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Martin J. Blaser - One of the best experts on this subject based on the ideXlab platform.
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An Outbreak of Gastroenteritis due to Campylobacter jejuni and Thermotolerant Campylobacter Fetus subsp Fetus
2017Co-Authors: Bruce S. Klein, Martin J. Blaser, James M. Vergeront, Paul Edmonds, Don J. Brenner, David A. Janssen, Jeffrey P. DavisAbstract:Raw milk is identified with increasing numbers of outbreaks of gastroenteritis and is an important vehicle for transmission of Campylobacter infection. Unlike Campylobacter jejuni, Campylobacter Fetus subsp Fetus has not been associated with common-source outbreaks of gastroenteritis. This report describes an outbreak of gastroenteritis involving C jejuni and a thermotolerant strain of C Fetus subsp Fetus associated with raw milk. Fifteen (39%) of 38 persons who attended a banquet in Wisconsin in June 1982 developed acute gastroenteritis. Stool specimens were obtained from nine ill guests; four yielded C jejuni and three yielded C Fetus subsp Fetus. The C Fetus subsp Fetus isolates were identified fortuitously, in part because of unusual thermotolerance (growth at 42 \s=deg\C),permitting isolation at temperature appropriate for C jejuni. Survey results implicated raw milk as the source of the outbreak. Findings provide evidence of a potentially emergent milkborne pathogen contributing to the risk of raw milk consumption and suggest that current diagnostic laboratory techniques may fail to identify significant foodborne agents.
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Campylobacter Fetus infections in humans exposure and disease
Clinical Infectious Diseases, 2014Co-Authors: Jaap A. Wagenaar, Martin J. Blaser, Marcel A. P. Van Bergen, Robert V. Tauxe, D G Newell, Jos P M Van PuttenAbstract:Campylobacter Fetus can cause intestinal illness and, occasionally, severe systemic infections. Infections mainly affect persons at higher risk, including elderly and immunocompromised individuals and those with occupational exposure to infected animals. Outbreaks are infrequent but have provided insight into sources. Source attribution of sporadic cases through case-control interviews has not been reported. The reservoirs for C. Fetus are mainly cattle and sheep. Products from these animals are suspected as sources for human infections. Campylobacter Fetus is rarely isolated from food, albeit selective isolation methods used in food microbiology are not suited for its detection. We hypothesize that the general population is regularly exposed to C. Fetus through foods of animal origin, cross-contaminated foodstuffs, and perhaps other, as yet unidentified, routes. Campylobacter Fetus infection should be suspected particularly in patients with nonspecific febrile illness who are immunocompromised or who may have been occupationally exposed to ruminants.
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complete genome sequence of Campylobacter Fetus subsp testudinum strain 03 427t
Genome Announcements, 2013Co-Authors: Maarten J. Gilbert, Jaap A. Wagenaar, Martin J. Blaser, William G. Miller, Emma Yee, Birgitta DuimAbstract:ABSTRACT Campylobacter Fetus subsp. testudinum has been isolated from reptiles and humans. This Campylobacter subspecies is genetically distinct from other C. Fetus subspecies. Here, we present the first whole-genome sequence for this C. Fetus subspecies.
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human infections with new subspecies of Campylobacter Fetus
Emerging Infectious Diseases, 2013Co-Authors: Mary E. Patrick, Jaap A. Wagenaar, Martin J. Blaser, Maarten J. Gilbert, Robert V. Tauxe, Collette FitzgeraldAbstract:Campylobacter Fetus subsp. testudinum subsp. nov. is a newly proposed subspecies of C. Fetus with markers of reptile origin. We summarize epidemiologic information for 9 humans infected with this bacterium. All cases were in men, most of whom were of Asian origin. Infection might have been related to exposure to Asian foods or reptiles.
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Genetic Relationships among Reptilian and Mammalian Campylobacter Fetus Strains Determined by Multilocus Sequence Typing
Journal of Clinical Microbiology, 2010Co-Authors: Kate E. Dingle, Martin J. Blaser, Janet M. Pruckler, Collette Fitzgerald, Marcel A. P. Van Bergen, Andrew J. Lawson, Robert J. Owen, Jaap A. WagenaarAbstract:Reptile Campylobacter Fetus isolates and closely related strains causing human disease were characterized by multilocus sequence typing. They shared ∼90% nucleotide sequence identity with classical mammalian C. Fetus, and there was evidence of recombination among members of these two groups. The reptile group represents a possible separate genomospecies capable of infecting humans.
