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Cold Spring Harbor Perspectives in... Jun 2015The global significance of Campylobacter jejuni and Campylobacter coli as gastrointestinal human pathogens has motivated numerous studies to characterize their... (Review)
Review
The global significance of Campylobacter jejuni and Campylobacter coli as gastrointestinal human pathogens has motivated numerous studies to characterize their population biology and evolution. These bacteria are a common component of the intestinal microbiota of numerous bird and mammal species and cause disease in humans, typically via consumption of contaminated meat products, especially poultry meat. Sequence-based molecular typing methods, such as multilocus sequence typing (MLST) and whole genome sequencing (WGS), have been instructive for understanding the epidemiology and evolution of these bacteria and how phenotypic variation relates to the high degree of genetic structuring in C. coli and C. jejuni populations. Here, we describe aspects of the relatively short history of coevolution between humans and pathogenic Campylobacter, by reviewing research investigating how mutation and lateral or horizontal gene transfer (LGT or HGT, respectively) interact to create the observed population structure. These genetic changes occur in a complex fitness landscape with divergent ecologies, including multiple host species, which can lead to rapid adaptation, for example, through frame-shift mutations that alter gene expression or the acquisition of novel genetic elements by HGT. Recombination is a particularly strong evolutionary force in Campylobacter, leading to the emergence of new lineages and even large-scale genome-wide interspecies introgression between C. jejuni and C. coli. The increasing availability of large genome datasets is enhancing understanding of Campylobacter evolution through the application of methods, such as genome-wide association studies, but MLST-derived clonal complex designations remain a useful method for describing population structure.
Topics: Adaptation, Physiological; Campylobacter coli; Campylobacter jejuni; Evolution, Molecular; Recombination, Genetic
PubMed: 26101080
DOI: 10.1101/cshperspect.a018119 -
MSphere May 2021Previous studies indicated that has developed several mechanisms that confer resistance to florfenicol, which is used in food animal production. This study describes...
Previous studies indicated that has developed several mechanisms that confer resistance to florfenicol, which is used in food animal production. This study describes the coexistence of and in and isolates from pigs and poultry. Moreover, whole-genome sequencing data showed that the two genes are located in various multidrug resistance genomic islands within different regions of the genomes. The emergence of and may support the spread of florfenicol-resistant strains of animal origin. Florfenicol is widely used for the treatment of respiratory infections and as a feed additive in food animal production. As a foodborne pathogen, is constantly exposed to florfenicol, and resistance to this antimicrobial agent has increased in recent years. Previous studies indicated that has developed several mechanisms that confer resistance to florfenicol. This study describes for the first time the coexistence of the florfenicol exporter FexA and the ribosomal protective protein OptrA in isolated from pigs. The two genes were located in various multidrug resistance genomic islands within different regions of the genomes. Although phenicols are not commonly used for the treatment of infections, the extensive use of florfenicol in food animals may play a role in the coselection of multidrug resistance genomic island (MDRGI)-carrying isolates which also exhibited resistance to critically important antimicrobial agents (macrolides, aminoglycosides, and tetracyclines) commonly used for the treatment of human campylobacteriosis.
Topics: Animals; Anti-Bacterial Agents; Bacterial Proteins; Campylobacter Infections; Campylobacter coli; Campylobacter jejuni; Drug Resistance, Multiple, Bacterial; Genomic Islands; Poultry; Swine; Thiamphenicol
PubMed: 33980673
DOI: 10.1128/mSphere.00125-21 -
The Science of the Total Environment Sep 2023Campylobacter spp. is one of the most frequent pathogens of bacterial gastroenteritis recorded worldwide. Campylobacter jejuni (C. jejuni) and Campylobacter coli (C....
