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1.
In the present review article, recent molecular advances relating to studies with Taylorella equigenitalis, as well as the recently described second species of the genus Taylorella, namely Taylorella asinigenitalis, have been described. Molecular genotyping of T. equigenitalis strains by pulsed-field gel electrophoresis (PFGE) after digestion with the suitable restriction enzyme(s) enabled the effective discrimination of strains, thus allowing the examination of the scientific mechanism(s) for its occurrence and transmission of contagious equine metritis (CEM). Alternatively, polymerase chain reaction (PCR) amplification and nucleotide sequencing of the 16S ribosomal DNA sequence and/or the other species specific sequence(s) as targets were confirmed to be effective for identification of T. equigenitalis. These new analytical methods at the genomic DNA level also enabled the discrimination of the newly discovered donkey-related T. asinigenitalis from T. equigenitalis, and moreover, the performance of phylogenetic analysis of genus Taylorella organisms with other closely related genera. Furthermore, detailed analysis of the genes responsible for CEM within the T. equigenitalis genome would be useful to help elucidate the pathogenic virulence and transmission mechanisms associated with the important equine pathogen associated with CEM.  相似文献   

2.
Analysis of chromosome-sized DNA and genome typing ofTaylorella equigenitalis NCTC11184, Kentucky 188, and five strains ofT. equigenitalis isolated in Japan were carried out. The three restriction enzymes used,ApaI,NaeI andNotI, cleaved the genomic DNAs of five Japanese strains ofT. equigenitalis into relatively limited numbers of restriction fragments, which were well resolved on crossed-field gel electrophoresis (CFGE). The respective profiles after CFGE of the restriction fragments from all five strains were essentially identical to each other after digestion byApaI,NaeI orNotI. Hence it appears that these strains have a common genome type with respect to these three restriction enzymes. It was also shown that the respective profiles from these strains were essentially different from those ofT. equigenitalis NCTC11184 and those of Kentucky 188 after digestion withApaI,NaeI orNotI.Abbreviations CFGE crossed-field gel electrophoresis - FIGE field inversion gel electrophoresis - PFGE pulsed-field gel electrophoresis  相似文献   

3.
The profiles, after digestion with ApaI or NotI and pulsed-field gel electrophoresis (PFGE), of genomic DNA from 18 strains of Taylorella equigenitalis isolated in Ireland were of three different types. The 13 strains in one of these types gave PFGE profiles identical to that of an American prototype strain, Kentucky 188, but different from strain NCTC11184T and from a strain isolated in Japan.Eight additional strains isolated in the United States gave four distinct types of genomic PFGE profiles. All four types were different from that of T. equigenitalis NCTC11184T or that of the Japanese strain. The profile of three strains of one type was identical to that of Kentucky 188.  相似文献   

4.
The total genomic DNAs from Trypanosoma evansi isolates of bubaline, equine and cameline origin were amplified by polymerase chain reaction using eight arbitrarily selected 10-base primers. Informative band patterns were obtained for all isolates analysed. Depending upon the T. evansi isolate–primer combination, between 1 and 11 reproducible DNA fingerprints of 205 to 3016 bp were amplified, suggesting minor and major differences in their RAPD (random amplified polymorphic DNA) profiles.  相似文献   

5.
采用任意引物PCR技术进行基因组差异显示   总被引：1，自引：0，他引：1  
任意引物ＰＣＲ技术是通过使用短的单一引物进行聚合酶链反应，能给基因组提供几百个多态性标记，它是分析基因组间差异的有力工具。它已被广泛用于物种的分类、鉴定、估计亲缘关系、混合基因组样本的分析及创造特异探针等。其主要优点是适用于任何生物、使用的量极少及其高效性和低成本。本文对这种技术的产生、原理、特点、应用及进展作一综述。  相似文献   

6.
A molecular technique based on the restriction fragment length polymorphism of the 16S ribosomal genes amplified by a polymerase chain reaction (PCR), referred to as amplified 16S ribosomal DNA restriction analysis (ARDRA), was designed to identify 19 Avibacterium paragallinarum strains isolated from infraorbital sinus and nasal turbinate bone samples of broiler chickens, breeders, and laying hens from different regions of Peru. The 16S rDNA was amplified by PCR using a pair of bacterial universal primers and restriction analysis of 16S rDNA sequences was done to select endonucleases with the highest number of cutting points inside the 16S rDNA. The DNA patterns with DdeI and RsaI endonucleases were identical for the 19 A. paragallinarum strains, but differed from those obtained for Ornithobacterium rhinotracheale, a bacterium with a high genetic and phenotypic resemblance to A. paragallinarum, as well as from Escherichia coli, a bacterium associated with infectious coryza. The ARDRA method could prove to be valuable for molecular identification of A. paragallinarum, a microorganism implicated in respiratory diseases in commercial birds.  相似文献   