Jaap A. Wagenaar - One of the best experts on this subject based on the ideXlab platform.
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homologous recombination between genetically divergent Campylobacter Fetus lineages supports host associated speciation
Genome Biology and Evolution, 2018Co-Authors: Maarten J. Gilbert, Jaap A. Wagenaar, Birgitta Duim, Linda Van Der Graafvan Bloois, Aldert ZomerAbstract:Homologous recombination is a major driver of bacterial speciation. Genetic divergence and host association are important factors influencing homologous recombination. Here, we study these factors for Campylobacter Fetus, which shows a distinct intraspecific host dichotomy. Campylobacter Fetus subspecies Fetus (Cff) and venerealis are associated with mammals, whereas C. Fetus subsp. testudinum (Cft) is associated with reptiles. Recombination between these genetically divergent C. Fetus lineages is extremely rare. Previously it was impossible to show whether this barrier to recombination was determined by the differential host preferences, by the genetic divergence between both lineages or by other factors influencing recombination, such as restriction-modification, CRISPR/Cas, and transformation systems. Fortuitously, a distinct C. Fetus lineage (ST69) was found, which was highly related to mammal-associated C. Fetus, yet isolated from a chelonian. The whole genome sequences of two C. Fetus ST69 isolates were compared with those of mammal- and reptile-associated C. Fetus strains for phylogenetic and recombination analysis. In total, 5.1-5.5% of the core genome of both ST69 isolates showed signs of recombination. Of the predicted recombination regions, 80.4% were most closely related to Cft, 14.3% to Cff, and 5.6% to C. iguaniorum. Recombination from C. Fetus ST69 to Cft was also detected, but to a lesser extent and only in chelonian-associated Cft strains. This study shows that despite substantial genetic divergence no absolute barrier to homologous recombination exists between two distinct C. Fetus lineages when occurring in the same host type, which provides valuable insights in bacterial speciation and evolution.
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Comparative Genomics of Campylobacter Fetus from Reptiles and Mammals Reveals Divergent Evolution in Host-Associated Lineages
Genome biology and evolution, 2016Co-Authors: Maarten J. Gilbert, Collette Fitzgerald, William G. Miller, Emma Yee, Aldert Zomer, Linda Van Der Graaf-van Bloois, Ken J. Forbes, Guillaume Méric, Samuel K. Sheppard, Jaap A. WagenaarAbstract:Campylobacter Fetus currently comprises three recognized subspecies, which display distinct host association. Campylobacter Fetus subsp. Fetus and C Fetus subsp. venerealis are both associated with endothermic mammals, primarily ruminants, whereas C Fetus subsp. testudinum is primarily associated with ectothermic reptiles. Both C. Fetus subsp. testudinum and C. Fetus subsp. Fetus have been associated with severe infections, often with a systemic component, in immunocompromised humans. To study the genetic factors associated with the distinct host dichotomy in C. Fetus, whole-genome sequencing and comparison of mammal- and reptile-associated C Fetus was performed. The genomes of C Fetus subsp. testudinum isolated from either reptiles or humans were compared with elucidate the genetic factors associated with pathogenicity in humans. Genomic comparisons showed conservation of gene content and organization among C Fetus subspecies, but a clear distinction between mammal- and reptile-associated C Fetus was observed. Several genomic regions appeared to be subspecies specific, including a putative tricarballylate catabolism pathway, exclusively present in C Fetus subsp. testudinum strains. Within C Fetus subsp. testudinum, sapA, sapB, and sapAB type strains were observed. The recombinant locus iamABC (mlaFED) was exclusively associated with invasive C Fetus subsp. testudinum strains isolated from humans. A phylogenetic reconstruction was consistent with divergent evolution in host-associated strains and the existence of a barrier to lateral gene transfer between mammal- and reptile-associated C Fetus Overall, this study shows that reptile-associated C Fetus subsp. testudinum is genetically divergent from mammal-associated C Fetus subspecies.
