The spatial distribution pattern of organisms is a basic issue in understanding the mechanisms of community assembly. Although the spatial distributions of animals and plants have been well studied,those of microorgan...The spatial distribution pattern of organisms is a basic issue in understanding the mechanisms of community assembly. Although the spatial distributions of animals and plants have been well studied,those of microorganisms are still being debated. In this study, we used a fi sh gut microecosystem to detect the spatial pattern of microbes, because it can provide a relatively unifi ed and stable environment. Results suggest that the turnover of intestinal bacterial assemblages showed a weak but highly signifi cant negative correlation between similarity and distances in the microbial community, in respect of both grass carp intestinal loci distances and the geographical distance between fi sh sampling sites. Our results also suggest that intestinal bacterial assemblages responded to differences within the external environment and within different parts of the fi sh themselves. These results show that some, or possibly all, microbes are restricted in their distribution and that environmental factors are also important infl uences on the structure of intestinal bacterial assemblages. The fi sh gut microecosystem is useful in promoting study of the spatial distribution patterns of microorganisms.展开更多
AIM:To develop a new, rapid and accurate reverse dot blot(RDB) method for the detection of intestinal pathogens in fecal samples.METHODS:The 12 intestinal pathogens tested were Salmonella spp., Brucella spp., Escheric...AIM:To develop a new, rapid and accurate reverse dot blot(RDB) method for the detection of intestinal pathogens in fecal samples.METHODS:The 12 intestinal pathogens tested were Salmonella spp., Brucella spp., Escherichia coli O157:H7, Clostridium botulinum , Bacillus cereus , Clostridium perfringens , Vibrio parahaemolyticus , Shigella spp., Yersinia enterocolitica, Vibrio cholerae, Listeria monocytogenes and Staphylococcus aureus.The two universal primers were designed to amplify two variable regions of bacterial 16S and 23S rDNA genes from all of the 12 bacterial species tested.Five hundred and forty fecal samples from the diarrhea patients were detected using the improved RDB assay.RESULTS:The methods could identify the 12 intestinal pathogens specifi cally, and the detection limit was as low as 103 CFUs.The consistent detection rate of the improved RDB assay compared with the traditional culture method was up to 88.75%.CONCLUSION:The hybridization results indicated that the improved RDB assay developed was a reliable method for the detection of intestinal pathogen in fecal samples.展开更多
基金Supported by the National Basic Research Program of China(973 Program)(No.2009CB118705)the National Natural Science Foundation of China(Nos.30970358,31071896)the Youth Innovation Promotion Association,CAS
文摘The spatial distribution pattern of organisms is a basic issue in understanding the mechanisms of community assembly. Although the spatial distributions of animals and plants have been well studied,those of microorganisms are still being debated. In this study, we used a fi sh gut microecosystem to detect the spatial pattern of microbes, because it can provide a relatively unifi ed and stable environment. Results suggest that the turnover of intestinal bacterial assemblages showed a weak but highly signifi cant negative correlation between similarity and distances in the microbial community, in respect of both grass carp intestinal loci distances and the geographical distance between fi sh sampling sites. Our results also suggest that intestinal bacterial assemblages responded to differences within the external environment and within different parts of the fi sh themselves. These results show that some, or possibly all, microbes are restricted in their distribution and that environmental factors are also important infl uences on the structure of intestinal bacterial assemblages. The fi sh gut microecosystem is useful in promoting study of the spatial distribution patterns of microorganisms.
文摘AIM:To develop a new, rapid and accurate reverse dot blot(RDB) method for the detection of intestinal pathogens in fecal samples.METHODS:The 12 intestinal pathogens tested were Salmonella spp., Brucella spp., Escherichia coli O157:H7, Clostridium botulinum , Bacillus cereus , Clostridium perfringens , Vibrio parahaemolyticus , Shigella spp., Yersinia enterocolitica, Vibrio cholerae, Listeria monocytogenes and Staphylococcus aureus.The two universal primers were designed to amplify two variable regions of bacterial 16S and 23S rDNA genes from all of the 12 bacterial species tested.Five hundred and forty fecal samples from the diarrhea patients were detected using the improved RDB assay.RESULTS:The methods could identify the 12 intestinal pathogens specifi cally, and the detection limit was as low as 103 CFUs.The consistent detection rate of the improved RDB assay compared with the traditional culture method was up to 88.75%.CONCLUSION:The hybridization results indicated that the improved RDB assay developed was a reliable method for the detection of intestinal pathogen in fecal samples.
