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1.
Curr Biol ; 34(17): R829-R831, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39255768

RESUMO

A spatial-genomic analysis reveals that bird species living closer to humans have higher diversity of the pathogen Campylobacter and its antimicrobial resistance genes. This suggests that urbanization could promote pathogen transmission among wild animals and, potentially, humans.


Assuntos
Saúde Única , Animais , Humanos , Campylobacter/genética , Campylobacter/fisiologia , Aves/microbiologia , Farmacorresistência Bacteriana/genética , Urbanização , Infecções por Campylobacter/microbiologia , Infecções por Campylobacter/veterinária , Infecções por Campylobacter/epidemiologia , Doenças das Aves/microbiologia , Doenças das Aves/transmissão , Doenças das Aves/epidemiologia , Antibacterianos/farmacologia
2.
PLoS One ; 19(9): e0307572, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39241091

RESUMO

Enumeration of Campylobacter from environmental waters can be difficult due to its low concentrations, which can still pose a significant health risk. Spectrophotometry is an approach commonly used for fast detection of water-borne pollutants in water samples, but it has not been used for pathogen detection, which is commonly done through a laborious and time-consuming culture or qPCR Most Probable Number enumeration methods (i.e., MPN-PCR approaches). In this study, we proposed a new method, MPN-Spectro-ML, that can provide rapid evidence of Campylobacter detection and, hence, water concentrations. After an initial incubation, the samples were analysed using a spectrophotometer, and the spectrum data were used to train three machine learning (ML) models (i.e., supported vector machine - SVM, logistic regression-LR, and random forest-RF). The trained models were used to predict the presence of Campylobacter in the enriched water samples and estimate the most probable number (MPN). Over 100 stormwater, river, and creek samples (including both fresh and brackish water) from rural and urban catchments were collected to test the accuracy of the MPN-Spectro-ML method under various scenarios and compared to a previously standardised MPN-PCR method. Differences in the spectrum were found between positive and negative control samples, with two distinctive absorbance peaks between 540-542nm and 575-576nm for positive samples. Further, the three ML models had similar performance irrespective of the scenario tested with average prediction accuracy (ACC) and false negative rates at 0.763 and 13.8%, respectively. However, the predicted MPN of Campylobacter from the new method varied from the traditional MPN-PCR method, with a maximum Nash-Sutcliffe coefficient of 0.44 for the urban catchment dataset. Nevertheless, the MPN values based on these two methods were still comparable, considering the confidence intervals and large uncertainties associated with MPN estimation. The study reveals the potential of this novel approach for providing interim evidence of the presence and levels of Campylobacter within environmental water bodies. This, in turn, decreases the time from risk detection to management for the benefit of public health.


Assuntos
Campylobacter , Aprendizado de Máquina , Campylobacter/isolamento & purificação , Campylobacter/genética , Microbiologia da Água , Espectrofotometria/métodos , Rios/microbiologia , Rios/química
3.
Microb Genom ; 10(8)2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39213166

RESUMO

Campylobacter is the leading bacterial cause of infectious intestinal disease, but the pathogen typically accounts for a very small proportion of the overall stool microbiome in each patient. Diagnosis is even more difficult due to the fastidious nature of Campylobacter in the laboratory setting. This has, in part, driven a change in recent years, from culture-based to rapid PCR-based diagnostic assays which have improved diagnostic detection, whilst creating a knowledge gap in our clinical and epidemiological understanding of Campylobacter genotypes - no isolates to sequence. In this study, direct metagenomic sequencing approaches were used to assess the possibility of replacing genome sequences with metagenome sequences; metagenomic sequencing outputs were used to describe clinically relevant attributes of Campylobacter genotypes. A total of 37 diarrhoeal stool samples with Campylobacter and five samples with an unknown pathogen result were collected and processed with and without filtration, DNA was extracted, and metagenomes were sequenced by short-read sequencing. Culture-based methods were used to validate Campylobacter metagenome-derived genome (MDG) results. Sequence output metrics were assessed for Campylobacter genome quality and accuracy of characterization. Of the 42 samples passing quality checks for analysis, identification of Campylobacter to the genus and species level was dependent on Campylobacter genome read count, coverage and genome completeness. A total of 65% (24/37) of samples were reliably identified to the genus level through Campylobacter MDG, 73% (27/37) by culture and 97% (36/37) by qPCR. The Campylobacter genomes with a genome completeness of over 60% (n=21) were all accurately identified at the species level (100%). Of those, 72% (15/21) were identified to sequence types (STs), and 95% (20/21) accurately identified antimicrobial resistance (AMR) gene determinants. Filtration of stool samples enhanced Campylobacter MDG recovery and genome quality metrics compared to the corresponding unfiltered samples, which improved the identification of STs and AMR profiles. The phylogenetic analysis in this study demonstrated the clustering of the metagenome-derived with culture-derived genomes and revealed the reliability of genomes from direct stool sequencing. Furthermore, Campylobacter genome spiking percentages ranging from 0 to 2% total metagenome abundance in the ONT MinION sequencer, configured to adaptive sequencing, exhibited better assembly quality and accurate identification of STs, particularly in the analysis of metagenomes containing 2 and 1% of Campylobacter jejuni genomes. Direct sequencing of Campylobacter from stool samples provides clinically relevant and epidemiologically important genomic information without the reliance on cultured genomes.