Campylobacter spp. is one of the most frequent pathogens of bacterial gastroenteritis recorded worldwide. Campylobacter jejuni (C. jejuni) and Campylobacter coli (C. coli) are the two major disease-associated species, accounting for >95 % of infections, and thus have been selected for disease surveillance. Monitoring temporal variations in pathogen concentration and diversity excreted from community wastewater allows the early detection of outbreaks. Multiplex real-time/quantitative PCR (qPCR) enables multi-target quantification of pathogens in various types of samples including wastewater. Also, an internal amplification control (IAC) is required for each sample when adopting PCR-based methods for pathogen detection and quantification in wastewater to exclude the inhibition of the wastewater matrix. To achieve reliable quantification of C. jejuni and C. coli towards wastewater samples, this study developed and optimized a triplex qPCR assay by combining three qPCR primer-probe sets targeting Campylobacter jejuni subsp. jejuni, Campylobacter coli, and Campylobacter sputorum biovar sputorum (C. sputorum), respectively. This triplex qPCR assay not only can directly and simultaneously detect the concentration of C. jejuni and C. coli in wastewater but also can achieve the PCR inhibition control using C. sputorum primer-probe set. This is the first developed triplex qPCR assay with IAC for C. jejuni and C. coli, to be used in the wastewater-based epidemiology (WBE) applications. The optimized triplex qPCR assay enables the detection limit of the assay (ALOD and wastewater (PLOD) as 10 gene copy/μL and 2 log10 cells/mL (2 gene copies/μL of extracted DNA), respectively. The application of this triplex qPCR to 52 real raw wastewater samples from 13 wastewater treatment plants demonstrated its potential as a high-throughput and economically viable tool for the long-term monitoring of C. jejuni and C. coli prevalence in communities and the surrounding environments. This study provided an accessible methodology and a solid foundation for WBE-based monitoring of Campylobacter spp. relevant diseases and paved the road for future WBE back-estimation of C. jejuni and C. coli prevalence.
Topics: Campylobacter jejuni; Campylobacter coli; Wastewater; Sensitivity and Specificity; Campylobacter; DNA, Bacterial
PubMed: 37268129
DOI: 10.1016/j.scitotenv.2023.164574 -
Brazilian Journal of Microbiology :... Jun 2021Campylobacter spp. have been a predominant cause of bacterial foodborne gastroenteritis worldwide, causing substantial costs to public healthcare systems. This study...
Campylobacter spp. have been a predominant cause of bacterial foodborne gastroenteritis worldwide, causing substantial costs to public healthcare systems. This study aimed to assess the invasion and pro-inflammatory cytokine production capacity of Campylobacter coli strains isolated in Brazil. A total of 50 C. coli isolated from different sources in Brazil were analyzed for their capacity of invasion in Caco-2 and U-937 cell lines. The production of pro-inflammatory cytokines was quantitatively measured in response to C. coli. All the strains studied showed invasion percentage ≥ 40% in polarized Caco-2 cells. In U-937 cells assay, 35 of 50 C. coli strains studied showed invasion percentage ≥ 50%. A significant increase in IL-8 production by infected U-937 cells was observed for 17.5% of the C. coli isolates. The high percentages of invasion in Caco-2 and U-937 cells observed for all studied strains, plus the increased production of IL-8 by U-937 cells against some strains, highlighted the pathogenic potential of the C. coli studied and bring extremely relevant data since it has never been reported for strains isolated in Brazil and there are a few data for C. coli in the literature.
Topics: Brazil; Caco-2 Cells; Campylobacter coli; Cytokines; Epithelial Cells; Humans; Interleukin-8; Phagocytes; U937 Cells
PubMed: 33590448
DOI: 10.1007/s42770-021-00450-1 -
BMC Microbiology Apr 2023Campylobacter species are the major cause of bacterial gastroenteritis. As there is no effective vaccine, combined with the rapid increase in antimicrobial resistant...
