title: Phylogenetic and genetic characterization of Acidithiobacillus strains isolated from different environments.
abstract: To study the phylogenetic relationships and genetic heterogeneity of 21 Acidithiobacillus strains isolated from different environments, we amplified and sequenced the 16S-23S rRNA gene intergenic spacers (ITS) of all these strains. These sequence data, combined with related sequences available from GenBank, were divided into six phylogenetic groups by 16S rRNA gene and by 16S-23S rRNA gene sequence analysis. The results of phylogenetic analysis were consistent with those obtained by repetitive element PCR and arbitrarily primed PCR. In this research, the Acidithiobacillus ferrooxidans (A. ferrooxidans) strains were always separated into two groups in phylogenetic and cluster analyses. Genotypic analyses of the genes rusA, rusB, hip and iro suggest that these two groups may have different biochemical mechanisms for oxidizing ferrous iron. Strains in one A. ferrooxidans group were detected with rusA gene that encodes rusticyanin A which plays a very important role in the iron respiratory chain. The second A. ferrooxidans group was found to contain rusB gene which encode a homologous protein (RusB). The data suggested that ITS-based phylogeny is an effective tool to elucidate the relationships of Acidithiobacillus and that a different iron oxidation pathway may exist in different A. ferrooxidans groups.
authors.affiliation: School of Minerals Processing and Bioengineering, Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Biobuilding, Lushan South Road 932, Yuelu District, Changsha, 410083, Hunan Province, People's Republic of China.
authors.forename: Xueling
authors.initials: X
authors.lastname: Wu
authors.forename: Lili
authors.initials: L
authors.lastname: Liu
authors.forename: Zhenzhen
authors.initials: Z
authors.lastname: Zhang
authors.forename: Fanfan
authors.initials: F
authors.lastname: Deng
authors.forename: Xinxing
authors.initials: X
authors.lastname: Liu
mesh_terms: D042763:Acidithiobacillus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D004783:Environmental Microbiology; D005798:Genes, Bacterial; D005838:Genotype; D007501:Iron / Q000378:metabolism; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D021903:DNA, Ribosomal Spacer; D012336:RNA, Ribosomal, 16S; D007501:Iron