Search results for "RESTRICTION FRAGMENT LENGTH POLYMORPHISM"
showing 10 items of 128 documents
Isolation and toxicity of Bacillus thuringiensis from potato-growing areas in Bolivia
2004
Bacillus thuringiensis was isolated from 116 samples collected in high altitude potato-growing areas in Bolivia. In these regions, main potato pests are the potato tuberworm Phthorimaea operculella, and the Andean weevils Premnotrypes latithorax and Rhigopsidius tucumanus. B. thuringiensis was found in 60% of the samples. The main percentage of samples with B. thuringiensis was found in larvae of R. tucumanus (78%). Bioassays were performed with 112 isolates. None resulted toxic to either larvae or adults of the two Andean weevils. However, 18 isolates from this study showed more toxicity against the beet armyworm Spodoptera exigua than the standard strain var. kurstaki isolated from DELFIN…
Human papillomavirus frequency in oral epithelial lesions
2005
BACKGROUND: Oral human papillomavirus (HPV) prevalence varies according to geographical occurrence, the type of lesion, and the method of diagnosis. The polymerase chain reaction method (PCR) appears to be more sensitive and can be easily applicable to epidemiologic studies. OBJECTIVES: To determine the frequency of HPV and its genotypes in oral lesions among patients attending a reference clinic of a university hospital. METHODS: PCR was performed to identify HPV DNA from samples of oral epithelial lesions in 80 patients. For HPV DNA amplification, MY09/MY11 consensus primers were used and specific genotypes were identified through restriction fragment of length polymorphism (RFLP) pattern…
Risultati di un test RFLP su ceppi vaccinali di Canine Distemper Virus in Italia
2013
Canine Distemper (CD) is a highly contagious and multisystemic viral disease of domestic and wild carnivores. A published Restriction Fragment Length Polymorphism (RFLP) test, based on the presence of a PsiI cleavage site on hemagglutinin (H) gene, allows a rapid differentiation of all currently used vaccine strains by virulent field strains. The present study describes the results of this test carried out on different CD vaccines available in Italy in 2010. RFLP has also revealed that the CD strain present in the Vanguard (Pfizer Animal Health) vaccine reacts as a wild-type strain. Moreover, genetic analysis of H gene sequence has showed that Vanguard vaccine strain does not cluster in the…
Study of the Evolutionary Relationships among Limonium Species (Plumbaginaceae) Using Nuclear and Cytoplasmic Molecular Markers
2000
The genus Limonium, due to the patchiness of the natural habitats of its species as well as the high frequency of hybridization and polyploidy and the possibility of reproduction by apomixis, provides an example of all the principal mechanisms of rapid speciation of plants. As an initial study of evolution in this genus, we have analyzed intra- and interspecific variability in 17 species from section Limonium, the largest in the genus, based on RFLPs of cpDNA and nuclear rDNA ITS sequences. In the cpDNA analysis, 21 restriction enzymes were used, resulting in 779 fragments, 490 of which were variable and 339 parsimony informative. L. furfuraceum exhibited two relatively divergent cpDNA hapl…
Molecular analysis of the catechol-degrading bacterial community in a coal wasteland heavily contaminated with PAHs
2010
International audience; A PCR-based molecular tool was developed to estimate the diversity of the catechol-degrading bacterial community in a coal wasteland heavily contaminated with PAHS. A degenerate primer pair specific to catA sequences was designed by multiple alignment of known sequences coding a key intermediate of the β-ketoadiapate pathway degrading catechol, namely catechol 1,2-dioxygenase. The specificity of this primer pair was assessed in 21 pure strains by PCR and sequencing. Comparison of the 16S rDNA and catA phylogenies revealed an absence of congruence between these two genes. The primer set was able to amplify catA sequences in DNA extracts from an industrial soil highly …
Evidence of Genomic Instability in Campylobacter jejuni Isolated from Poultry
1998
ABSTRACT Poultry isolates of Campylobacter jejuni derived from a survey of meat processing batches were genotyped by pulsed-field gel electrophoresis (PFGE) of chromosomal DNA to establish the clonal relationships between single-colony isolates. In the majority of batches studied, one or two genotype patterns predominated. However, in one batch (batch A), 21 single-colony isolates gave 14 different PFGE genotypes. The banding patterns obtained with Sma I were sufficiently different to distinguish between genotypes, although the patterns also produced many common bands. The question of whether these isolates represented different clones or had a common clonal ancestry was addressed by additi…
Genotypic characterization of Bradyrhizobium strains nodulating small Senegalese legumes by 16S-23S rRNA intergenic gene spacers and amplified fragme…
2000
ABSTRACT We examined the genotypic diversity of 64 Bradyrhizobium strains isolated from nodules from 27 native leguminous plant species in Senegal (West Africa) belonging to the genera Abrus , Alysicarpus , Bryaspis , Chamaecrista , Cassia , Crotalaria , Desmodium , Eriosema , Indigofera , Moghania , Rhynchosia , Sesbania , Tephrosia , and Zornia , which play an ecological role and have agronomic potential in arid regions. The strains were characterized by intergenic spacer (between 16S and 23S rRNA genes) PCR and restriction fragment length polymorphism (IGS PCR-RFLP) and amplified fragment length polymorphism (AFLP) fingerprinting analyses. Fifty-three reference strains of the different B…
Conservation of type III secretion system genes inBradyrhizobiumisolated from soybean
2006
International audience; The distribution of rhcRST genes encoding the type III secretion system (T3SS) in a collection of Bradyrhizobium strains was characterized by PCR and Southern blot hybridization. The polymorphism of the corresponding sequences amplified by PCR was characterized by RFLP and sequencing together with those available in the databank. Genomic group I is characterized by the presence of Bradyrhizobium elkanii strains and group II by the presence of B. japonicum and B. liaoningense strains. Highly conserved T3SS-like genes were detected by PCR in all Bradyrhizobium strains isolated from soybean belonging to genomic group II, and in none of the strains belonging to genomic g…
Distribution and diversity of type III secretion system-like genes in saprophytic and phytopathogenic fluorescent pseudomonads
2004
Type three secretion systems (TTSSs) are protein translocation mechanisms associated with bacterial pathogenicity in host plants, and hypersensitive reactions in non-host plants. Distribution and diversity of TTSS-like genes within a collection of saprophytic and phytopathogenic fluorescent pseudomonads were characterized. This collection included 16 strains belonging to 13 pathogenic species, and 87 strains belonging to five saprophytic species isolated from plant rhizosphere and soil. Presence of conserved hypersensitive reaction/pathogenicity (hrp) genes (hrc RST) was assessed both by PCR using primers designed to amplify the corresponding sequence and by dot-blot hybridization using a P…
Use of nodulation pattern, stress tolerance, nodC gene amplification, RAPD-PCR and RFLP-16S rDNA analysis to discriminate genotypes of Rhizobium legu…
2005
Twenty-seven new Rhizobium isolates were obtained from root nodules of wild and crop legumes belonging to the genera Vicia, Lathyrus and Pisum from different agroecological areas in central and southern Italy. A polyphasic approach including phenotypic and genotypic techniques was used to study their diversity and their relationships with other biovars and species of rhizobia. Analysis of symbiotic properties and stress tolerance tests revealed that wild isolates, showed a wide spectrum of nodulation and a marked variation in stress tolerance compared with reference strains tested in this study. All rhizobial isolates (except for the isolate CG4 from Galega officinalis) were presumptively i…