Nine strains resistant to five fluoroquinolones (Ciprofloxacin, Ofloxacin, Enrofloxacin, Danofloxacin, Sarafloxacin) were isolated from clinical samples and extracted the chromosomal DNA of these strains. Designed pri...Nine strains resistant to five fluoroquinolones (Ciprofloxacin, Ofloxacin, Enrofloxacin, Danofloxacin, Sarafloxacin) were isolated from clinical samples and extracted the chromosomal DNA of these strains. Designed primers to amplify the Quinolone-resistance-determining region(QRDR) of gyrB gene, then the PCR products were cloned and the sequence was analyzed. In comparison with the standarded strain NCTC5776, no mutation was found in the QRDR of gyrB gene of all resistant strains. The result indicated that the QRDR of gyrB has little relationship with fluoroquinolone resistance to salmonella.展开更多
Chitin is the most widespread amino polysaccharide in nature. Chitin synthase （CHS） plays an important role in chitin formation in the cuticle and the peritrophic membrane （PM） lining the midgut. Total RNA was iso...Chitin is the most widespread amino polysaccharide in nature. Chitin synthase （CHS） plays an important role in chitin formation in the cuticle and the peritrophic membrane （PM） lining the midgut. Total RNA was isolated from the cuticle of Mamestra brassicae （L.） fourth instar larva, cDNA sequence was cloned by RT-PCR and Rapid Amplification of cDNA Ends （RACE）. cDNA 5 220 bp in length, contained an open reading frame of 4 704 bp coding for a polypeptide of 1 567 amino acid residues with a predicted molecular weight of 178.3 ku and its pI was 6.42. The deduced amino acid sequence from Mi brassicae （L.） shared the high level of identity with chitin synthase sequences from other insects, especially lepidopteran insects, cDNA sequence has been deposited with GenBank under accession No. GQ281761展开更多
Degenerate primers were designed based on the conserved sequences of the Actin gene from other plants. Total RNA was extracted from the leaves of lris lacteal var.chinensis Fisch.Koidz. Actin gene fragment was obtaine...Degenerate primers were designed based on the conserved sequences of the Actin gene from other plants. Total RNA was extracted from the leaves of lris lacteal var.chinensis Fisch.Koidz. Actin gene fragment was obtained by reverse transcription polymerase chain reaction （RT-PCR） and cloned into pMD18-T vector. The positive clone identified by PCR was sequenced. The sequencing result showed that the Actin gene fragment from lris lacteal var.chinensis Fisch.Koidz contained about 598 bp, encoding 199 amino acids. Homology comparison with Actin gene sequences of other plants in the GenBank showed that it shared over 82% nueleotide sequence homology and 90% amino acid sequence homology. It indicated that this was the Actin gene. Because of the stability expression ofActin gene, it usually cited as the internal reference to study the expression and regulation of foundation in other genes of lris lacteal var.chinensis Fisch.Koidz well.展开更多
By means of PCR,the gene encoding gD of bovine herpesvirus-1 (BHV-1) strain Luojing was amplified,cloned and sequenced.The nucleotide sequence of this gD gene was (1 251 bp,)encoding 417 amino acids.Comparied with the...By means of PCR,the gene encoding gD of bovine herpesvirus-1 (BHV-1) strain Luojing was amplified,cloned and sequenced.The nucleotide sequence of this gD gene was (1 251 bp,)encoding 417 amino acids.Comparied with the published P8-2 strain,the homology of the necleotide sequence is 99.92%,and that of the deduced amino acid sequence is 100%.The results indicated that gD of BHV-1 was highly conservative.展开更多
In this paper,a 1,860 bp sequence in IRs region of duck enteritis virus(DEV) was amplified by single oligonucleotide nested PCR with a single primer designed according to partial sequence of US1 and then a pair of pri...In this paper,a 1,860 bp sequence in IRs region of duck enteritis virus(DEV) was amplified by single oligonucleotide nested PCR with a single primer designed according to partial sequence of US1 and then a pair of primers designed according to the 3' UTR of US8 gene and 5' end of the new getting sequence were used to amplify a 2,426 bp sequence toward the TRs region.Sequence analysis revealed that the both sequences contained an identical 990 bp open reading frame of DEV US1 gene.The two ORFs were in opposite transcription orientation.Sequence comparison of the nucleotide sequence and the deduced amino acid sequence of US1 gene showed relatively high identity to Mardivirus.Phylogenetic tree analysis showed that the eleven herpesviruses viruses were classified into three groups,and the duck enteritis virus was most closely related to Mardivirus.展开更多
Using double-stranded RNA(dsRNA)technology and sequence-independent amplification(SIA),the molecular identification on infected Rehmannia glutinosa in the field with mosaic symptoms was performed and the whole-genome ...Using double-stranded RNA(dsRNA)technology and sequence-independent amplification(SIA),the molecular identification on infected Rehmannia glutinosa in the field with mosaic symptoms was performed and the whole-genome of the Rehmannia mosaic virus(ReMV)Shanxi isolate(ReMV-SX)was sequenced.Sequencing analysis showed that the virus that infected Rehmannia glutinosa was Rehmannia mosaic virus(ReMV).The full-length of the obtained ReMV-SX sequence(GenBank accession no.JX575184)was 6395 nt,containing four open reading frames(ORFs).The sequence homology analysis of the complete nucleotide sequence showed that ReMV-SX was 93.8%-97.0%homologous to ReMV in Tobamovirus subgroup Ⅰ,while only 49.8%-58.9%homologous to the isolates in subgroups Ⅱ and Ⅲ of the same genus.Phylogenetic analysis showed that ReMV-SX and ReMV-Henan formed a separate branch and had the closest genetic relationship.The results laid the foundation for ongoing researches in the taxonomic status and evolution of ReMV and for further investigating the pathogenic mechanism of ReMV infecting Rehmannia glutinosa.展开更多
文摘Nine strains resistant to five fluoroquinolones (Ciprofloxacin, Ofloxacin, Enrofloxacin, Danofloxacin, Sarafloxacin) were isolated from clinical samples and extracted the chromosomal DNA of these strains. Designed primers to amplify the Quinolone-resistance-determining region(QRDR) of gyrB gene, then the PCR products were cloned and the sequence was analyzed. In comparison with the standarded strain NCTC5776, no mutation was found in the QRDR of gyrB gene of all resistant strains. The result indicated that the QRDR of gyrB has little relationship with fluoroquinolone resistance to salmonella.
