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2.
Vet Microbiol ; 157(3-4): 391-7, 2012 Jun 15.
Article in English | MEDLINE | ID: mdl-22266159

ABSTRACT

Risk of Campylobacter infection in humans has been associated with many sources, including dogs. C. upsaliensis is the most common species found in canines, and has been occasionally isolated from symptomatic humans. This study aimed to investigate the genetic diversity of 41 C. upsaliensis isolates carried by dogs and from nine isolates carried by humans using Multilocus sequence typing (MLST). We identified considerable genetic diversity amongst the C. upsaliensis isolates from both dogs and humans, identifying 45 different sequence types (STs). All STs were new, apart from that of the reference strain. Only three STs were found in more than one isolate: ST-72 (2 isolates), ST-98 (2 isolates) and ST-104 (3 isolates). ST-104 was the only ST to be encountered in both dogs and humans. Thirty-one of the 45 STs were assigned to one of 13 clonal complexes (CCs). Four of these CCs contained STs originating from both humans and dogs. None of the CCs contained exclusively human isolates, and two isolates from dogs within the same kennel belonged to the same CC. The large amount of diversity found in both dog and human isolates of C. upsaliensis, combined with the relatively small database, made it difficult to assign strains to sources of infection. This emphasizes the need to increase the size of the database. Dog and human isolates occasionally grouped together, however there were insufficient human-derived isolates to determine whether or not dogs are a common source of infection. Although C. upsaliensis infection is rare in humans, dogs still remain a potential source, and are therefore a possible zoonotic risk. Further work is needed to investigate the epidemiology of C. upsaliensis infection in humans.


Subject(s)
Campylobacter upsaliensis/classification , Dogs/microbiology , Genetic Variation , Multilocus Sequence Typing , Animals , Bacterial Typing Techniques , Campylobacter Infections/microbiology , Campylobacter Infections/veterinary , Campylobacter upsaliensis/genetics , Campylobacter upsaliensis/isolation & purification , DNA, Bacterial/genetics , Humans , Phylogeny , United Kingdom
3.
Appl Environ Microbiol ; 71(10): 6292-307, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16204551

ABSTRACT

Multiple strains of Campylobacter coli, C. jejuni, C. helveticus, C. lari, C. sputorum, and C. upsaliensis isolated from animal, clinical, or food samples have been analyzed by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Whole bacterial cells were harvested from colonies or confluent growth on agar and transferred directly into solvent and then to a spot of dried 3-methoxy-4-hydroxycinnamic acid (matrix). Multiple ions in the 5,000- to 15,000-Da mass range were evident in spectra for each strain; one or two ions in the 9,500- to 11,000-Da range were consistently high intensity. "Species-identifying" biomarker ions (SIBIs) were evident from analyses of multiple reference strains for each of the six species, including the genome strains C. jejuni NCTC 11168 and C. jejuni RM1221. Strains grown on nine different combinations of media and atmospheres yielded SIBI masses within +/-5 Da with external instrument calibration. The highest-intensity C. jejuni SIBIs were cytosolic proteins, including GroES, HU/HCj, and RplL. Multiple intraspecies SIBIs, corresponding probably to nonsynonymous nucleotide polymorphisms, also provided some intraspecies strain differentiation. MALDI-TOF MS analysis of 75 additional Campylobacter strains isolated from humans, poultry, swine, dogs, and cats revealed (i) associations of SIBI type with source, (ii) strains previously speciated incorrectly, and (iii) "strains" composed of more than one species. MALDI-TOF MS provides an accurate, sensitive, and rapid method for identification of multiple Campylobacter species relevant to public health and food safety.


Subject(s)
Bacterial Typing Techniques , Campylobacter/classification , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Animals , Campylobacter/chemistry , Campylobacter/growth & development , Campylobacter/isolation & purification , Campylobacter Infections/microbiology , Campylobacter Infections/veterinary , Campylobacter coli/chemistry , Campylobacter coli/classification , Campylobacter coli/growth & development , Campylobacter coli/isolation & purification , Campylobacter jejuni/chemistry , Campylobacter jejuni/classification , Campylobacter jejuni/growth & development , Campylobacter jejuni/isolation & purification , Campylobacter lari/chemistry , Campylobacter lari/classification , Campylobacter lari/growth & development , Campylobacter lari/isolation & purification , Campylobacter sputorum/chemistry , Campylobacter sputorum/classification , Campylobacter sputorum/growth & development , Campylobacter sputorum/isolation & purification , Campylobacter upsaliensis/chemistry , Campylobacter upsaliensis/classification , Campylobacter upsaliensis/growth & development , Campylobacter upsaliensis/isolation & purification , Cat Diseases/microbiology , Cats , Cattle , Culture Media , Dog Diseases/microbiology , Dogs , Food Microbiology , Humans , Species Specificity
4.
J Clin Microbiol ; 42(8): 3441-8, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15297481

ABSTRACT

Ninety-six Campylobacter upsaliensis strains that originated from Australia, Canada, and Europe (Germany) and that were isolated from humans, dogs, and cats were serotyped for their heat-stable surface antigens. All of them were genotyped by enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR) profiling, and 83 strains were genotyped by macrorestriction analysis with the endonuclease XhoI. Eighty-four percent of the strains belonged to five different serotypes (serotypes OI, OII, OIII, OIV, and OVI), with the proportions of strains in each serotype being comparable among the groups of strains from all three continents. Two serotypes, OIII and OIV, were prevalent at rates of 35 to 40%. Serotypes OI, OII, and OVI were detected at rates of 1.5 to 15%. Between 10 and 17.7% of the strains did not react with the available antisera. Analysis of the ERIC-PCR profiles revealed two distinct genotypic clusters, which represented the German and the non-European strains, respectively. XhoI macrorestriction yielded two genotypic clusters; one of them contained 80.2% of the German strains and 34.6% of the non-European strains, and the second cluster consisted of 65.4% of the non-European strains and 19.8% of the German strains. Fourteen strains from all three continents were analyzed for their 16S rRNA gene sequences. Only two minor variations were detected in four of the strains. In conclusion, C. upsaliensis has undergone diverging processes of genome arrangement on different continents during evolution without segregating into different subspecies.


Subject(s)
Campylobacter upsaliensis/genetics , Animals , Australia , Base Sequence , Campylobacter jejuni/classification , Campylobacter jejuni/genetics , Campylobacter jejuni/isolation & purification , Campylobacter upsaliensis/classification , Campylobacter upsaliensis/isolation & purification , Canada , Cats , Consensus Sequence , DNA Primers , DNA, Ribosomal/genetics , Dogs , Genotype , Geography , Germany , Humans , Introns/genetics , Phylogeny , Polymerase Chain Reaction/methods , RNA, Bacterial/genetics , RNA, Ribosomal, 23S/genetics , Sensitivity and Specificity
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