Assuntos
Infecções por Campylobacter , Campylobacter , Fezes , Sequenciamento Completo do Genoma , Fezes/microbiologia , Humanos , Campylobacter/genética , Campylobacter/isolamento & purificação , Campylobacter/classificação , Sequenciamento Completo do Genoma/métodos , Infecções por Campylobacter/microbiologia , Genoma Bacteriano , Metagenoma , Metagenômica/métodos , Diarreia/microbiologia , Filogenia
4.
Biochemistry ; 63(18): 2369-2379, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39192839

RESUMO

Species within the Campylobacter genus are recognized as emerging human pathogens. Common to all known members of the genus is the presence of an asparagine-linked glycosylation pathway encoded by the pgl operon. Campylobacter species are divided into two major groups, Group I and Group II. To date, most biochemical studies have focused on the Group I species including Campylobacter jejuni. We recently reported that the Group II Campylobacter concisus pathway deviates from that of Group I by the inclusion of a C-6″-oxidized GalNAc (GalNAcA) at the third position installed by PglJ. Herein, we investigate the diversification of the PglH enzymes that act subsequent to installation of GalNAcA. The majority of pgl operons from Group II species, including C. concisus, encode two GT-B fold glycosyltransferases (GTs), PglH1 and PglH2. As the functions of these GTs were not clear by simple comparison of their sequences to that of C. jejuni PglH, further analyses were required. We show that subsequent to the action of PglJ, PglH2 installs the next HexNAc followed by PglH1 adding a single sugar. These steps diverge from the C. jejuni pathway not only in the identity of the sugar donors (UDP-GlcNAc) but also in installing single sugars rather than acting processively. These biochemical studies were extended via bioinformatics to identify sequence signatures that provide predictive capabilities for unraveling the prokaryotic glycan landscape. Phylogenetic analysis showed early divergence between the C. jejuni PglH orthologs and C. concisus PglH1/PglH2 orthologs, leading to diversification of the final glycan.


Assuntos
Campylobacter , Glicosiltransferases , Polissacarídeos , Glicosiltransferases/metabolismo , Glicosiltransferases/genética , Glicosiltransferases/química , Campylobacter/enzimologia , Campylobacter/genética , Campylobacter/metabolismo , Polissacarídeos/metabolismo , Glicosilação , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Campylobacter jejuni/enzimologia , Campylobacter jejuni/genética , Campylobacter jejuni/metabolismo , Óperon , Filogenia
5.
BMC Infect Dis ; 24(1): 808, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39123104

RESUMO

BACKGROUND: Campylobacter spp. is a significant etiological agent of bacterial gastroenteritis globally. In Burkina Faso (BFA), the actual impact of this pathogen on gastroenteritis is considerably underestimated, primarily due to inadequate surveillance systems. OBJECTIVES: This study aimed to investigate the proportion of Campylobacter species responsible for acute gastroenteritis among patients of all ages in urban and rural areas of BFA, using molecular biology techniques. STUDY DESIGN & METHODS: Between 2018 and 2021, faecal specimens were obtained from 1,295 individuals presenting with acute gastroenteritis. These samples underwent screening for the Campylobacter coli/jejuni/lari complex utilizing real-time polymerase chain reaction (PCR) assays. Subsequently, positive samples were subjected to species-level differentiation through the application of species-specific primers. RESULTS: Campylobacter spp. was detected in 25.0% (324/1,295) of the samples analysed. The majority of positive samples (95%, 308/324) were obtained from children under 5 years of age. Species identification was performed on a subset of 114 isolates, revealing 51 Campylobacter jejuni, 10 Campylobacter coli, and 53 Campylobacter isolates that remained unspeciated. CONCLUSIONS: This study reveals a significant prevalence of Campylobacter species among patients with acute gastroenteritis, with a particularly high incidence observed in children under 5 years of age. Based on these findings, the implementation of routine Campylobacter surveillance in public health laboratories is strongly recommended to better monitor and address this health concern.