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first closed genome sequence of Campylobacter Fetus subsp venerealis bv intermedius
Genome Announcements, 2014Co-Authors: Linda Van Der Graafvan Bloois, Jaap A. Wagenaar, William G. Miller, Emma Yee, James L Bono, Martine Rijnsburger, C M Campero, Birgitta DuimAbstract:Campylobacter Fetus subsp. venerealis bv. intermedius is a variant of C. Fetus subsp. venerealis, the causative agent of bovine genital Campylobacteriosis, a venereal disease associated with abortion and infertility in cattle. We report the first closed whole-genome sequence of this biovar.
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Campylobacter Fetus infections in humans exposure and disease
Clinical Infectious Diseases, 2014Co-Authors: Jaap A. Wagenaar, Martin J. Blaser, Marcel A. P. Van Bergen, Robert V. Tauxe, D G Newell, Jos P M Van PuttenAbstract:Campylobacter Fetus can cause intestinal illness and, occasionally, severe systemic infections. Infections mainly affect persons at higher risk, including elderly and immunocompromised individuals and those with occupational exposure to infected animals. Outbreaks are infrequent but have provided insight into sources. Source attribution of sporadic cases through case-control interviews has not been reported. The reservoirs for C. Fetus are mainly cattle and sheep. Products from these animals are suspected as sources for human infections. Campylobacter Fetus is rarely isolated from food, albeit selective isolation methods used in food microbiology are not suited for its detection. We hypothesize that the general population is regularly exposed to C. Fetus through foods of animal origin, cross-contaminated foodstuffs, and perhaps other, as yet unidentified, routes. Campylobacter Fetus infection should be suspected particularly in patients with nonspecific febrile illness who are immunocompromised or who may have been occupationally exposed to ruminants.
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complete genome sequence of Campylobacter Fetus subsp testudinum strain 03 427t
Genome Announcements, 2013Co-Authors: Maarten J. Gilbert, Jaap A. Wagenaar, Martin J. Blaser, William G. Miller, Emma Yee, Birgitta DuimAbstract:ABSTRACT Campylobacter Fetus subsp. testudinum has been isolated from reptiles and humans. This Campylobacter subspecies is genetically distinct from other C. Fetus subspecies. Here, we present the first whole-genome sequence for this C. Fetus subspecies.
Gregorio Iraola - One of the best experts on this subject based on the ideXlab platform.
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accurate and fast identification of Campylobacter Fetus in bulls by real time pcr targeting a 16s rrna gene sequence
Veterinary and Animal Science, 2021Co-Authors: Rafael Delpiazzo, Maila Barcellos, Martin Fraga, Gregorio Iraola, Sofia Barros, Laura Betancor, J Gil, Claudia MorsellaAbstract:Campylobacter Fetus is an important animal pathogen that causes infectious infertility, embryonic mortality and abortions in cattle and sheep flocks. There are two recognized subspecies related with reproductive disorders in livestock: Campylobacter Fetus subsp. Fetus (Cff) and Campylobacter Fetus subsp. venerealis (Cfv). Rapid and reliable detection of this pathogenic species in bulls is of upmost importance for disease control in dairy and beef herds as they are asymptomatic carriers. The aim of the present work was to assess the performance a real-time PCR (qPCR) method for the diagnosis of Campylobacter Fetus in samples from bulls, comparing it with culture and isolation methods. 520 preputial samples were both cultured in Skirrow's medium and analyzed by qPCR. The estimated sensitivity of qPCR was 90.9% (95% CI, 69.4%–100%), and the specificity was 99.4% (95% CI, 98.6% - 100%). The proportion of C. Fetus positive individuals was 2.1% by isolation and 2.5% by qPCR. Isolates were identified by biochemical tests as Cfv (n = 9) and Cff (n = 2). Our findings support the use of qPCR for fast and accurate detection of C. Fetus directly from field samples of preputial smegma of bulls. The qPCR method showed to be suitable for massive screenings because it can be performed in pooled samples without losing accuracy and sensitivity.
