Characterization of a tandem repeat polymorphism in Rickettsia strains

Vitorino, Liliana; Sousa, Rita de; Bacellar, Fátima; Zé-Zé, Líbia

doi:10.1099/jmm.0.45956-0

Cited by 7 publications

(8 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The resulting electropherograms from the VNTR typing assay are in agreement with amplicon sizes assessed by agarose gel electrophoresis and with the sequencing data previously obtained for each rickettsiae 4 . Nevertheless, minor differences (1 bp [base pairs]) in the highest pick can be observed because 3′ adenine addition by the DNA polymerase.…”

Section: Resultssupporting

confidence: 87%

“…Hence, a fluorescent‐labeled primer was used to enable the analysis in an automated DNA‐sequencer device. The resulting electropherograms were in agreement with the results previously obtained 4 …”

Section: Introductionsupporting

confidence: 91%

“…The PCR reaction was carried out as previously descried, 4 using specific primers Rc‐65‐Fw, 5′‐TTG AGA AGG TTT ATA TCC CAT AG‐3′ and Rc‐65‐Rv, 5′‐TAC TAC CGC ATA TCC AAT TAA AAA‐3′. The reverse primer was 5′ labeled with dye D3 (Proligo).…”

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

Automated Method Based in VNTR Analysis for Rickettsiae Genotyping

Vitorino

Sousa

Bacellar

et al. 2006

Annals of the New York Academy of Sciences

View full text Add to dashboard Cite

A genetic locus named Rc-65, which is 5' adjacent to gene dksA and 3' adjacent to xerC gene, has previously been demonstrated to contain a VNTR with high discriminatory power in several rickettsial strains and thus, potentially useful for genetically similar strains identification. In this work, we present an automated molecular identification method based on capillary electrophoresis separation of VNTRs amplicons. The resulting electropherograms were in agreement with the sequence data obtained in a previous work. The presented genotyping method is fast and suitable for full automation, being a powerful tool for epidemiological surveillance in a large number of samples and enables the detection co-infected samples. The combination of other VNTR loci should improve the discriminatory capacity of this typing system, providing greater resolution and contributing to a more accurate VNTR-based assay. To our knowledge, this is the first automated assay for rickettsial strains identification.

show abstract

Section: Resultssupporting

confidence: 87%

Section: Introductionsupporting

confidence: 91%

See 1 more Smart Citation

Automated Method Based in VNTR Analysis for Rickettsiae Genotyping

Vitorino

Sousa

Bacellar

et al. 2006

Annals of the New York Academy of Sciences

View full text Add to dashboard Cite

show abstract

“…Furthermore, in Portugal, Vitorino et al . found no correlation between virulence of ISF strains and the dksA-xerC profile [30]. …”

Section: Discussionmentioning

confidence: 99%

Multispacer typing of Rickettsia isolates from humans and ticks in Tunisia revealing new genotypes

et al. 2013

View full text Add to dashboard Cite

BackgroundRickettsioses are important remerging vector born infections. In Tunisia, many species have been described in humans and vectors. Genotyping is important for tracking pathogen movement between hosts and vectors. In this study, we characterized Rickettsia species detected in patients and vectors using multispacer typing (MST), proposed by Founier et al. and based on three intergenic spacers (dksA-xerC, rmpE- tRNAfMet, mppA-pruC) sequencing.MethodsOur study included 25 patients hospitalized during 2009. Ticks and fleas were collected in the vicinity of confirmed cases. Serology was performed on serum samples by microimmunofluorescence using Rickettsia conorii and Rickettsia typhi antigens. To detect and identify Rickettsia species, PCR targeting ompA, ompB and gltA genes followed by sequencing was performed on 18 obtained skin biopsies and on all collected vectors. Rickettsia positive samples were further characterized using primers targeting three intergenic spacers (dksA-xerC, rmpE- tRNAfMet and mppA-purC).ResultsA rickettsial infection was confirmed in 15 cases (60%). Serology was positive in 13 cases (52%). PCR detected Rickettsia DNA in four biopsies (16%) allowing the identification of R. conorii subsp israelensis in three cases and R. conorii subsp conorii in one case. Among 380 collected ticks, nine presented positive PCR (2.4%) allowing the identification of six R. conorii subsp israelensis, two R. massiliae and one R. conorii subsp conorii. Among 322 collected fleas, only one was positive for R. felis. R. conorii subsp israelensis strains detected in humans and vectors clustered together and showed a new MST genotype. Similarly, R. conorii subsp conorii strains detected in a skin biopsy and a tick were genetically related and presented a new MST genotype.ConclusionsNew Rickettsia spotted fever strain genotypes were found in Tunisia. Isolates detected in humans and vectors were genetically homogenous despite location differences in their original isolation suggesting epidemiologic circulation of these strains.

show abstract

“…Such a variability makes the dksA-xerC the most discriminatory of the three spacers, with 42 genotypes identified. In a recent work, Vitorino et al proposed that PCR amplification of VNTRs within the dksA-xerC might serve to identify rickettsial isolates [53]. However, these authors only took into account the size of the VNTRs, not their sequence variability.…”

Section: Discussionmentioning

confidence: 99%