The variation of microbial community structure was investigated for the tank bioleaching process of Pb-Zn-Sn chalcopyrite concentrate in the presence of mixed moderately thermophilic bacteria. The parameters, such as ...The variation of microbial community structure was investigated for the tank bioleaching process of Pb-Zn-Sn chalcopyrite concentrate in the presence of mixed moderately thermophilic bacteria. The parameters, such as pH value, solution potential and concentrations of metal ions, were determined by the method of polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） to analyze the succession of microbial community. The results showed that a final copper extraction rate of 85.6% could be obtained after tank bioleaching for 30 d. The Acidithiobacillus caldus was the dominant population with abundance of about 73.80%in the initial stage, then Sulfobacillus thermosulfidooxidans dominated from the 18th day to the end of bioleaching, while the abundance of Leptospirillum ferriphilum changed slightly. A higher solution potential within a certain range and appropriate concentration of ferric ions were essential for this tank bioleaching of chalcopyrite.展开更多
The narG gene is frequently used as a molecular marker for bacterial nitrate-reducing community analysis. In this study, a new set of primers targeting the narG gene was designed and applied to semi-nested polymerase ...The narG gene is frequently used as a molecular marker for bacterial nitrate-reducing community analysis. In this study, a new set of primers targeting the narG gene was designed and applied to semi-nested polymerase chain reaction-denaturing gradient gel electrophoresis （PCR-DGGE） assay. The potential of the new primers was verified on DNA directly extracted from soils from five different experimental sites distributed in Central and Southern Italy. Specificity of the primers was determined by excision, amplification, and sequencing of bands resolved by DGGE. A phylogenetic analysis showed the correlation between the sequences retrieved from the soils studied and the narG sequences from βand y-Proteobacteria. These primers expanded the existing molecular tools for ecological study on the size and diversity of nitrate-reducing bacterial community in soil.展开更多
Two new photolabile nucleotide analogues with furan-fused deoxyuridine were synthesized through Sonogashira coupling.Their enzymatic incorporation into DNA was evaluated with two DNA polymerases(Taq and Deep vent exo-...Two new photolabile nucleotide analogues with furan-fused deoxyuridine were synthesized through Sonogashira coupling.Their enzymatic incorporation into DNA was evaluated with two DNA polymerases(Taq and Deep vent exo-)by polymerase chain reaction(PCR).Deep vent exo-recognized both nucleotides as substrates for primer extension,while Taq was much less proficient.Light irradiation of PCR products released the amino and carboxyl moieties of DNA.Further labeling with fluorescein isothiocyanate for a long DNA construct with F-dUnTP incorporation was successfully achieved.展开更多
基金Project (51374248) supported by the National Natural Science Foundation of ChinaProject (NCET-13-0595) supported by the Program for New Century Excellent Talents in University,China+3 种基金Project (2012AA061501) supported by the High-tech Research and Development Program of ChinaProject (2010CB630905) supported by the National Basic Research Program of ChinaProject (20120162120010) supported by the Research Fund for the Doctoral Program of Higher Education of ChinaProject (CSUZC2012020) supported by the Open-End Fund for the Valuable in Central South University,China
文摘The variation of microbial community structure was investigated for the tank bioleaching process of Pb-Zn-Sn chalcopyrite concentrate in the presence of mixed moderately thermophilic bacteria. The parameters, such as pH value, solution potential and concentrations of metal ions, were determined by the method of polymerase chain reaction-restriction fragment length polymorphism （PCR-RFLP） to analyze the succession of microbial community. The results showed that a final copper extraction rate of 85.6% could be obtained after tank bioleaching for 30 d. The Acidithiobacillus caldus was the dominant population with abundance of about 73.80%in the initial stage, then Sulfobacillus thermosulfidooxidans dominated from the 18th day to the end of bioleaching, while the abundance of Leptospirillum ferriphilum changed slightly. A higher solution potential within a certain range and appropriate concentration of ferric ions were essential for this tank bioleaching of chalcopyrite.
基金Supported by the Integrated Special Fund for Research (FISR), Italy
文摘The narG gene is frequently used as a molecular marker for bacterial nitrate-reducing community analysis. In this study, a new set of primers targeting the narG gene was designed and applied to semi-nested polymerase chain reaction-denaturing gradient gel electrophoresis （PCR-DGGE） assay. The potential of the new primers was verified on DNA directly extracted from soils from five different experimental sites distributed in Central and Southern Italy. Specificity of the primers was determined by excision, amplification, and sequencing of bands resolved by DGGE. A phylogenetic analysis showed the correlation between the sequences retrieved from the soils studied and the narG sequences from βand y-Proteobacteria. These primers expanded the existing molecular tools for ecological study on the size and diversity of nitrate-reducing bacterial community in soil.
基金supported by the National Natural Science Foundation of China(21072015)the National Basic Research Program of China(973 Program,2012CB720600)+1 种基金the Program for New Century Excellent Talents in University(NCET-10-0203)the State Key Laboratory of Drug Research(SIMM1106KF-15)
文摘Two new photolabile nucleotide analogues with furan-fused deoxyuridine were synthesized through Sonogashira coupling.Their enzymatic incorporation into DNA was evaluated with two DNA polymerases(Taq and Deep vent exo-)by polymerase chain reaction(PCR).Deep vent exo-recognized both nucleotides as substrates for primer extension,while Taq was much less proficient.Light irradiation of PCR products released the amino and carboxyl moieties of DNA.Further labeling with fluorescein isothiocyanate for a long DNA construct with F-dUnTP incorporation was successfully achieved.
