Molecular characterization of Coxiella burnetii isolates by infrequent restriction site-PCR and MLVA typing.
BACKGROUND
Coxiella burnetii, the causative agent of Q fever, has a wide host range. Few epidemiological tools are available, and they are often expensive or not easily standardized across laboratories. In this work, C. burnetii isolates from livestock and ticks were typed using infrequent restriction site-PCR (IRS-PCR) and multiple loci variable number of tandem repeats (VNTR) analysis (MLVA).


RESULTS
By applying IRS-PCR, 14 C. burnetii isolates could be divided into six groups containing up to five different isolates. Clustering as deduced from MLVA typing with 17 markers provided an increased resolution with an excellent agreement to IRS-PCR, and with the plasmid type of each strain. MLVA was then applied to 28 additional C. burnetii isolates of different origin and 36 different genotypes were identified among the 42 isolates investigated. The clustering obtained is in agreement with published Multiple Locus Sequence Typing (MLST) data. Two panels of markers are proposed, panel 1 which can be confidently typed on agarose gel at a lower cost and in any laboratory setting (10 minisatellite markers with a repeat unit larger than 9 bp), and panel 2 which comprises 7 microsatellites and provides a higher discriminatory power.


CONCLUSIONS
Our analyses demonstrate that MLVA is a powerful and promising molecular typing tool with a high resolution and of low costs. The consistency of the results with independent methods suggests that MLVA can be applied for epidemiological studies. The resulting data can be queried on a dedicated MLVA genotyping Web service.
Arricau-Bouvery
Nathalie
N
INRA, Pathologie Infectieuse et Immunologie, 37380 Nouzilly, France. bouvery@tours.inra.fr
Hauck
Yolande
Y
Bejaoui
Awatef
A
Frangoulidis
Dimitrios
D
Bodier
Christelle C
CC
Souriau
Armel
A
Meyer
Hermann
H
Neubauer
Heinrich
H
Rodolakis
Annie
A
Vergnaud
Gilles
G
D000818:Animals; D002417:Cattle; D002642:Chick Embryo; D016000:Cluster Analysis; D016997:Coxiella burnetii / Q000145:classification* / Q000235:genetics*; D017931:DNA Primers / Q000737:chemistry; D005819:Genetic Markers; D005838:Genotype; D006801:Humans; D051379:Mice; D018895:Microsatellite Repeats / Q000235:genetics; D018598:Minisatellite Repeats / Q000235:genetics*; D010802:Phylogeny; D010957:Plasmids / Q000145:classification; D016133:Polymerase Chain Reaction / Q000379:methods*; D011778:Q Fever / Q000382:microbiology*; D013047:Specific Pathogen-Free Organisms
D017931:DNA Primers; D005819:Genetic Markers