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distinct Campylobacter Fetus lineages adapted as livestock pathogens and human pathobionts in the intestinal microbiota
Nature Communications, 2017Co-Authors: Philippe Lehours, Gregorio Iraola, Samuel C. Forster, Nitin Kumar, Sadjia Bekal, Francisco Javier GarciapenaAbstract:Campylobacter Fetus is a venereal pathogen of cattle and sheep, and an opportunistic human pathogen. It is often assumed that C. Fetus infection occurs in humans as a zoonosis through food chain transmission. Here we show that mammalian C. Fetus consists of distinct evolutionary lineages, primarily associated with either human or bovine hosts. We use whole-genome phylogenetics on 182 strains from 17 countries to provide evidence that C. Fetus may have originated in humans around 10,500 years ago and may have "jumped" into cattle during the livestock domestication period. We detect C. Fetus genomes in 8% of healthy human fecal metagenomes, where the human-associated lineages are the dominant type (78%). Thus, our work suggests that C. Fetus is an unappreciated human intestinal pathobiont likely spread by human to human transmission. This genome-based evolutionary framework will facilitate C. Fetus epidemiology research and the development of improved molecular diagnostics and prevention schemes for this neglected pathogen.
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assessing the intra species genetic variability in the clonal pathogen Campylobacter Fetus crisprs are highly polymorphic dna markers
Journal of Microbiological Methods, 2017Co-Authors: Lucia Calleros, Claudia Morsella, Gregorio Iraola, Laura Betancor, Alejandra Mendez, Fernando Alberto Paolicchi, Silvia Silveyra, Alejandra Velilla, Ruben PerezAbstract:Campylobacter Fetus is a Gram-negative, microaerophilic bacterium that infects animals and humans. The subspecies Campylobacter Fetus subsp. Fetus (Cff) affects a broad range of vertebrate hosts and induces abortion in cows and sheep. Campylobacter Fetus subsp. venerealis (Cfv) is restricted to cattle and causes the endemic disease bovine genital Campylobacteriosis, which triggers reproductive problems and is responsible for major economic losses. Campylobacter Fetus subsp. testudinum (Cft) has been isolated mostly from apparently healthy reptiles belonging to different species but also from ill snakes and humans. Genotypic differentiation of Cff and Cfv is difficult, and epidemiological information is scarce because there are few methods to study the genetic diversity of the strains. We analyze the efficacy of MLST, ribosomal sequences (23S gene and internal spacer region), and CRISPRs to assess the genetic variability of C. Fetus in bovine and human isolates. Sequences retrieved from complete genomes were included in the analysis for comparative purposes. MLST and ribosomal sequences had scarce or null variability, while the CRISPR-cas system structure and the sequence of CRISPR1 locus showed remarkable diversity. None of the sequences here analyzed provided evidence of a genetic differentiation of Cff and Cfv in bovine isolates. Comparison of bovine and human isolates with Cft strains showed a striking divergence. Inter-host differences raise the possibility of determining the original host of human infections using CRISPR sequences. CRISPRs are the most variable sequences analyzed in C. Fetus so far, and constitute excellent representatives of a dynamic fraction of the genome. CRISPR typing is a promising tool to characterize isolates and to track the source and transmission route of C. Fetus infections.
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Distinct Campylobacter Fetus lineages adapted as livestock pathogens and human pathobionts in the intestinal microbiota
Nature Publishing Group, 2017Co-Authors: Gregorio Iraola, Philippe Lehours, Helmut Hotzel, Claudia Morsella, Fernando Paolicchi, Samuel C. Forster, Nitin Kumar, Sadjia Bekal, Francisco J. García-peña, Po-ren HsuehAbstract:Human infections with Campylobacter Fetus are often assumed to be derived from livestock. Here, Iraola et al. provide evidence that healthy humans may act as carriers and dispersers, and C. Fetus may have originated in humans as an intestinal pathobiont and then adapted as a livestock pathogen
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a novel real time pcr assay for quantitative detection of Campylobacter Fetus based on ribosomal sequences
BMC Veterinary Research, 2016Co-Authors: Gregorio Iraola, Ruben Perez, Claudia Morsella, Laura Betancor, Alejandra Mendez, Fernando Alberto Paolicchi, Ana Marandino, Alessandra Piccirillo, Gonzalo Tomas, Alejandra VelillaAbstract:Campylobacter Fetus is a pathogen of major concern for animal and human health. The species shows a great intraspecific variation, with three subspecies: C. Fetus subsp. Fetus, C. Fetus subsp. venerealis, and C. Fetus subsp. testudinum. Campylobacter Fetus Fetus affects a broad range of hosts and induces abortion in sheep and cows. Campylobacter Fetus venerealis is restricted to cattle and causes the endemic disease bovine genital Campylobacteriosis, which triggers reproductive problems and is responsible for major economic losses. Campylobacter Fetus testudinum has been proposed recently based on genetically divergent strains isolated from reptiles and humans. Both C. Fetus Fetus and C. Fetus testudinum are opportunistic pathogens for immune-compromised humans. Biochemical tests remain as the gold standard for identifying C. Fetus but the fastidious growing requirements