leptospirillum,which were in gamaproteobacteria class and Nitrospira family,were dominant in two samples,respectively.In sample TS,which was characterized by low pH,high sulfate,high iron,and high arsenide,two species(Acidithiobacillus ferrooxidans and Leptospirillum ferrooxidans)constituted 98.22% of the entire microbial community.Compared with sample TS,the microbial community in sample WK was more diversified according to the observation.Interestedly,the Legionella species,which was rarely observed in the low-pH environment,was detected in sample WK.This work helps us to further understand the diversity of microbial community living in extreme acid mine drainages with unique geochemistry and the tolerance capability of acidophiles to heavy metal.展开更多
To reveal the effects of Fe2＋ on bacterial communities in the early stages of minerals dissolution, two different acid mine drainage （AMD） samples were collected at Dabaoshan Mine and Shenbu Mine. Community success...To reveal the effects of Fe2＋ on bacterial communities in the early stages of minerals dissolution, two different acid mine drainage （AMD） samples were collected at Dabaoshan Mine and Shenbu Mine. Community successions of AMD niches were analyzed by Amplified Ribosomal DNA Restriction Analysis （ARDRA）, sequencing, and phylogenetic analysis in original AMD samples and their subculture under Fe2＋ concentrations. Although geochemical properties and community structures were greatly different between the two original AMD samples, bacterial community successions were still very similar under high Fe2＋ concentrations. The results showed that Acidithiobacillus ferrooxidans have competitive relationship with other bacterial species living in the AMD, including species that were also capable of oxidizing ferrous ion. A competitive relationship among different At. ferrooxidans strains likewise existed. Some of At. ferrooxidans can grow first under conditions of high ferrous ion concentration, and other At. ferrooxidans species decreased gradually and disappeared. This suggested that these species of At. ferrooxidans are most acidophilic bacteria and afford Fe3＋ to leach other metallic ion in the early stages of minerals dissolution.展开更多
基金Projects(50321402, 30428014, 50621063) supported by the National Natural Science Foundation of ChinaProject(2004CB619201) supported by the National Basic Research Program of China
文摘Two acid mine drainage(AMD)samples TS and WK,which were from the Dachang metals-rich mine in Guangxi province,China,were studied using PCR-based cloning approach.A total of 44 operational taxonomic units(OTUs)were obtained from the two AMD samples.However,only three OTUs(GXDC-9,GXDC-19 and GXDC-50)detected in sample TS can also be observed in sample WK.Phylogenetic analysis revealed that the bacteria in the two samples fell into four putative divisions,which were Nitrospira,Alphaproteobacteria,Gamaproteobacteria,and Acidobacteria.Organisms of genuses Acidithiobacillus and Leptospirillum,which were in gamaproteobacteria class and Nitrospira family,were dominant in two samples,respectively.In sample TS,which was characterized by low pH,high sulfate,high iron,and high arsenide,two species(Acidithiobacillus ferrooxidans and Leptospirillum ferrooxidans)constituted 98.22% of the entire microbial community.Compared with sample TS,the microbial community in sample WK was more diversified according to the observation.Interestedly,the Legionella species,which was rarely observed in the low-pH environment,was detected in sample WK.This work helps us to further understand the diversity of microbial community living in extreme acid mine drainages with unique geochemistry and the tolerance capability of acidophiles to heavy metal.
文摘To reveal the effects of Fe2＋ on bacterial communities in the early stages of minerals dissolution, two different acid mine drainage （AMD） samples were collected at Dabaoshan Mine and Shenbu Mine. Community successions of AMD niches were analyzed by Amplified Ribosomal DNA Restriction Analysis （ARDRA）, sequencing, and phylogenetic analysis in original AMD samples and their subculture under Fe2＋ concentrations. Although geochemical properties and community structures were greatly different between the two original AMD samples, bacterial community successions were still very similar under high Fe2＋ concentrations. The results showed that Acidithiobacillus ferrooxidans have competitive relationship with other bacterial species living in the AMD, including species that were also capable of oxidizing ferrous ion. A competitive relationship among different At. ferrooxidans strains likewise existed. Some of At. ferrooxidans can grow first under conditions of high ferrous ion concentration, and other At. ferrooxidans species decreased gradually and disappeared. This suggested that these species of At. ferrooxidans are most acidophilic bacteria and afford Fe3＋ to leach other metallic ion in the early stages of minerals dissolution.