Campylobacter species are the major cause of bacterial gastroenteritis. As there is no effective vaccine, combined with the rapid increase in antimicrobial resistant strains, there is a need to identify new targets for intervention. Essential genes are those that are necessary for growth and/or survival, making these attractive targets. In this study, comprehensive transposon mutant libraries were created in six C. jejuni strains, four C. coli strains and one C. lari and C. hyointestinalis strain, allowing for those genes that cannot tolerate a transposon insertion being called as essential. Comparison of essential gene lists using core genome analysis can highlight those genes which are common across multiple strains and/or species. Comparison of C. jejuni and C. coli, the two species that cause the most disease, identified 316 essential genes. Genes of interest highlighted members of the purine pathway being essential for C. jejuni whilst also finding that a functional potassium uptake system is essential. Protein-protein interaction networks using these essential gene lists also highlighted proteins in the purine pathway being major 'hub' proteins which have a large number of interactors across the network. When adding in two more species (C. lari and C. hyointestinalis) the essential gene list reduces to 261. Within these 261 essential genes, there are many genes that have been found to be essential in other bacteria. These include htrB and PEB4, which have previously been found as core virulence genes across Campylobacter species in other studies. There were 21 genes which have no known function with eight of these being associated with the membrane. These surface-associated essential genes may provide attractive targets. The essential gene lists presented will help to prioritise targets for the development of novel therapeutic and preventative interventions.
Topics: Humans; Campylobacter jejuni; Campylobacter coli; Campylobacter; Campylobacter Infections
PubMed: 37024800
DOI: 10.1186/s12866-023-02835-8 -
BMC Genomics Apr 2020Campylobacter jejuni and Campylobacter coli are major global causes of bacterial gastroenteritis. Whilst several individual colonisation and virulence factors have been...
BACKGROUND
Campylobacter jejuni and Campylobacter coli are major global causes of bacterial gastroenteritis. Whilst several individual colonisation and virulence factors have been identified, our understanding of their role in the transmission, pathogenesis and ecology of Campylobacter has been hampered by the genotypic and phenotypic diversity within C. jejuni and C. coli. Autotransporter proteins are a family of outer membrane or secreted proteins in Gram-negative bacteria such as Campylobacter, which are associated with virulence functions. In this study we have examined the distribution and predicted functionality of the previously described capC and the newly identified, related capD autotransporter gene families in Campylobacter.
RESULTS
Two capC-like autotransporter families, designated capC and capD, were identified by homology searches of genomes of the genus Campylobacter. Each family contained four distinct orthologs of CapC and CapD. The distribution of these autotransporter genes was determined in 5829 C. jejuni and 1347 C. coli genomes. Autotransporter genes were found as intact, complete copies and inactive formats due to premature stop codons and frameshift mutations. Presence of inactive and intact autotransporter genes was associated with C. jejuni and C. coli multi-locus sequence types, but for capC, inactivation was independent from the length of homopolymeric tracts in the region upstream of the capC gene. Inactivation of capC or capD genes appears to represent lineage-specific gene decay of autotransporter genes. Intact capC genes were predominantly associated with the C. jejuni ST-45 and C. coli ST-828 generalist lineages. The capD3 gene was only found in the environmental C. coli Clade 3 lineage. These combined data support a scenario of inter-lineage and interspecies exchange of capC and subsets of capD autotransporters.
CONCLUSIONS
In this study we have identified two novel, related autotransporter gene families in the genus Campylobacter, which are not uniformly present and exhibit lineage-specific associations and gene decay. The distribution and decay of the capC and capD genes exemplifies the erosion of species barriers between certain lineages of C. jejuni and C. coli, probably arising through co-habitation. This may have implications for the phenotypic variability of these two pathogens and provide opportunity for new, hybrid genotypes to emerge.
Topics: Campylobacter coli; Campylobacter jejuni; Gene Deletion; Genome, Bacterial; Phylogeny; Type V Secretion Systems; Virulence Factors
PubMed: 32306949
DOI: 10.1186/s12864-020-6704-z -
Microbial Genomics Oct 2021The intriguing recent discovery of strains, especially of clade 1, that (i) possess mosaic / alleles, (ii) demonstrate mixed multilocus sequence types (MLSTs) and (iii)...