and the lack of reliability and reproducibility of some biochemical tests motivated the development of molecular diagnostic tools. These methods have been successfully tested on bovine isolates but fail to detect some genetically divergent strains isolated from other hosts. The aim of the present study was to develop a highly specific molecular assay to identify and quantify C. Fetus strains. We developed a highly sensitive real-time PCR assay that targets a unique region of the 16S rRNA gene. This assay successfully detected all C. Fetus strains, including those that were negative for the cstA gene-based assay used as a standard for molecular C. Fetus identification. The assay showed high specificity and absence of cross-reactivity with other bacterial species. The analytical testing of the assay was determined using a standard curve. The assay demonstrated a wide dynamic range between 102 and 107 genome copies per reaction, and a good reproducibility with small intra- and inter-assay variability. The possibility to characterize samples in a rapid, sensitive and reproducible way makes this assay a good option to establish a new standard in molecular identification and quantification of C. Fetus species.
Maarten J. Gilbert - One of the best experts on this subject based on the ideXlab platform.
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homologous recombination between genetically divergent Campylobacter Fetus lineages supports host associated speciation
Genome Biology and Evolution, 2018Co-Authors: Maarten J. Gilbert, Jaap A. Wagenaar, Birgitta Duim, Linda Van Der Graafvan Bloois, Aldert ZomerAbstract:Homologous recombination is a major driver of bacterial speciation. Genetic divergence and host association are important factors influencing homologous recombination. Here, we study these factors for Campylobacter Fetus, which shows a distinct intraspecific host dichotomy. Campylobacter Fetus subspecies Fetus (Cff) and venerealis are associated with mammals, whereas C. Fetus subsp. testudinum (Cft) is associated with reptiles. Recombination between these genetically divergent C. Fetus lineages is extremely rare. Previously it was impossible to show whether this barrier to recombination was determined by the differential host preferences, by the genetic divergence between both lineages or by other factors influencing recombination, such as restriction-modification, CRISPR/Cas, and transformation systems. Fortuitously, a distinct C. Fetus lineage (ST69) was found, which was highly related to mammal-associated C. Fetus, yet isolated from a chelonian. The whole genome sequences of two C. Fetus ST69 isolates were compared with those of mammal- and reptile-associated C. Fetus strains for phylogenetic and recombination analysis. In total, 5.1-5.5% of the core genome of both ST69 isolates showed signs of recombination. Of the predicted recombination regions, 80.4% were most closely related to Cft, 14.3% to Cff, and 5.6% to C. iguaniorum. Recombination from C. Fetus ST69 to Cft was also detected, but to a lesser extent and only in chelonian-associated Cft strains. This study shows that despite substantial genetic divergence no absolute barrier to homologous recombination exists between two distinct C. Fetus lineages when occurring in the same host type, which provides valuable insights in bacterial speciation and evolution.
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Comparative Genomics of Campylobacter Fetus from Reptiles and Mammals Reveals Divergent Evolution in Host-Associated Lineages
Genome biology and evolution, 2016Co-Authors: Maarten J. Gilbert, Collette Fitzgerald, William G. Miller, Emma Yee, Aldert Zomer, Linda Van Der Graaf-van Bloois, Ken J. Forbes, Guillaume Méric, Samuel K. Sheppard, Jaap A. WagenaarAbstract:Campylobacter Fetus currently comprises three recognized subspecies, which display distinct host association. Campylobacter Fetus subsp. Fetus and C Fetus subsp. venerealis are both associated with endothermic mammals, primarily ruminants, whereas C Fetus subsp. testudinum is primarily associated with ectothermic reptiles. Both C. Fetus subsp. testudinum and C. Fetus subsp. Fetus have been associated with severe infections, often with a systemic component, in immunocompromised humans. To study the genetic factors associated with the distinct host dichotomy in C. Fetus, whole-genome sequencing and comparison of mammal- and reptile-associated C Fetus was performed. The genomes of C Fetus subsp. testudinum isolated from either reptiles or humans were compared with elucidate the genetic factors associated with pathogenicity in humans. Genomic comparisons showed conservation of gene content and organization among C Fetus subspecies, but a clear distinction between mammal- and reptile-associated C Fetus was observed. Several genomic regions appeared to be subspecies specific, including a putative tricarballylate catabolism pathway, exclusively present in C Fetus subsp. testudinum strains. Within C Fetus subsp. testudinum, sapA, sapB, and sapAB type strains were observed. The recombinant locus iamABC (mlaFED) was exclusively associated with invasive C Fetus subsp. testudinum strains isolated from humans. A phylogenetic reconstruction was consistent with divergent evolution in host-associated strains and the existence of a barrier to lateral gene transfer between mammal- and reptile-associated C Fetus Overall, this study shows that reptile-associated C Fetus subsp. testudinum is genetically divergent from mammal-associated C Fetus subspecies.
