随着现代分子生物学技术的快速发展,动物胃肠道微生物领域的研究技术也进入了一个新的阶段。文章从传统及现代分子生物学两方面介绍了几种常用的研究动物胃肠道微生物技术及其应用进展,主要包括:传统微生物培养技术、16S r DNA序列分析...随着现代分子生物学技术的快速发展,动物胃肠道微生物领域的研究技术也进入了一个新的阶段。文章从传统及现代分子生物学两方面介绍了几种常用的研究动物胃肠道微生物技术及其应用进展,主要包括:传统微生物培养技术、16S r DNA序列分析技术、16S rRNA序列分析技术[变性梯度凝胶电泳(DGGE)、温度梯度凝胶电泳(TGGE)、单链构象多肽性(PCR-SSCP)、末段限制性长度多态性(T-RFLP)]、ERIC-PCR技术、RAPD技术等,并对动物肠道微生物研究技术的发展进行了展望。展开更多
目的采用基因分型方法对30株分离自西北三省的牛源分枝杆菌分离株进行鉴定。方法从西北三省的规模化奶牛场采集结核菌素(PPD)阳性奶牛的咽拭子和鼻拭子,经分离培养后,采用16S rRNA、MPT64以及多位点PCR进行菌株分型鉴定,利用数目可变串...目的采用基因分型方法对30株分离自西北三省的牛源分枝杆菌分离株进行鉴定。方法从西北三省的规模化奶牛场采集结核菌素(PPD)阳性奶牛的咽拭子和鼻拭子,经分离培养后,采用16S rRNA、MPT64以及多位点PCR进行菌株分型鉴定,利用数目可变串联重复序列分析(variable-number of tandem repeats,VNTR)和分枝杆菌散在分布重复单元(Mycobacterial interspersed repetitive unit,MIRU)连用的方法对其基因型进行了分析。结果菌株分型鉴定结果表明,30株牛源临床分离株全部为分枝杆菌属,其中,12株属于结核分枝杆菌复合群,18株属于非结核分枝杆菌;12株结核分枝杆菌中10株为牛分枝杆菌,2株为人型结核分枝杆菌。MIRU-VNTR分析结果表明,12株结核分枝杆菌呈现10种VNTR基因型,4株聚集为2个基因簇。结论30株分离株均属于分枝杆菌属,且结核分枝杆菌中以牛分枝杆菌为主。展开更多
The present study reports an improved PCR-based technique that allows quick and effective screening of cDNA libraries. First, the cDNA library was arrayed as follow: about 3 X 10’ cDNA clones were multiplied as indiv...The present study reports an improved PCR-based technique that allows quick and effective screening of cDNA libraries. First, the cDNA library was arrayed as follow: about 3 X 10’ cDNA clones were multiplied as individual plaques on solid medium in 24-well culture dishes at 1 200 plaque forming units per well. The phage suspension of each well was transferred to an individual microcentrifuge tube in 72-tube box. Then, box pool, row pools and column pools were set up that respectively represent a 72-tube box, rows and columns within the box. To screen a specific target cDNA,primers specific for novel ESTs ob- tained in our laboratory were employed to conduct PCR in a hierarchy mode. PCR began with the box pools, resulting in the identification of some Positive box pools. Then PCR went down to the row and col- umn pools of the positive box. The intersection of the positive row (s) and column (s) revealed the candi- date positive tubes. The specificity of PCR products were meanwhile checked by restriction enzyme diges- tion. Finally, hybridization was carried out to get single specific cDNA clomes from the positive tubes. This PCR-based technique features high specificity, high efficiency and less-cost in large-scale cDNA library screening. Our initial implementation of the technique resulted in the isolation of three longer different cD- NA clones from a human fetal brain cDNA library. Thus this improved technique can serve as an alterna-tive to the time-consuming and laborious conventional hybridization-based method for screening cDNA li-brary.展开更多
In Egypt,protection of cattle against lumpy skin disease (LSD) was carried out using a sheep poxvirus (Kenyan strain) vaccination strategy.In the present study 15 skin nodules from LSD suspected cows and 5 scab sample...In Egypt,protection of cattle against lumpy skin disease (LSD) was carried out using a sheep poxvirus (Kenyan strain) vaccination strategy.In the present study 15 skin nodules from LSD suspected cows and 5 scab samples from sheep pox (SP) suspected sheep were collected.Hyperimmune rabbit sera to Lumpy skin disease virus (LSDV)/Ismailyia88 strain and sheep pox virus (SPV)/ Kenyan vaccinal strain were prepared.The causative agent in the collected samples was identified using immunoflourescence (IF) and immunoperoxidase techniques.Of the 15 skin nodules suspected of LSD,10 showed a positive reaction and 3 out of 5 skin scabs suspected of sheeppox were found to be positive.An antigenic correlation between field skin isolate of LSDV,tissue culture adapted LSDV/Ismailyia88 strain,field skin isolate of SPV and