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N P French - One of the best experts on this subject based on the ideXlab platform.

  • 2005) Prevalence and genetic diversity of Campylobacter spp. in environmental water samples from a 100-square-kilometer predominantly dairy farming
    2008
    Co-Authors: R. Kemp, J. Turner, E. J. Wright, N P French
    Abstract:

    Water samples were taken systematically from a 100-km 2 area of mainly dairy farmland in northwestern England and examined for Campylobacter spp. Pulsed-field gel electrophoresis–restriction fragment length polymorphism (PFGE-RFLP) and flaA strain typing of Campylobacter jejuni and Campylobacter coli isolates were done. Data on the water source and the adjacent environment were recorded and examined as explanatory variables. Campylobacter spp. were isolated from 40.5 % (n � 119) of the water samples tested. C. jejuni was isolated from 14.3%, C. coli was isolated from 18.5%, and Campylobacter Lari was isolated from 4.2 % of the samples. Campylobacter hyointestinalis was not isolated from any water source. The difference in prevalence between water types (trough, running, and standing) was significant (P � 0.001). C. jejuni was the species most commonly isolated from trough-water and running-water sources, while C. coli was the most frequently isolated from standing water (P < 0.001). No association was found between the presence of Escherichia coli and that of Campylobacter spp. The final multivariable logistic regression model for Campylobacter spp. included the following variables: water source, soil type, aspect, and amount of cattle fecal material in the environment (fecal pat count). Strain typing demonstrated a diverse population of C. jejuni and the presence of a common C. coli flaA type that was widely distributed throughout the area. Most of the isolates within the common flaA type were discriminated by PFGE-RFLP. These findings suggest a possible role for environmental water in th

  • prevalence and genetic diversity of Campylobacter spp in environmental water samples from a 100 square kilometer predominantly dairy farming area
    Applied and Environmental Microbiology, 2005
    Co-Authors: R. Kemp, J. Turner, E. J. Wright, A J H Leatherbarrow, Nicola J Williams, C A Hart, Helen E Clough, N P French
    Abstract:

    Water samples were taken systematically from a 100-km2 area of mainly dairy farmland in northwestern England and examined for Campylobacter spp. Pulsed-field gel electrophoresis-restriction fragment length polymorphism (PFGE-RFLP) and flaA strain typing of Campylobacter jejuni and Campylobacter coli isolates were done. Data on the water source and the adjacent environment were recorded and examined as explanatory variables. Campylobacter spp. were isolated from 40.5% (n = 119) of the water samples tested. C. jejuni was isolated from 14.3%, C. coli was isolated from 18.5%, and Campylobacter Lari was isolated from 4.2% of the samples. Campylobacter hyointestinalis was not isolated from any water source. The difference in prevalence between water types (trough, running, and standing) was significant (P = 0.001). C. jejuni was the species most commonly isolated from trough-water and running-water sources, while C. coli was the most frequently isolated from standing water (P < 0.001). No association was found between the presence of Escherichia coli and that of Campylobacter spp. The final multivariable logistic regression model for Campylobacter spp. included the following variables: water source, soil type, aspect, and amount of cattle fecal material in the environment (fecal pat count). Strain typing demonstrated a diverse population of C. jejuni and the presence of a common C. coli flaA type that was widely distributed throughout the area. Most of the isolates within the common flaA type were discriminated by PFGE-RFLP. These findings suggest a possible role for environmental water in the epidemiology of Campylobacter spp. in a farming environment.

Peter Vandamme - One of the best experts on this subject based on the ideXlab platform.

  • Comparative Genomics of the Campylobacter Lari Group
    Genome biology and evolution, 2014
    Co-Authors: William G. Miller, Peter Vandamme, Craig T. Parker, Emma Yee, Mary H. Chapman, T. P. L. Smith, James L. Bono, Steven Huynh, Khai Luong, Jonas Korlach
    Abstract:

