The aim of the study was to examine the bacterial community associated with the intestinal mucus of young farmed puffer fish Takifugu rubripes. Polymerase chain reaction and partial 16 S r DNA sequencing was performed...The aim of the study was to examine the bacterial community associated with the intestinal mucus of young farmed puffer fish Takifugu rubripes. Polymerase chain reaction and partial 16 S r DNA sequencing was performed on DNA from bacteria cultivated on Zobell 2216 E medium. All the isolates were classified into two phyla—Proteobacteria and Firmicutes. Proteobacteria were the dominant, culturable intestinal microbiota(68.3%). At the genus level, V ibrio, Enterobacter, Bacillus, Pseudomonas, Exiguobacterium, Staphylococcus, Acinetobacter, Pseudoalteromonas and S hewanella were isolated from the intestine, with representatives of the genera V ibrio, Enterobacter and Bacillus accounting for 70.7% of the total. This is the first report of Enterobacter, Bacillus, Exiguobacterium and Staphylococcus as part of the intestinal bacterial microflora in T. rubripes. The profile of the culturable bacterial community differed between samples collected from the same tank at 2-month intervals, as indicated by Bray-Curtis and Sorensen indices, and the impact on the intestinal physiology and health of puffer fish requires further investigation.展开更多
Some novel members of extremely halophilic archaea,strains AJ11,AJ12 and AJ13,were isolated from the Aularz Lake located in the Altun Mountain National Nature Reserve of Xinjiang,Uygur Autonomous Region in China.Parti...Some novel members of extremely halophilic archaea,strains AJ11,AJ12 and AJ13,were isolated from the Aularz Lake located in the Altun Mountain National Nature Reserve of Xinjiang,Uygur Autonomous Region in China.Partial DNA fragments encoding a bacteriorhodopsin(BR),as well as for 16S rRNA of isolated strains,were amplified by PCR and their DNA sequences were determined subsequently.On the basis of homology and phylogenetic analysis of the 16S rDNA,we thought that the isolated strains forming a microbiological population are the members of the genus Natrinema.The results of genetic analysis,such as GC content,transition/transversion(Ti/Tv)rate ratios and synonymous substitution rates(Ks)indicate that the br fragments,with a high level of genetic divergence,are faced with both purifying selection and bias mutation pressure.The study provides the basis for use of species and BR proteins resources.展开更多
A slight halophilic heterotrophic nitrobacteria named gs1 was separated from the matured activated sludge. According to the morphological observation,physiological biochemical tests and sequence analysis of the 16S rD...A slight halophilic heterotrophic nitrobacteria named gs1 was separated from the matured activated sludge. According to the morphological observation,physiological biochemical tests and sequence analysis of the 16S rDNA,strain gs1 was identified to be as Pseudomonas sp. Sodium acetate and ammonium chloride were used as carbon and nitrogen sources,respectively,to investi-gate the characteristics of the bacterium. When cultured for 24 h under aerobic conditions,with the removal rates of the NH4+-N and COD being 82.2% and 74.73%,respectively,strain gs1 will have a nitrification function of producing NO2--N. When cultured for 24 h under aerobic conditions in nitrite medium,the removal rate of the NO2--N became 100%,and when cultured for 24 h under aerobic conditions in nitrate medium,the removal rate of the NO3--N became 97%. The result shows that this strain functions for either nitrification or denitrification,i.e.,it can complete the full process of biological deoxidation.展开更多
Halophilic archaeon AJ6 was isolated and purified from the Altun Mountain National Nature Reserve of the Xinjiang Uygur Autonomous Region.Strain AJ6 is a Gram-negative rod whose size is 0.2–0.6 by 1.6–4.2μm,wherein...Halophilic archaeon AJ6 was isolated and purified from the Altun Mountain National Nature Reserve of the Xinjiang Uygur Autonomous Region.Strain AJ6 is a Gram-negative rod whose size is 0.2–0.6 by 1.6–4.2μm,wherein a few cells are globular.The optimum salt concentration for its growth is 20%NaCl and 0.6%Mg^(2+),and the optimum pH is 6.0–7.0.Morphological,physiological,and biochemical characteristics of strain AJ6 were observed.The 16S rRNA encoding gene(16S rDNA)sequence of strain AJ6 was amplified by PCR,and its nucleotide sequence was determined subsequently.“Clustalw”and“PHYLIP”software bags were used to analyze the 16S rDNA sequence;the homology was compared,and then the phylogenetic tree was established.The results indicate that strain AJ6 is a novel species of the genus Natrinema.The GenBank accession number of the 16S rDNA sequences of strain AJ6 is AY277584.展开更多
基金Supported by the Public Science and Technology Research Funds Projects of Ocean(No.201205025)
文摘The aim of the study was to examine the bacterial community associated with the intestinal mucus of young farmed puffer fish Takifugu rubripes. Polymerase chain reaction and partial 16 S r DNA sequencing was performed on DNA from bacteria cultivated on Zobell 2216 E medium. All the isolates were classified into two phyla—Proteobacteria and Firmicutes. Proteobacteria were the dominant, culturable intestinal microbiota(68.3%). At the genus level, V ibrio, Enterobacter, Bacillus, Pseudomonas, Exiguobacterium, Staphylococcus, Acinetobacter, Pseudoalteromonas and S hewanella were isolated from the intestine, with representatives of the genera V ibrio, Enterobacter and Bacillus accounting for 70.7% of the total. This is the first report of Enterobacter, Bacillus, Exiguobacterium and Staphylococcus as part of the intestinal bacterial microflora in T. rubripes. The profile of the culturable bacterial community differed between samples collected from the same tank at 2-month intervals, as indicated by Bray-Curtis and Sorensen indices, and the impact on the intestinal physiology and health of puffer fish requires further investigation.