SPV/Kenyan vaccinal strain was studied using prepared hyperimmune sera.Also,nucleotide sequence of the PCR amplified attachment gene fragments of field skin isolate of LSDV,tissue culture adapted LSDV/Ismailyia88 strain,field skin isolate of SPV and SPV /Kenyan vaccinal strain were compared.The results revealed that the four used viruses were antigenically identical.Sequence analysis indicated that field skin LSDV isolate is more related to tissue culture adapted LSDV/Ismailyia88 strain than to vaccinal SPV/ Kenyan strain and the skin isolate of SPV is more closely related to field skin isolate of LSDV than to SPV/Kenyan vaccinal strain.Thus,further study should be applied on the advantage of a LSD vaccine prepared from LSDV in protection of cattle against LSD compared to the commonly used sheep pox vaccine.展开更多
In order to understand the mechanisms of signal transduction and anti-desiccation mechanisms of Porphyra yezoensis, cDNA and its genomic sequence of Calmodulin gene (CaM) was cloned by the technique of polymerase chai...In order to understand the mechanisms of signal transduction and anti-desiccation mechanisms of Porphyra yezoensis, cDNA and its genomic sequence of Calmodulin gene (CaM) was cloned by the technique of polymerase chain reaction (PCR) based on the analysis of P. yezoensis ESTs from dbEST database. The result shows that the full-length cDNA of CaM consists of 603 bps including an ORF encoding for 151 amino acids and a terminate codon UGA, while the length of genomic sequence is 1231 bps including 2 exons and 1 intron. The average GC content of the coding region is 58.77%, while the GC content of the third position of this gene is as high as 82.23%. Four Ca2+ binding sites (EF-hand) are found in this gene. The predicted molecular mass of the deduced peptide is 16688.72 Da and the pI is 4.222. By aligning with known CaM genes, the similarity of CaM gene sequence with homologous genes in Chlamydomonas incerta and Chlamydomonas reinhardtii is 72.7% and 72.2% respectively, and the similarity of the deduced amino acid sequence of CaM gene with homologous genes in C. incerta and C. reinhardtii are both 71.5%. This is the first report on CaM from a species of Rhodophyta.展开更多
文摘随着现代分子生物学技术的快速发展,动物胃肠道微生物领域的研究技术也进入了一个新的阶段。文章从传统及现代分子生物学两方面介绍了几种常用的研究动物胃肠道微生物技术及其应用进展,主要包括:传统微生物培养技术、16S r DNA序列分析技术、16S rRNA序列分析技术[变性梯度凝胶电泳(DGGE)、温度梯度凝胶电泳(TGGE)、单链构象多肽性(PCR-SSCP)、末段限制性长度多态性(T-RFLP)]、ERIC-PCR技术、RAPD技术等,并对动物肠道微生物研究技术的发展进行了展望。
文摘目的采用基因分型方法对30株分离自西北三省的牛源分枝杆菌分离株进行鉴定。方法从西北三省的规模化奶牛场采集结核菌素(PPD)阳性奶牛的咽拭子和鼻拭子,经分离培养后,采用16S rRNA、MPT64以及多位点PCR进行菌株分型鉴定,利用数目可变串联重复序列分析(variable-number of tandem repeats,VNTR)和分枝杆菌散在分布重复单元(Mycobacterial interspersed repetitive unit,MIRU)连用的方法对其基因型进行了分析。结果菌株分型鉴定结果表明,30株牛源临床分离株全部为分枝杆菌属,其中,12株属于结核分枝杆菌复合群,18株属于非结核分枝杆菌;12株结核分枝杆菌中10株为牛分枝杆菌,2株为人型结核分枝杆菌。MIRU-VNTR分析结果表明,12株结核分枝杆菌呈现10种VNTR基因型,4株聚集为2个基因簇。结论30株分离株均属于分枝杆菌属,且结核分枝杆菌中以牛分枝杆菌为主。
基金National Natural Science Fund!(39392900 ) 863 High-tech Project Fund of China!(102-10-03-02 )
文摘The present study reports an improved PCR-based technique that allows quick and effective screening of cDNA libraries. First, the cDNA library was arrayed as follow: about 3 X 10’ cDNA clones were multiplied as individual plaques on solid medium in 24-well culture dishes at 1 200 plaque forming units per well. The phage suspension of each well was transferred to an individual microcentrifuge tube in 72-tube box. Then, box pool, row pools and column pools were set up that respectively represent a 72-tube box, rows and columns within the box. To screen a specific target cDNA,primers specific for novel ESTs ob- tained in our laboratory were employed to conduct PCR in a hierarchy mode. PCR began with the box pools, resulting in the