The intriguing recent discovery of strains, especially of clade 1, that (i) possess mosaic / alleles, (ii) demonstrate mixed multilocus sequence types (MLSTs) and (iii) have undergone genome-wide introgression has led to the speculation that these two species may be involved in an accelerated rate of horizontal gene transfer that is progressively leading to the merging of both species in a process coined 'despeciation'. In an MLST-based neighbour-joining tree of a number of and isolates of different clades, three prominent isolates formed a seemingly separate cluster besides the previously described and clades. In the light of the suspected, ongoing genetic introgression between the and species, this cluster of isolates is proposed to present one of the hybrid clonal complexes in the despeciation process of the genus. Specific DNA methylation as well as restriction modification systems are known to be involved in selective uptake of external DNA and their role in such genetic introgression remains to be further investigated. In this study, the phylogeny and DNA methylation of these putative / hybrid strains were explored, their genomic mosaic structure caused by introgression was demonstrated and basic phenotypic assays were used to characterize these isolates. The genomes of the three hybrid strains were sequenced using PacBio SMRT sequencing, followed by methylome analysis by Restriction-Modification Finder and genome analysis by Parsnp, Smash++ and blast. Additionally, the strains were phenotypically characterized with respect to growth behaviour, motility, eukaryotic cell invasion and adhesion, autoagglutination, biofilm formation, and water survival ability. Our analyses show that the three hybrid strains are clade 1 . strains, which have acquired between 8.1 and 9.1 % of their genome from . The genomic segments acquired are distributed over the entire genome and do not form a coherent cluster. Most of the genes originating from are involved in chemotaxis and motility, membrane transport, cell signalling, or the resistance to toxic compounds such as bile acids. Interspecies gene transfer from has contributed 8.1-9.1% to the genome of three isolates and initiated the despeciation between and . Based on their functional annotation, the genes originating from enable the adaptation of the three strains to an intra-intestinal habitat. The transfer of a fused type II restriction-modification system that recognizes the CAYNNNNNCTC/GAGNNNNNRTG motif seems to be the key for the recombination of the genetic material with genomes.
Topics: Bacterial Typing Techniques; Campylobacter Infections; Campylobacter coli; Campylobacter jejuni; Chromosomes, Bacterial; DNA, Bacterial; Epigenome; Gene Transfer, Horizontal; Genome, Bacterial; Genomics; Multilocus Sequence Typing; Phylogeny; Sequence Analysis, DNA
PubMed: 34661518
DOI: 10.1099/mgen.0.000679 -
Poultry Science Jan 2012Human campylobacteriosis, an infection caused by the bacterium Campylobacter, is a major issue in the United States food system, especially for poultry products.... (Review)
Review
Human campylobacteriosis, an infection caused by the bacterium Campylobacter, is a major issue in the United States food system, especially for poultry products. According to the Center for Disease Control, campylobacterosis is estimated to affect over 2.4 million people annually. Campylobacter jejuni and Campylobacter coli are 2 species responsible for the majority of campylobacterosis infections. Phenotypic and genotypic typing methods are often used to discriminate between bacteria at the species and subspecies level and are often used to identify pathogenic organisms, such as C. jejuni and C. coli. This review describes the design as well as advantages and disadvantages for 3 current phenotypic techniques (biotyping, serotyping, and multilocus enzyme electrophoresis) and 6 genotypic techniques (multilocus sequence typing, PCR, pulse-field gel electrophoresis, ribotyping, flagellin typing, and amplified fragment length polymorphisms) for typing pathogenic Campylobacter spp.
Topics: Animals; Bacterial Typing Techniques; Campylobacter Infections; Campylobacter coli; Campylobacter jejuni; Chickens; Phenotype; Poultry Diseases; Reproducibility of Results
PubMed: 22184452
DOI: 10.3382/ps.2011-01414 -
Current Opinion in Infectious Diseases Oct 2014Recent work has added to the understanding of the burden of Campylobacter jejuni, C. coli, and non-jejuni/coli Campylobacter strains in children living in the developing... (Review)
Review
PURPOSE OF REVIEW
Recent work has added to the understanding of the burden of Campylobacter jejuni, C. coli, and non-jejuni/coli Campylobacter strains in children living in the developing world.