    The Campylobacter Lari group is a phylogenetic clade within the epsilon subdivision of the Proteobacteria and is part of the thermotolerant Campylobacter spp., a division within the genus that includes the human pathogen Campylobacter jejuni. The C. Lari group is currently composed of five species (C. Lari, Campylobacter insulaenigrae, Campylobacter volucris, Campylobacter subantarcticus, and Campylobacter peloridis), as well as a group of strains termed the urease-positive thermophilic Campylobacter (UPTC) and other C. Lari-like strains. Here we present the complete genome sequences of 11 C. Lari group strains, including the five C. Lari group species, four UPTC strains, and a Lari-like strain isolated in this study. The genome of C. Lari subsp. Lari strain RM2100 was described previously. Analysis of the C. Lari group genomes indicates that this group is highly related at the genome level. Furthermore, these genomes are strongly syntenic with minor rearrangements occurring only in 4 of the 12 genomes studied. The C. Lari group can be bifurcated, based on the flagella and flagellar modification genes. Genomic analysis of the UPTC strains indicated that these organisms are variable but highly similar, closely related to but distinct from C. Lari. Additionally, the C. Lari group contains multiple genes encoding hemagglutination domain proteins, which are either contingency genes or linked to conserved contingency genes. Many of the features identified in strain RM2100, such as major deficiencies in amino acid biosynthesis and energy metabolism, are conserved across all 12 genomes, suggesting that these common features may play a role in the association of the C. Lari group with coastal environments and watersheds.

  • Campylobacter volucris sp nov., isolated from black-headed gulls (Larus ridibundus)
    International Journal of Systematic and Evolutionary Microbiology, 2010
    Co-Authors: Lies Debruyne, Björn Olsen, Tina Broman, Sven Bergstrom, Peter Vandamme
    Abstract:

    During a study of the prevalence of Campylobacter jejuni in black-headed gulls (Larus ridibundus) in Sweden, three isolates, strains LMG 24379, LMG 24380T and LMG 24381, were initially identified as Campylobacter Lari. Further characterization by both AFLP and whole-cell protein SDS-PAGE analyses revealed that they formed a distinct group in the genus Campylobacter. This unique position was confirmed by phenotypic characterization, 16S rRNA and hsp60 gene sequence analysis and DNA–DNA hybridizations. The combined data confirm that these isolates represent a novel species within the genus Campylobacter, for which the name Campylobacter volucris sp. nov. is proposed. The type strain is LMG 24380T (=CCUG 57498T).

  • Campylobacter subantarcticus sp nov isolated from birds in the sub antarctic region
    International Journal of Systematic and Evolutionary Microbiology, 2010
    Co-Authors: Lies Debruyne, Tina Broman, Sven Bergstrom, Bjorn R Olsen, Peter Vandamme
    Abstract:

    Six Gram-stain-negative, spiral-shaped, microaerobic isolates were obtained during a sampling from wild birds in the sub-Antarctic region. Based on initial observations, these isolates were classified as Campylobacter Lari-like. The isolates were further characterized by whole-cell protein and amplified fragment length polymorphism (AFLP) analysis, which revealed that they were distinct from C. Lari and all other known species of the genus Campylobacter. Here, we present comprehensive phylogenetic, genomic and phenotypic evidence that these isolates represent a novel species within the genus Campylobacter, for which the name Campylobacter subantarcticus sp. nov. is proposed. The type strain is R-3023T (=LMG 24377T =CCUG 38513T).

  • Novel Campylobacter Lari-like bacteria from humans and molluscs: description of Campylobacter peloridis sp. nov., Campylobacter Lari subsp. concheus subsp. nov. and Campylobacter Lari subsp. Lari subsp. nov.
    INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY, 2009
    Co-Authors: Lies Debruyne, Evie De Brandt, Peter Vandamme
    Abstract:

    A polyphasic study was undertaken to cLarify the taxonomic position of Campylobacter Lari-like strains isolated from shellfish and humans. The diversity within the strain collection was initially screened by means of fluorescent amplified fragment length polymorphism analysis and whole-cell protein electrophoresis, revealing the existence of two clusters distinct from C. Lari and other Campylobacter species. The divergence of these clusters was confirmed by phenotypic analysis and by 16S rRNA and hsp60 gene sequence analysis. Phylogenetic analysis identified C. Lari, Campylobacter jejuni, Campylobacter coli and Campylobacter insulaenigrae as the closest phylogenetic neighbours of both taxa. DNA-DNA hybridizations revealed that one cluster, comprising 10 strains, represented a novel Campylobacter species, for which the name Campylobacter peloridis sp. nov. is proposed, with 2314BVA(T) (=LMG 23910(T) =CCUG 55787(T)) as the type strain. The second cluster, comprising six strains, represents a novel subspecies within the species C. Lari, for which the name Campylobacter Lari subsp. concheus subsp. nov. is proposed, with 2897R(T) (=LMG 21009(T) =CCUG 55786(T)) as the type strain. The description of C. Lari subsp. concheus has the effect of automatically creating the subspecies Campylobacter Lari subsp. Lari subsp. nov. (type strain LMG 8846(T)=NCTC 11352(T)).