identification of some Positive box pools. Then PCR went down to the row and col- umn pools of the positive box. The intersection of the positive row (s) and column (s) revealed the candi- date positive tubes. The specificity of PCR products were meanwhile checked by restriction enzyme diges- tion. Finally, hybridization was carried out to get single specific cDNA clomes from the positive tubes. This PCR-based technique features high specificity, high efficiency and less-cost in large-scale cDNA library screening. Our initial implementation of the technique resulted in the isolation of three longer different cD- NA clones from a human fetal brain cDNA library. Thus this improved technique can serve as an alterna-tive to the time-consuming and laborious conventional hybridization-based method for screening cDNA li-brary.
文摘In Egypt,protection of cattle against lumpy skin disease (LSD) was carried out using a sheep poxvirus (Kenyan strain) vaccination strategy.In the present study 15 skin nodules from LSD suspected cows and 5 scab samples from sheep pox (SP) suspected sheep were collected.Hyperimmune rabbit sera to Lumpy skin disease virus (LSDV)/Ismailyia88 strain and sheep pox virus (SPV)/ Kenyan vaccinal strain were prepared.The causative agent in the collected samples was identified using immunoflourescence (IF) and immunoperoxidase techniques.Of the 15 skin nodules suspected of LSD,10 showed a positive reaction and 3 out of 5 skin scabs suspected of sheeppox were found to be positive.An antigenic correlation between field skin isolate of LSDV,tissue culture adapted LSDV/Ismailyia88 strain,field skin isolate of SPV and SPV/Kenyan vaccinal strain was studied using prepared hyperimmune sera.Also,nucleotide sequence of the PCR amplified attachment gene fragments of field skin isolate of LSDV,tissue culture adapted LSDV/Ismailyia88 strain,field skin isolate of SPV and SPV /Kenyan vaccinal strain were compared.The results revealed that the four used viruses were antigenically identical.Sequence analysis indicated that field skin LSDV isolate is more related to tissue culture adapted LSDV/Ismailyia88 strain than to vaccinal SPV/ Kenyan strain and the skin isolate of SPV is more closely related to field skin isolate of LSDV than to SPV/Kenyan vaccinal strain.Thus,further study should be applied on the advantage of a LSD vaccine prepared from LSDV in protection of cattle against LSD compared to the commonly used sheep pox vaccine.
基金supported by the 863 Project (Nos. 2002AA628120, 2004AA628090, 20060110A4013 and 2006AA10A413)
文摘In order to understand the mechanisms of signal transduction and anti-desiccation mechanisms of Porphyra yezoensis, cDNA and its genomic sequence of Calmodulin gene (CaM) was cloned by the technique of polymerase chain reaction (PCR) based on the analysis of P. yezoensis ESTs from dbEST database. The result shows that the full-length cDNA of CaM consists of 603 bps including an ORF encoding for 151 amino acids and a terminate codon UGA, while the length of genomic sequence is 1231 bps including 2 exons and 1 intron. The average GC content of the coding region is 58.77%, while the GC content of the third position of this gene is as high as 82.23%. Four Ca2+ binding sites (EF-hand) are found in this gene. The predicted molecular mass of the deduced peptide is 16688.72 Da and the pI is 4.222. By aligning with known CaM genes, the similarity of CaM gene sequence with homologous genes in Chlamydomonas incerta and Chlamydomonas reinhardtii is 72.7% and 72.2% respectively, and the similarity of the deduced amino acid sequence of CaM gene with homologous genes in C. incerta and C. reinhardtii are both 71.5%. This is the first report on CaM from a species of Rhodophyta.
