The pathogenic species of genus Vibrio cause vibriosis, one of the most prevalent diseases of maricultured animals and seafood consumers. Monitoring their kinetics in the chain of seafood production, processing and co...The pathogenic species of genus Vibrio cause vibriosis, one of the most prevalent diseases of maricultured animals and seafood consumers. Monitoring their kinetics in the chain of seafood production, processing and consumption is of great importance for food and mariculture safety. In order to enrich Vibrio-representing 16S ribosomal RNA gene (rDNA) fragments and identify these bacteria further real-timely and synchronously among bacterial flora in the chain, a pair of primers that selectively amplify Vibrio 16S rDNA fragments were designed with their specificities and coverage testified in the analysis of seawater Vibrio community. The specificities and coverage of two primers, VF169 and VR744, were determined theoretically among bacterial 16S rDNAs available in GenBank by using BLAST program and practically by amplifying Vibrio 16S rDNA fragments from seawater DNA. More than 88.3% of sequences in GenBank, which showed identical matches with VR744, belong to Vibrio genus. A total of 33 clones were randomly selected and sequenced. All of the sequences showed their highest similarities to and clustered around those of diverse known Vibrio species. The primers designed are capable of retrieving a wide range of Vibrio 16S rDNA fragments specifically among bacterial flora in seawater, the most important natural environment of seafood cultivation.展开更多
The full length cDNA of a prion protein (PrP) encoding gene of guppy (Poecilia reticulata) and the corresponding ge-nomic DNA were cloned. The cDNA was 2245 bp in length and contained an open reading frame (ORF) of 15...The full length cDNA of a prion protein (PrP) encoding gene of guppy (Poecilia reticulata) and the corresponding ge-nomic DNA were cloned. The cDNA was 2245 bp in length and contained an open reading frame (ORF) of 1545 bp encoding a pro-tein of 515 amino acids,which held all typical structural characteristics of the functional PrP. The cloned genomic DNA fragment corresponding to the cDNA was 3720 bp in length,consisting of 2 introns and 2 exons. The 5’ untranslated region of cDNA origi-nated from the 2 exons,while the ORF originated from the second exon. Although the gene was transcribed in diverse tissues in-cluding brain,eye,liver,intestine,muscle and tail,its transcript was most abundant in the brain. In addition,the transcription of the gene was enhanced by 5 salinity,implying that it was associated with the response of guppy to saline stress.展开更多
基金This study was supported by grants from the International Found for Sciences(No.A/3224-1)Cooperative Project of the Key Lab of Freshwater Germplasm and Biotechnology of Chinese Ministry of Agriculture(No.LFB20040503)+1 种基金the National Natural Science Foundation of China(No.40176028)the National Key R&D Program(‘973'Program)of China(No.G1999012005).
文摘The pathogenic species of genus Vibrio cause vibriosis, one of the most prevalent diseases of maricultured animals and seafood consumers. Monitoring their kinetics in the chain of seafood production, processing and consumption is of great importance for food and mariculture safety. In order to enrich Vibrio-representing 16S ribosomal RNA gene (rDNA) fragments and identify these bacteria further real-timely and synchronously among bacterial flora in the chain, a pair of primers that selectively amplify Vibrio 16S rDNA fragments were designed with their specificities and coverage testified in the analysis of seawater Vibrio community. The specificities and coverage of two primers, VF169 and VR744, were determined theoretically among bacterial 16S rDNAs available in GenBank by using BLAST program and practically by amplifying Vibrio 16S rDNA fragments from seawater DNA. More than 88.3% of sequences in GenBank, which showed identical matches with VR744, belong to Vibrio genus. A total of 33 clones were randomly selected and sequenced. All of the sequences showed their highest similarities to and clustered around those of diverse known Vibrio species. The primers designed are capable of retrieving a wide range of Vibrio 16S rDNA fragments specifically among bacterial flora in seawater, the most important natural environment of seafood cultivation.
基金the Key Laboratory of Freshwater Germplasm and Biotechnology of Chinese Ministry of Agriculture,Yangtze River Fisheries Research Institute,Chinese Academy of Fishery Sciences (LFB20070601)the Key Laboratory of Mariculture of Chinese Ministry of Education,Ocean University of ChinaNational High Technology Research and Development Program of China (2007AA09Z427)
文摘The full length cDNA of a prion protein (PrP) encoding gene of guppy (Poecilia reticulata) and the corresponding ge-nomic DNA were cloned. The cDNA was 2245 bp in length and contained an open reading frame (ORF) of 1545 bp encoding a pro-tein of 515 amino acids,which held all typical structural characteristics of the functional PrP. The cloned genomic DNA fragment corresponding to the cDNA was 3720 bp in length,consisting of 2 introns and 2 exons. The 5’ untranslated region of cDNA origi-nated from the 2 exons,while the ORF originated from the second exon. Although the gene was transcribed in diverse tissues in-cluding brain,eye,liver,intestine,muscle and tail,its transcript was most abundant in the brain. In addition,the transcription of the gene was enhanced by 5 salinity,implying that it was associated with the response of guppy to saline stress.