Aiming at development of transformation methods for alkalophilic Bacillus pseudofirmus JCM 9141 (growth at pH>10), screening conditions of transformants by using antibiotics were first examined to overcome the anti...Aiming at development of transformation methods for alkalophilic Bacillus pseudofirmus JCM 9141 (growth at pH>10), screening conditions of transformants by using antibiotics were first examined to overcome the antibiotic inactivation at high pH. Then, different transformation methods including competent cells, protoplast and electroporation were studied, respectively. The transformation efficiencies of competent cells and protoplast were low, while a modified electroporation method achieved higher transformation efficiency under 3000 V·cm -1. This method was also applicable to other alkalophilic Bacillus sps.展开更多
To reveal the impact of mining on bacterial ecology around mining area,bacterial community and geochemical characteristics about Dabaoshan Mine(Guangdong Province,China)were studied.By amplified ribosomal DNA restrict...To reveal the impact of mining on bacterial ecology around mining area,bacterial community and geochemical characteristics about Dabaoshan Mine(Guangdong Province,China)were studied.By amplified ribosomal DNA restriction analysis and phylogenetic analysis,it is found that mining pollution greatly impacts the bacterial ecology and makes the habitat type of polluted environments close to acid mine drainage(AMD)ecology.The polluted environment is acidified so greatly that neutrophil and alkaliphilic microbes are massively dead and decomposed.It provided organic matters that can make Acidiphilium sp.rapidly grow and become the most bacterial species in this niche.Furthermore,Acidithiobacillus ferrooxidans and Leptospirillum sp.are also present in this niche.The amount of Leptospirillum sp.is far more than that of Acidithiobacillus ferrooxidans,which indicates that the concentration of toxic ions is very high.The conclusions of biogeochemical analysis and microbiological monitor are identical. Moreover,because the growth of Acidithiobacillus ferrooxidans and Leptospirillum sp.depends on ferrous iron or inorganic redox sulfur compounds which can be supplied by continual AMD,their presence indicates that AMD still flows into the site.And the area is closer to the outfalls of AMD,their biomasses would be more.So the distinction of their biomasses among different areas can help us to find the effluent route of AMD.展开更多
文摘Aiming at development of transformation methods for alkalophilic Bacillus pseudofirmus JCM 9141 (growth at pH>10), screening conditions of transformants by using antibiotics were first examined to overcome the antibiotic inactivation at high pH. Then, different transformation methods including competent cells, protoplast and electroporation were studied, respectively. The transformation efficiencies of competent cells and protoplast were low, while a modified electroporation method achieved higher transformation efficiency under 3000 V·cm -1. This method was also applicable to other alkalophilic Bacillus sps.
基金Project(50621063)supported by the Science Fund for Creative Research Groups of ChinaProject(2004CB619201)supported by the Major State Basic Research Development Program of China
文摘To reveal the impact of mining on bacterial ecology around mining area,bacterial community and geochemical characteristics about Dabaoshan Mine(Guangdong Province,China)were studied.By amplified ribosomal DNA restriction analysis and phylogenetic analysis,it is found that mining pollution greatly impacts the bacterial ecology and makes the habitat type of polluted environments close to acid mine drainage(AMD)ecology.The polluted environment is acidified so greatly that neutrophil and alkaliphilic microbes are massively dead and decomposed.It provided organic matters that can make Acidiphilium sp.rapidly grow and become the most bacterial species in this niche.Furthermore,Acidithiobacillus ferrooxidans and Leptospirillum sp.are also present in this niche.The amount of Leptospirillum sp.is far more than that of Acidithiobacillus ferrooxidans,which indicates that the concentration of toxic ions is very high.The conclusions of biogeochemical analysis and microbiological monitor are identical. Moreover,because the growth of Acidithiobacillus ferrooxidans and Leptospirillum sp.depends on ferrous iron or inorganic redox sulfur compounds which can be supplied by continual AMD,their presence indicates that AMD still flows into the site.And the area is closer to the outfalls of AMD,their biomasses would be more.So the distinction of their biomasses among different areas can help us to find the effluent route of AMD.