RECENT FINDINGS
New diagnostic modalities and carefully designed field studies are demonstrating that the burden of Campylobacter diarrhea in children in the developing world has been greatly underestimated. Furthermore, there is emerging recognition of an association between Campylobacter infection and malnutrition. Important progress has been made toward a Campylobacter jejuni vaccine. Finally, evidence of antibiotic resistance continues to be an important issue that is accentuated by the realization that the burden of disease is greater than previously recognized.
SUMMARY
Additional research is needed to refine our understanding of the epidemiology of Campylobacter infections in developing countries, in particular to improve estimates of the burden of Campylobacter diarrhea in endemic settings, to determine the impact of recurrent Campylobacter infections on child development, and to describe the prevalence and clinical significance of non-jejuni/coli Campylobacter infections. Progressive antibiotic resistance of isolates argues for augmented and expanded control measures of antibiotics in livestock. Continued work in vaccine development is warranted as is the extension of data available on the serotypes related to burden in different areas of the world and the relationship of serotypes to disease severity.
Topics: Anti-Bacterial Agents; Campylobacter Infections; Campylobacter coli; Campylobacter jejuni; Child; Child Nutrition Disorders; Cost of Illness; Developing Countries; Diarrhea; Disease Outbreaks; Drug Resistance, Microbial; Gastroenteritis; Humans; Prevalence; Water Supply
PubMed: 25023741
DOI: 10.1097/QCO.0000000000000091 -
Applied and Environmental Microbiology Apr 2020In a structured survey of all major chicken-meat producers in Australia, we investigated the antimicrobial resistance (AMR) and genomic characteristics of ( = 108)...
In a structured survey of all major chicken-meat producers in Australia, we investigated the antimicrobial resistance (AMR) and genomic characteristics of ( = 108) and ( = 96) from cecal samples of chickens at slaughter ( = 200). The majority of the (63%) and (86.5%) samples were susceptible to all antimicrobials. Fluoroquinolone resistance was detected among both (14.8%) and (5.2%), although this only included three sequence types (STs) and one ST, respectively. Multidrug resistance among strains of (0.9%) and (4.1%) was rare, and fluoroquinolone resistance, when present, was never accompanied by resistance to any other agent. Comparative genome analysis demonstrated that Australian isolates were found dispersed on different branches/clusters within the international collection. The major fluoroquinolone-resistant STs of (ST7323, ST2083, and ST2343) and (ST860) present in Australian chickens were similar to those of international isolates and have been reported previously in humans and animals overseas. The detection of a subpopulation of isolates exclusively resistant to fluoroquinolone was unexpected since most critically important antimicrobials such as fluoroquinolones are excluded from use in Australian livestock. A number of factors, including the low level of resistance to other antimicrobials, the absence of fluoroquinolone use, the adoption of measures for preventing spread of contagion between flocks, and particularly the genomic identities of isolates, all point to humans, pest species, or wild birds as being the most plausible source of organisms. This study also demonstrates the need for vigilance in the form of surveillance for AMR based on robust sampling to manage AMR risks in the food chain. is one of the most common causes of gastroenteritis in humans, with infections frequently resulting from exposure to undercooked poultry products. Although human illness is typically self-limiting, a minority of cases do require antimicrobial therapy. Ensuring that originating from meat chickens does not acquire resistance to fluoroquinolones is therefore a valuable outcome for public health. Australia has never legalized the use of fluoroquinolones in commercial chickens and until now fluoroquinolone-resistant has not been detected in the Australian poultry. This structured survey of meat chickens derived from all major Australian producers describes the unexpected emergence of fluoroquinolone resistance in and Genetic characterization suggests that these isolates may have evolved outside the Australian poultry sector and were introduced into poultry by humans, pest species, or wild birds. The findings dramatically underline the critical role of biosecurity in the overall fight against antimicrobial resistance.
Topics: Animals; Anti-Bacterial Agents; Australia; Campylobacter Infections; Campylobacter coli; Campylobacter jejuni; Chickens; Drug Resistance, Bacterial; Fluoroquinolones; Microbial Sensitivity Tests; Poultry Diseases
PubMed: 32033955
DOI: 10.1128/AEM.02765-19