  • rapid identification of thermotolerant Campylobacter jejuni Campylobacter coli Campylobacter Lari and Campylobacter upsaliensis from various geographic locations by a gtpase based pcr reverse hybridization assay
    Journal of Clinical Microbiology, 1999
    Co-Authors: Leenjan Van Doorn, Peter Vandamme, B A J Giesendorf, Anita Verschuurenvan Haperen, Andre P Burnens, Michael Huysmans, Martin J Blaser, Wim Quint
    Abstract:

    Recently, a gene from Campylobacter jejuni encoding a putative GTPase was identified. Based on two semiconserved GTP-binding sites encoded within this gene, PCR primers were selected that allow amplification of a 153-bp fragment from C. jejuni, C. coli, C. Lari, and C. upsaliensis. Sequence analysis of these PCR products revealed consistent interspecies variation, which allowed the definition of species-specific probes for each of the four thermotolerant Campylobacter species. Multiple probes were used to develop a line probe assay (LiPA) that permits analysis of PCR products by a single reverse hybridization step. A total of 320 reference strains and clinical isolates from various geographic origins were tested by the GTP-based PCR-LiPA. The PCR-LiPA is highly specific in comparison with conventional identification methods, including biochemical and whole-cell protein analyses. In conclusion, a simple method has been developed for rapid and highly specific identification of thermotolerant Campylobacter species.

L. Jesús Garcia-gil - One of the best experts on this subject based on the ideXlab platform.

  • A New Multiplexed Real-Time PCR Assay to Detect Campylobacter jejuni, C. coli, C. Lari, and C. upsaliensis
    Food Analytical Methods, 2010
    Co-Authors: Xavier Bonjoch, Laia Calvó, Marçal Soler, Olaya Ruiz-rueda, L. Jesús Garcia-gil
    Abstract:

    A new rapid method based on real-time PCR was developed to detect four thermophilic Campylobacter species ( Campylobacter jejuni , Campylobacter coli , Campylobacter Lari , and Campylobacter upsaliensis ) in food samples. The assay targeted the bipA gene for C. upsaliensis and C. Lari , whereas the gene encoding the ATP-binding protein CJE0832 was used to detect C. coli and C. jejuni . These genes were chosen for this assay due to their low variability and mutation rate at a species level. The multiplex PCR showed 100% inclusivity for all 25 thermophilic Campylobacter strains tested and 100% exclusivity for 38 non-targeted strains belonging to closely related species. The newly developed real-time PCR could detect down to 10^2 genomes/reaction and displayed efficiency above 97% for all species except for C. upsaliensis (90.1%). The method proved to be a reliable tool for food analysis, showing 100% sensitivity, 96% efficiency, and 92.45% specificity when validated against the gold standard method UNE-EN ISO 10272:2006 using 200 diverse food samples (meat, fish, fruits and vegetables, and raw milk). In artificially spiked samples, the detection limit of the method was 10 cfu/g in salad, 5 cfu/g in turkey meat, and 1 cfu/g in the rest of meat samples tested. Consequently, the newly designed molecular tool represents a quick and safe alternative to obtain reliable results concerning the presence/absence of the main thermophilic Campylobacter in any food sample.

Wim Quint - One of the best experts on this subject based on the ideXlab platform.