基金Supported by Natural Science Foundation of Heilongjiang Province (C2007-7)Scientific and Technical Innovation Fund of Harbin (RC2006QN002027)Northeast Agricultural University Research Fund (2005)
文摘Chitin is the most widespread amino polysaccharide in nature. Chitin synthase （CHS） plays an important role in chitin formation in the cuticle and the peritrophic membrane （PM） lining the midgut. Total RNA was isolated from the cuticle of Mamestra brassicae （L.） fourth instar larva, cDNA sequence was cloned by RT-PCR and Rapid Amplification of cDNA Ends （RACE）. cDNA 5 220 bp in length, contained an open reading frame of 4 704 bp coding for a polypeptide of 1 567 amino acid residues with a predicted molecular weight of 178.3 ku and its pI was 6.42. The deduced amino acid sequence from Mi brassicae （L.） shared the high level of identity with chitin synthase sequences from other insects, especially lepidopteran insects, cDNA sequence has been deposited with GenBank under accession No. GQ281761
基金Supported by the Postdoctoral Scientific Research Foundation of Heilongjiang Province(LBH-Q10144)the Natural Science Foundation of Heilongjiang Province(C201112)Northeast Agricultural University Doctoral Research Fund(200830)
文摘Degenerate primers were designed based on the conserved sequences of the Actin gene from other plants. Total RNA was extracted from the leaves of lris lacteal var.chinensis Fisch.Koidz. Actin gene fragment was obtained by reverse transcription polymerase chain reaction （RT-PCR） and cloned into pMD18-T vector. The positive clone identified by PCR was sequenced. The sequencing result showed that the Actin gene fragment from lris lacteal var.chinensis Fisch.Koidz contained about 598 bp, encoding 199 amino acids. Homology comparison with Actin gene sequences of other plants in the GenBank showed that it shared over 82% nueleotide sequence homology and 90% amino acid sequence homology. It indicated that this was the Actin gene. Because of the stability expression ofActin gene, it usually cited as the internal reference to study the expression and regulation of foundation in other genes of lris lacteal var.chinensis Fisch.Koidz well.
文摘By means of PCR,the gene encoding gD of bovine herpesvirus-1 (BHV-1) strain Luojing was amplified,cloned and sequenced.The nucleotide sequence of this gD gene was (1 251 bp,)encoding 417 amino acids.Comparied with the published P8-2 strain,the homology of the necleotide sequence is 99.92%,and that of the deduced amino acid sequence is 100%.The results indicated that gD of BHV-1 was highly conservative.
基金Founding of Heilongjiang province education department major program(10541Z004)Heilongjiang province key scientific and technological program(GB04B504)
文摘In this paper,a 1,860 bp sequence in IRs region of duck enteritis virus(DEV) was amplified by single oligonucleotide nested PCR with a single primer designed according to partial sequence of US1 and then a pair of primers designed according to the 3' UTR of US8 gene and 5' end of the new getting sequence were used to amplify a 2,426 bp sequence toward the TRs region.Sequence analysis revealed that the both sequences contained an identical 990 bp open reading frame of DEV US1 gene.The two ORFs were in opposite transcription orientation.Sequence comparison of the nucleotide sequence and the deduced amino acid sequence of US1 gene showed relatively high identity to Mardivirus.Phylogenetic tree analysis showed that the eleven herpesviruses viruses were classified into three groups,and the duck enteritis virus was most closely related to Mardivirus.
基金Supported by the National Natural Science Foundation of China(31772130)China Agriculture Research System(CARS-21)。
文摘Using double-stranded RNA(dsRNA)technology and sequence-independent amplification(SIA),the molecular identification on infected Rehmannia glutinosa in the field with mosaic symptoms was performed and the whole-genome of the Rehmannia mosaic virus(ReMV)Shanxi isolate(ReMV-SX)was sequenced.Sequencing analysis showed that the virus that infected Rehmannia glutinosa was Rehmannia mosaic virus(ReMV).The full-length of the obtained ReMV-SX sequence(GenBank accession no.JX575184)was 6395 nt,containing four open reading frames(ORFs).The sequence homology analysis of the complete nucleotide sequence showed that ReMV-SX was 93.8%-97.0%homologous to ReMV in Tobamovirus subgroup Ⅰ,while only 49.8%-58.9%homologous to the isolates in subgroups Ⅱ and Ⅲ of the same genus.Phylogenetic analysis showed that ReMV-SX and ReMV-Henan formed a separate branch and had the closest genetic relationship.The results laid the foundation for ongoing researches in the taxonomic status and evolution of ReMV and for further investigating the pathogenic mechanism of ReMV infecting Rehmannia glutinosa.