7.
Profiles of the genomic DNA of 104 strains ofT. equigenitalis isolated from brood mares with contagious equine metritis in Hokkaido during the breeding seasons from 1980 to 1993, as well as those of five strains (SS28, EQ56, EQ59, EQ70 and HH139) previously isolated in Japan were examined after restriction digestion and crossed-field gel electrophoresis. These profiles were essentially identical to each other and the various isolates and strains appeared to have a common genotype, designated genotype J, with respect to two restriction enzymes,ApaI andNotI. These results suggest a common source for all these isolates obtained over the course of more than 10 years in Japan.Abbreviations CEM contagious equine metritis - CFGE crossed-field gel electrophoresis - PFGE pulsed-field gel electrophoresis  相似文献   

8.
Mycoplasma hyospnoviae strains from Denmark, Germany, Japan, Sweden, the Netherlands and the UK were examined for variations in the genomic DNA and within the 16S ribosomal RNA (rRNA) gene. Variations in the chromosomal DNA among 57 isolates recovered from the respiratory tract and joints of pigs, were investigated by analysis of amplified fragment length polymorphisms of the Bg/II and MfeI restriction sites and by pulsed-field gel electrophoresis of a BssHII digest of chromosomal DNA. Both methods allowed unambiguous differentiation of the analysed strains and showed similar discriminatory potential for the differentiation of M. hyosynoviae isolates. Concordant results obtained with the two whole-genome fingerprinting techniques evidence the considerable intraspecies genetic heterogeneity of M. hyosynoviae. Sixteen field strains of M. hyosynoviae and the type strain S16(T) were further examined for variation within the 16S rRNA gene. Ten field strains possessed the 16S rDNA sequences identical to the type strain, while the remaining six strains had sequences that differed by one to two nucleotides from that obtained from the type strain.  相似文献   

9.
为了解绵羊肺炎支原体(Mycoplasma ovi pneumoniae,Mo)在我国部分地区的流行病学特征,采用随机扩增多态性DNA(RAPD)及限制性片段长度多态性(RFLP)方法对26株Mo基因多态性进行了研究,并利用NTsys2.10e软件对获得的多态性图谱进行了聚类分析.结果在相似系数为0.70时,26株Mo可分成6个RAPD群或6个RFLP群;相似系数为0.90时,分成18个RAPD群或18个RFLP群;相似系数为1.00时,分成25个RAPD群或26个RFLP群.结果表明,我国Mo存在高度的基因多态性,这种多态性与地域差异相关,与宿主来源也具有一定的相关性.研究结果为了解我国Mo的分子流行病学特征打下了基础,也为建立有效的Mo诊断方法和疫苗研制提供了参考依据.  相似文献   

10.
A polymerase chain reaction (PCR) assay targeting the hyaC-hyaD gene was developed and used to identify strains of Pasteurella multocida belonging to serogroup-A. A set of serogroup-specific-PCR primers amplified a 564 bp product from genomic DNA prepared from bacterial cells or directly from bacterial colonies. This method detected as low as 10 ng of bacterial DNA and had a specificity of 100% for P. multocida serogroup-A. A nested PCR method yielded a single 374 bp product. All fifty isolates were also shown to be identical by restriction fragment length polymorphism (RFLP) analysis of the PCR products after digestion with BglII.  相似文献   

11.
Forty-six isolates of Taylorella equigenitalis were analysed by pulsed-field gel electrophoresis (PFGE) after separate digestion of the genomic DNA with ApaI and with NotI. The isolates had been obtained from horses in six European countries and were classified into 18 genotypes. In Belgium, 2 genotypes were detected in 2 isolates, in England 9 among 15, in Finland 2 in 2, in France 2 among 10, in Sweden 3 among 5, and in Switzerland 3 among 12. Two English isolates and 4 French isolates gave identical PFGE profiles to those of Kentucky 188 from the United States. A common genotype was found in 5 isolates from Belgium and England and also in 10 isolates from France and Switzerland. The analysis of genomic DNA from 12 isolates of T. equigenitalis obtained from male horses in France, Sweden and Switzerland gave no evidence of a sex-related difference in the genomic DNA. Genomic DNA from 11 streptomycin (STM)-susceptible isolates obtained in Sweden and Switzerland were classified into four genotypes by PFGE. Each of the six genotypes determined among the 17 isolates from these two countries had single phenotypes for resistance or susceptibility to STM.  相似文献   