  • rapid identification of thermotolerant Campylobacter jejuni Campylobacter coli Campylobacter Lari and Campylobacter upsaliensis from various geographic locations by a gtpase based pcr reverse hybridization assay
    Journal of Clinical Microbiology, 1999
    Co-Authors: Leenjan Van Doorn, Peter Vandamme, B A J Giesendorf, Anita Verschuurenvan Haperen, Andre P Burnens, Michael Huysmans, Martin J Blaser, Wim Quint
    Abstract:

    Recently, a gene from Campylobacter jejuni encoding a putative GTPase was identified. Based on two semiconserved GTP-binding sites encoded within this gene, PCR primers were selected that allow amplification of a 153-bp fragment from C. jejuni, C. coli, C. Lari, and C. upsaliensis. Sequence analysis of these PCR products revealed consistent interspecies variation, which allowed the definition of species-specific probes for each of the four thermotolerant Campylobacter species. Multiple probes were used to develop a line probe assay (LiPA) that permits analysis of PCR products by a single reverse hybridization step. A total of 320 reference strains and clinical isolates from various geographic origins were tested by the GTP-based PCR-LiPA. The PCR-LiPA is highly specific in comparison with conventional identification methods, including biochemical and whole-cell protein analyses. In conclusion, a simple method has been developed for rapid and highly specific identification of thermotolerant Campylobacter species.

  • development of species specific dna probes for Campylobacter jejuni Campylobacter coli and Campylobacter Lari by polymerase chain reaction fingerprinting
    Journal of Clinical Microbiology, 1993
    Co-Authors: B A J Giesendorf, A Van Belkum, Ankie Koeken, H Stegeman, M H C Henkens, J Van Der Plas, Herman Goossens, H G M Niesters, Wim Quint
    Abstract:

    The application of polymerase chain reaction (PCR) fingerprinting assays enables discrimination between species and strains of microorganisms. PCR primers aiming at arbitrary sequences in combination with primers directed against the repetitive extragenic palindrome (REP) or enterobacterial repetitive intergenic consensus (ERIC) motifs generate isolate-specific DNA banding patterns. Analysis of these PCR fingerprints obtained for 33 isolates of Campylobacter jejuni, 30 isolates of Campylobacter coli, and 8 isolates of Campylobacter Lari revealed that besides generation of isolate-specific fragments, species-specific DNA fragments of identical size were synthesized. It appeared that these DNA fragments could be used as species-specific probes, since they are unique for the pattern which they are deriving from. The probes do not cross-react with amplified DNA originating from a large panel of nonrelated microorganisms. Moreover, these probes displayed species specificity, as they reacted with a single restriction fragment on Southern blots containing DNA from C. jejuni, C. coli, and C. Lari and other Campylobacter species. This combination of PCR fingerprinting and probe hybridization results in a highly specific identification assay and provides an example of specific test development without the prior need for DNA sequence information. The principle of the procedure holds great promise for the rapid isolation of DNA probes which, in combination with a general PCR assay, may lead to efficient typing and detection procedures for a multitude of medically important nonviral microorganisms.

Xianming Shi - One of the best experts on this subject based on the ideXlab platform.

  • Simultaneous Detection and Differentiation of Campylobacter jejuni , C. coli , and C. Lari in Chickens Using a Multiplex Real-Time PCR Assay
    Food Analytical Methods, 2010
    Co-Authors: Xiaomin Yao, Nereus W. Gunther, Yanping Xie, Xianming Shi
    Abstract:

    A multiplex real-time PCR (qPCR) assay was developed for simultaneous detection and differentiation of the three most important Campylobacter species in chickens. Three novel sets of PCR primers and TaqMan probes were designed to amplify the unique DNA sequences within the hipO, cdtA, and pepT genes which are specific to Campylobacter jejuni, Campylobacter coli, and Campylobacter Lari, respectively. To avoid competition in the multiple target amplifications, the concentrations of primers and probes were optimized. By using the optimized qPCR conditions together with a minor-groove binding probe of pepT, amplification efficiency greater than 92% and detection sensitivity of 38 genome copies/reaction have been achieved for all three targets. The assay was highly specific for C. jejuni, C. coli, and C. Lari with testing of 33 Campylobacter strains and 20 non-Campylobacter strains. In chicken samples spiked with known quantities of Campylobacter cells, the assay was able to detect 1 CFU/g after a 24-h enrichment. Application of the assay in food was further evaluated using 21 fresh chicken samples obtained from local supermarkets. The results revealed that, after a 24-h or 48-h enrichment, 14 samples (66.7%) were positive for C. jejuni, five samples (23.8%) were positive for C. coli, and none of the samples was contaminated by C. Lari. Taken together, the multiplex qPCR assay combined with an enrichment step is a sensitive, species-specific, and non-labor-intensive method suitable for rapid detection of C. jejuni, C. coli, and C. Lari in chicken samples.