To study the efficiency ofDNA gyrase subunit B （gyrB） gene as means of diversity analysis, diversities of gyrB genes in three AMD samples collected from Dabaoshan Mine were studied by analyzing gyrB gene library. Ma...To study the efficiency ofDNA gyrase subunit B （gyrB） gene as means of diversity analysis, diversities of gyrB genes in three AMD samples collected from Dabaoshan Mine were studied by analyzing gyrB gene library. Many novel gyrB sequences and groups were detected. The results show that Acidithiobacillusferrooxidans-like bacteria represented 88.0% of the bacterial population in a sample. However, other two samples showed much high diversities. These diversities were characterized by the reciprocal of Simpson＇s index （l/D）, and show ferrous ion strongly influenced the composition of the microbial communities. The study indicate that gyrB Gene as a phylogenetic discriminator is a good tool to study different strains in same species that were difficult to be distinguished by 16S genes. But now gyrB Gene cannot define clearly unknown sequences to certain lineage, due to the incompleteness of the gyrB database.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
文摘To study the efficiency ofDNA gyrase subunit B （gyrB） gene as means of diversity analysis, diversities of gyrB genes in three AMD samples collected from Dabaoshan Mine were studied by analyzing gyrB gene library. Many novel gyrB sequences and groups were detected. The results show that Acidithiobacillusferrooxidans-like bacteria represented 88.0% of the bacterial population in a sample. However, other two samples showed much high diversities. These diversities were characterized by the reciprocal of Simpson＇s index （l/D）, and show ferrous ion strongly influenced the composition of the microbial communities. The study indicate that gyrB Gene as a phylogenetic discriminator is a good tool to study different strains in same species that were difficult to be distinguished by 16S genes. But now gyrB Gene cannot define clearly unknown sequences to certain lineage, due to the incompleteness of the gyrB database.
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.