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Campylobacter Fetus subsp testudinum subsp nov isolated from humans and reptiles
International Journal of Systematic and Evolutionary Microbiology, 2014Co-Authors: Collette Fitzgerald, Janet M. Pruckler, Marcel A. P. Van Bergen, Maarten J. Gilbert, Mary E. Patrick, Tracy Stiles, Andy J Lawson, Monica Santovenia, Kevin Joyce, Steven StroikaAbstract:A polyphasic study was undertaken to determine the taxonomic position of 13 Campylobacter Fetus -like strains from humans (n = 8) and reptiles (n = 5). The results of matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) MS and genomic data from sap analysis, 16S rRNA gene and hsp60 sequence comparison, pulsed-field gel electrophoresis, amplified fragment length polymorphism analysis, DNA–DNA hybridization and whole genome sequencing demonstrated that these strains are closely related to C. Fetus but clearly differentiated from recognized subspecies of C. Fetus . Therefore, this unique cluster of 13 strains represents a novel subspecies within the species C. Fetus , for which the name Campylobacter Fetus subsp. testudinum subsp. nov. is proposed, with strain 03-427T ( = ATCC BAA-2539T = LMG 27499T) as the type strain. Although this novel taxon could not be differentiated from C. Fetus subsp. Fetus and C. Fetus subsp. venerealis using conventional phenotypic tests, MALDI-TOF MS revealed the presence of multiple phenotypic biomarkers which distinguish Campylobacter Fetus subsp. testudinum subsp. nov. from recognized subspecies of C. Fetus .
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complete genome sequence of Campylobacter Fetus subsp testudinum strain 03 427t
Genome Announcements, 2013Co-Authors: Maarten J. Gilbert, Jaap A. Wagenaar, Martin J. Blaser, William G. Miller, Emma Yee, Birgitta DuimAbstract:ABSTRACT Campylobacter Fetus subsp. testudinum has been isolated from reptiles and humans. This Campylobacter subspecies is genetically distinct from other C. Fetus subspecies. Here, we present the first whole-genome sequence for this C. Fetus subspecies.
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human infections with new subspecies of Campylobacter Fetus
Emerging Infectious Diseases, 2013Co-Authors: Mary E. Patrick, Jaap A. Wagenaar, Martin J. Blaser, Maarten J. Gilbert, Robert V. Tauxe, Collette FitzgeraldAbstract:Campylobacter Fetus subsp. testudinum subsp. nov. is a newly proposed subspecies of C. Fetus with markers of reptile origin. We summarize epidemiologic information for 9 humans infected with this bacterium. All cases were in men, most of whom were of Asian origin. Infection might have been related to exposure to Asian foods or reptiles.
Collette Fitzgerald - One of the best experts on this subject based on the ideXlab platform.