12.
The objective of the present study was to characterize the phenotypic and molecular aspects of Campylobacter fetus strains isolated from bovine herds with reproductive problems. Thirty-one Brazilian field isolates, together with one reference strain of each subspecies of C. fetus, were analyzed. The strains were submitted to phenotypic identification followed by subspecies characterization using the polymerase chain reaction (PCR) and numeric evaluation of restriction fragment length polymorphism (RFLP) separated by pulsed-field gel electrophoresis (PFGE). Phenotypically, 4 isolates (12.1%) were classified as C. fetus subsp. fetus, and 29 isolates (87.9%) were classified as C. fetus subsp. venerealis. However, according to molecular analysis, only 1 isolate (3.0%) was classified as C. fetus subsp. fetus (the reference strain), whereas 32 isolates (97.0%) were considered C. fetus subsp. venerealis. SalI digestion of C. fetus genomic DNA, obtained from the 33 strains, yielded 7-10 DNA fragments ranging in size from 40 to 373kb, with 12 distinct patterns. Furthermore, the numeric analysis by neighbor-joining of the DNA from the 33 strains resulted in a dendrogram in which 2 distinct groups were identified. It was concluded that phenotypic characterization of C. fetus subspecies might lead to erroneous classification of field isolates. Although RFLP-PFGE is a powerful and reliable technique to characterize C. fetus, it has the inconvenience of being time consuming and laborious. Whereas PCR, besides providing rapid results, was found to be reliable and convenient for the characterization of field isolates of C. fetus.  相似文献   

13.
The reliability and reproducibility of random amplified polymorphic DNA analysis (RAPD) was compared with restriction fragment length polymorphism (RFLP) by analysing three virus strains isolated from zoo animals in Berlin and three isolates which were cultivated from pets from Northern Germany. The RAPD technique was evaluated as a reliable tool with good reproducibility of the patterns for each virus strain investigated. Problems of interpretation due to inconsistent intensity of bands in different polymerase chain reaction runs may arise for less experienced personnel. The RAPD analysis can be performed within one working day and needs less DNA compared with RFLP so costs will be reduced. The obvious advantage of RFLP is that the pattern can be traced to the recognition site of the restriction enzyme whereas the RAPD primer sequence is not present in the orthopoxvirus genome at all. To the authors knowledge, the RAPD technique has never been applied in DNA viruses before and they conclude that this technique is a useful tool for the discrimination of closely related cowpoxviruses.  相似文献   

14.
Unpurified DNA derived from cultures of equine fetal kidney cells infected with either equine herpesvirus type 1 or equine herpesvirus type 4 was amplified by the polymerase chain reaction using one pair of oligonucleotide primers. Restriction endonuclease digestion of the amplified segments with PvuII, followed by electrophoresis, revealed restriction fragment length polymorphisms which enabled the two virus types to be differentiated.  相似文献   

15.
凋亡素基因的克隆   总被引：6，自引：1，他引：5  
为了探索应用凋亡素杀死肿瘤细胞的可能性,用ＰＣＲ方法扩增了鸡贫血病毒（ｃｈｉｃｋｅｎａｎｅｍｉａｖｉｒｕｓ,ＣＡＶ）的ＶＰ３基因（凋亡素）片段,然后将该片段重组于ｐＵＣ１９载体,并进行了限制性内切酶鉴定与序列分析,证实该片段与鸡贫血病毒Ｃｕｘ－１株的ＶＰ３ＤＮＡ序列一致,该ＤＮＡ全长３６３ｂｐ,编码１２１个氨基酸。  相似文献   

16.
为了解山羊致病性大肠杆菌广西分离株的分子多态性,应用随机扩增多态性方法(RAPD)对山羊致病性大肠杆菌进行分型研究.从8条随机引物中筛选出4条能在10株大肠杆菌中具有较好多态性扩增的随机引物,4条随机引物共扩增出18条DNA片段,10个菌株无共有带谱,显示出良好的扩增多态性.菌株Nx31与Nx32曾被认为是同一菌株的两次分离,但是在RAPD分析中,两株细菌的带谱存在明显的差别,表明RAPD比传统的血清学分型具有更高的分辨性.  相似文献   