基金This work was supported by the National Natural Science Foundation of China(Grant No.30370029)the Scientific Research Start-up Foundation of Ningbo Institute of Technology,Zhejiang University(No.1140257G413).
文摘Some novel members of extremely halophilic archaea,strains AJ11,AJ12 and AJ13,were isolated from the Aularz Lake located in the Altun Mountain National Nature Reserve of Xinjiang,Uygur Autonomous Region in China.Partial DNA fragments encoding a bacteriorhodopsin(BR),as well as for 16S rRNA of isolated strains,were amplified by PCR and their DNA sequences were determined subsequently.On the basis of homology and phylogenetic analysis of the 16S rDNA,we thought that the isolated strains forming a microbiological population are the members of the genus Natrinema.The results of genetic analysis,such as GC content,transition/transversion(Ti/Tv)rate ratios and synonymous substitution rates(Ks)indicate that the br fragments,with a high level of genetic divergence,are faced with both purifying selection and bias mutation pressure.The study provides the basis for use of species and BR proteins resources.
基金Supported by the National Natural Science Foundation of China (50678085, 50878107)the Innovative Programs Foundation of Graduate Education in Shandong Province,China (SDYY07091) the Cultivate Pro-ject of Excellent Graduate Students’ Thesis of Qingdao University,China (YSPY2009014)
文摘A slight halophilic heterotrophic nitrobacteria named gs1 was separated from the matured activated sludge. According to the morphological observation,physiological biochemical tests and sequence analysis of the 16S rDNA,strain gs1 was identified to be as Pseudomonas sp. Sodium acetate and ammonium chloride were used as carbon and nitrogen sources,respectively,to investi-gate the characteristics of the bacterium. When cultured for 24 h under aerobic conditions,with the removal rates of the NH4+-N and COD being 82.2% and 74.73%,respectively,strain gs1 will have a nitrification function of producing NO2--N. When cultured for 24 h under aerobic conditions in nitrite medium,the removal rate of the NO2--N became 100%,and when cultured for 24 h under aerobic conditions in nitrate medium,the removal rate of the NO3--N became 97%. The result shows that this strain functions for either nitrification or denitrification,i.e.,it can complete the full process of biological deoxidation.
基金was supported by the National Natural Science Foundation of China (No.30370029).
文摘Halophilic archaeon AJ6 was isolated and purified from the Altun Mountain National Nature Reserve of the Xinjiang Uygur Autonomous Region.Strain AJ6 is a Gram-negative rod whose size is 0.2–0.6 by 1.6–4.2μm,wherein a few cells are globular.The optimum salt concentration for its growth is 20%NaCl and 0.6%Mg^(2+),and the optimum pH is 6.0–7.0.Morphological,physiological,and biochemical characteristics of strain AJ6 were observed.The 16S rRNA encoding gene(16S rDNA)sequence of strain AJ6 was amplified by PCR,and its nucleotide sequence was determined subsequently.“Clustalw”and“PHYLIP”software bags were used to analyze the 16S rDNA sequence;the homology was compared,and then the phylogenetic tree was established.The results indicate that strain AJ6 is a novel species of the genus Natrinema.The GenBank accession number of the 16S rDNA sequences of strain AJ6 is AY277584.