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Comparative Genomics of Campylobacter Fetus from Reptiles and Mammals Reveals Divergent Evolution in Host-Associated Lineages
Genome biology and evolution, 2016Co-Authors: Maarten J. Gilbert, Collette Fitzgerald, William G. Miller, Emma Yee, Aldert Zomer, Linda Van Der Graaf-van Bloois, Ken J. Forbes, Guillaume Méric, Samuel K. Sheppard, Jaap A. WagenaarAbstract:Campylobacter Fetus currently comprises three recognized subspecies, which display distinct host association. Campylobacter Fetus subsp. Fetus and C Fetus subsp. venerealis are both associated with endothermic mammals, primarily ruminants, whereas C Fetus subsp. testudinum is primarily associated with ectothermic reptiles. Both C. Fetus subsp. testudinum and C. Fetus subsp. Fetus have been associated with severe infections, often with a systemic component, in immunocompromised humans. To study the genetic factors associated with the distinct host dichotomy in C. Fetus, whole-genome sequencing and comparison of mammal- and reptile-associated C Fetus was performed. The genomes of C Fetus subsp. testudinum isolated from either reptiles or humans were compared with elucidate the genetic factors associated with pathogenicity in humans. Genomic comparisons showed conservation of gene content and organization among C Fetus subspecies, but a clear distinction between mammal- and reptile-associated C Fetus was observed. Several genomic regions appeared to be subspecies specific, including a putative tricarballylate catabolism pathway, exclusively present in C Fetus subsp. testudinum strains. Within C Fetus subsp. testudinum, sapA, sapB, and sapAB type strains were observed. The recombinant locus iamABC (mlaFED) was exclusively associated with invasive C Fetus subsp. testudinum strains isolated from humans. A phylogenetic reconstruction was consistent with divergent evolution in host-associated strains and the existence of a barrier to lateral gene transfer between mammal- and reptile-associated C Fetus Overall, this study shows that reptile-associated C Fetus subsp. testudinum is genetically divergent from mammal-associated C Fetus subspecies.
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Campylobacter Fetus subsp testudinum subsp nov isolated from humans and reptiles
International Journal of Systematic and Evolutionary Microbiology, 2014Co-Authors: Collette Fitzgerald, Janet M. Pruckler, Marcel A. P. Van Bergen, Maarten J. Gilbert, Mary E. Patrick, Tracy Stiles, Andy J Lawson, Monica Santovenia, Kevin Joyce, Steven StroikaAbstract:A polyphasic study was undertaken to determine the taxonomic position of 13 Campylobacter Fetus -like strains from humans (n = 8) and reptiles (n = 5). The results of matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) MS and genomic data from sap analysis, 16S rRNA gene and hsp60 sequence comparison, pulsed-field gel electrophoresis, amplified fragment length polymorphism analysis, DNA–DNA hybridization and whole genome sequencing demonstrated that these strains are closely related to C. Fetus but clearly differentiated from recognized subspecies of C. Fetus . Therefore, this unique cluster of 13 strains represents a novel subspecies within the species C. Fetus , for which the name Campylobacter Fetus subsp. testudinum subsp. nov. is proposed, with strain 03-427T ( = ATCC BAA-2539T = LMG 27499T) as the type strain. Although this novel taxon could not be differentiated from C. Fetus subsp. Fetus and C. Fetus subsp. venerealis using conventional phenotypic tests, MALDI-TOF MS revealed the presence of multiple phenotypic biomarkers which distinguish Campylobacter Fetus subsp. testudinum subsp. nov. from recognized subspecies of C. Fetus .
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human infections with new subspecies of Campylobacter Fetus
Emerging Infectious Diseases, 2013Co-Authors: Mary E. Patrick, Jaap A. Wagenaar, Martin J. Blaser, Maarten J. Gilbert, Robert V. Tauxe, Collette FitzgeraldAbstract:Campylobacter Fetus subsp. testudinum subsp. nov. is a newly proposed subspecies of C. Fetus with markers of reptile origin. We summarize epidemiologic information for 9 humans infected with this bacterium. All cases were in men, most of whom were of Asian origin. Infection might have been related to exposure to Asian foods or reptiles.
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Genetic Relationships among Reptilian and Mammalian Campylobacter Fetus Strains Determined by Multilocus Sequence Typing
Journal of Clinical Microbiology, 2010Co-Authors: Kate E. Dingle, Martin J. Blaser, Janet M. Pruckler, Collette Fitzgerald, Marcel A. P. Van Bergen, Andrew J. Lawson, Robert J. Owen, Jaap A. WagenaarAbstract:Reptile Campylobacter Fetus isolates and closely related strains causing human disease were characterized by multilocus sequence typing. They shared ∼90% nucleotide sequence identity with classical mammalian C. Fetus, and there was evidence of recombination among members of these two groups. The reptile group represents a possible separate genomospecies capable of infecting humans.