17.
Mycoplasma hyosynoviae strains from Denmark, Germany, Japan, Sweden, the Netherlands and the UK were examined for variations in the genomic DNA and within the 16S ribosomal RNA (rRNA) gene. Variations in the chromosomal DNA among 57 isolates recovered from the respiratory tract and joints of pigs, were investigated by analysis of amplified fragment length polymorphisms of the BglII and MfeI restriction sites and by pulsed‐field gel electrophoresis of a BssHII digest of chromosomal DNA. Both methods allowed unambiguous differentiation of the analysed strains and showed similar discriminatory potential for the differentiation of M. hyosynoviae isolates. Concordant results obtained with the two whole‐genome fingerprinting techniques evidence the considerable intraspecies genetic heterogeneity of M. hyosynoviae. Sixteen field strains of M. hyosynoviae and the type strain S16T were further examined for variation within the 16S rRNA gene. Ten field strains possessed the 16S rDNA sequences identical to the type strain, while the remaining six strains had sequences that differed by one to two nucleotides from that obtained from the type strain.  相似文献   

18.
中、西蜂纯种及其不同品系蜂的基因组DNA多态性分析   总被引：4，自引：1，他引：3  
使用P8(5‘-CCCACCCTTG-3‘)和W2（5‘-CGGCCCCGGT-3‘)随机引物，通过PRAPD（Random Amplified Polymorphic DNA)-PCR(polymerase chain reaction)遗传学分析，分别对中、西纯种蜂的不同品系的基因组DNA进行多态性分析。结果：中、西纯种蜂的不同品系的DNA多态4性图谱均具有明显的差异，从而为中、西纯种蜂的品系之间的鉴别提供了科学依据。  相似文献   

19.
《Veterinary microbiology》1998,62(3):243-250
Pulsed field gel electrophoresis analysis of genomic DNA was used to investigate genetic diversity among Dichelobacter nodosus from footrot in sheep in Malaysia. Twelve Dichelobacter nodosus strains isolated from lesion materials from infected sheep were confirmed as Dichelobacter nodosus by polymerase chain reaction technique using the species-specific Dichelobacter nodosus 16S RNA sequence Ac and C as primers. Pulsed field gel electrophoresis banding profiles using restriction enzymes ApaI (5′GGGCCC3′), SfiI (5′GGCCNNNNNGGCC3′)and SmaI (′5CCCGGG3′) enabled the 12 Dichelobacter nodosus strains to be differentiated into eight different PFGE patterns and thus genome-types, with F (coefficient of similarity) values ranging from 0.17 to 1.0 (ApaI), 0.14 to 1.0 (SfiI) and 0.22 to 1.0 (SmaI). Strains with origin in different farms were shown to have different PFGE patterns (two strains, M7 and M8 were the only exception). On the basis of their PFGE, all field strains used in the study differed from the reference strains. Our data revealed that there are several clonal types of Dichelobacter nodosus isolates and indicated that there is probably more than one source of this pathogen on the farms studied. The study showed that strains of D. nodosus exhibited considerable genetic diversity using this method and that genomic analysis by pulsed field gel electrophoresis was useful in discriminating the D. nodosus strains.  相似文献   

20.
The association of Mycoplasma cynos with canine infectious respiratory disease is increasingly being recognised. This study describes the strain typing of 14 M. cynos isolates cultured from trachea and bronchoalveolar lavage samples of six dogs with respiratory disease, from two separate kennels in the United Kingdom. The genetic similarity of the isolates was investigated using pulsed-field gel electrophoresis (PFGE) and random amplified polymorphic DNA (RAPD). Most of the isolates from four dogs housed at a re-homing kennel were genetically similar and some isolates from different dogs were indistinguishable by both PFGE and RAPD. These isolates were cultured from dogs with non-overlapping stays in the kennel, which may indicate maintenance of some strains within kennels. A small number of isolates showed much greater genetic heterogeneity and were genetically distinct from the main group of M. cynos strains. There was also a high degree of similarity of the M. cynos type strain (isolated from a dog with respiratory disease in Denmark in 1971) to at least one of the United Kingdom isolates using PFGE analysis, which may suggest possible conservation of pathogenic strains of M. cynos.  相似文献   

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