Assuntos
Infecções por Campylobacter , Campylobacter , Fezes , Humanos , Burkina Faso/epidemiologia , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Pré-Escolar , Lactente , Campylobacter/isolamento & purificação , Campylobacter/genética , Campylobacter/classificação , Feminino , Masculino , Criança , Adulto , Adolescente , Fezes/microbiologia , Adulto Jovem , Pessoa de Meia-Idade , Gastroenterite/microbiologia , Gastroenterite/epidemiologia , Prevalência , Recém-Nascido , Campylobacter jejuni/isolamento & purificação , Campylobacter jejuni/genética , Campylobacter jejuni/classificação , Idoso , Enterite/microbiologia , Enterite/epidemiologia , Doença Aguda , Incidência
6.
Epidemiol Infect ; 152: e101, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39168635

RESUMO

Campylobacter spp. are leading bacterial gastroenteritis pathogens. Infections are largely underreported, and the burden of outbreaks may be underestimated. Current strategies of testing as few as one isolate per sample can affect attribution of cases to epidemiologically important sources with high Campylobacter diversity, such as chicken meat. Multiple culture method combinations were utilized to recover and sequence Campylobacter from 45 retail chicken samples purchased across Norwich, UK, selecting up to 48 isolates per sample. Simulations based on resampling were used to assess the impact of Campylobacter sequence type (ST) diversity on outbreak detection. Campylobacter was recovered from 39 samples (87%), although only one sample was positive through all broth, temperature, and plate combinations. Three species were identified (Campylobacter jejuni, Campylobacter coli, and Campylobacter lari), and 33% of samples contained two species. Positive samples contained 1-8 STs. Simulation revealed that up to 87 isolates per sample would be required to detect 95% of the observed ST diversity, and 26 isolates would be required for the average probability of detecting a random theoretical outbreak ST to reach 95%. An optimized culture approach and selecting multiple isolates per sample are essential for more complete Campylobacter recovery to support outbreak investigation and source attribution.


Assuntos
Campylobacter , Galinhas , Galinhas/microbiologia , Animais , Campylobacter/isolamento & purificação , Campylobacter/genética , Campylobacter/classificação , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Infecções por Campylobacter/veterinária , Campylobacter jejuni/isolamento & purificação , Campylobacter jejuni/genética , Campylobacter coli/isolamento & purificação , Campylobacter coli/genética , Microbiologia de Alimentos , Surtos de Doenças , Reino Unido/epidemiologia , Carne/microbiologia , Variação Genética , Campylobacter lari/genética , Campylobacter lari/isolamento & purificação
7.
Microb Pathog ; 194: 106810, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39029598

RESUMO

The study aimed to isolate and identify Aliarcobacter spp. and Campylobacter spp. from the uterine contents of cows and to determine the susceptibilities of the isolates to various antibiotics. For this purpose, a total of 63 cows (with repeat breeder, metritis, and healthy) uterine contents were collected from a slaughterhouse. Pre-enrichment and membrane filtration methods were used to isolate Aliarcobacter and Campylobacter spp., and phenotypic and molecular methods were used to identify the isolates. Antibacterial susceptibilities of the isolates were determined by the disc diffusion method. A total of 11 (17.46 %, 11/63) samples were found positive for both genera, and 12 isolates were obtained from these samples. Out of 9 Campylobacter isolates, 5, 3, and 1 were identified as C. jejuni, C. sputorum, and C. hyointestinalis, respectively. Also, two and one of Aliarcobacter spp. isolates were identified as Aliarcobacter sp. and A. butzleri, respectively. All isolates of both genera were found to be sensitive to amoxicillin-clavulanic acid, ampicillin, erythromycin, and enrofloxacin and resistant to trimethoprim + sulfamethoxazole. This is the first study that reported on the isolation of C. hyointestinalis from cattle uterine contents. It was concluded that Campylobacter and Aliarcobacter species should be considered among the most important etiological agents in uterine infections that cause infertility in cows. The isolation of Aliarcobacter and Campylobacter spp. from healthy cow uteri within the scope of this study suggests the possibility that these agents could colonize the uterus, similar to the colonization observed in the intestine and gallbladder.


Assuntos
Antibacterianos , Infecções por Campylobacter , Campylobacter , Doenças dos Bovinos , Testes de Sensibilidade Microbiana , Filogenia , Útero , Bovinos , Animais , Feminino , Antibacterianos/farmacologia , Campylobacter/efeitos dos fármacos , Campylobacter/isolamento & purificação , Campylobacter/genética , Campylobacter/classificação , Útero/microbiologia , Doenças dos Bovinos/microbiologia , Infecções por Campylobacter/microbiologia , Infecções por Campylobacter/veterinária , RNA Ribossômico 16S/genética , Farmacorresistência Bacteriana , Matadouros , DNA Bacteriano/genética
8.
mBio ; 15(9): e0110124, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39072641

RESUMO

Various species of campylobacters cause significant disease problems in both humans and animals. The continuing development of tools and methods for genetic and molecular manipulation of campylobacters enables the detailed study of bacterial virulence and disease pathogenesis. Campylobacter hepaticus is an emerging pathogen that causes spotty liver disease (SLD) in poultry. SLD has a significant economic and animal welfare impact as the disease results in elevated mortalities and significant decreases in egg production. Although potential virulence genes of C. hepaticus have been identified, they have not been further studied and characterized, as appropriate genetic tools and methods to transform and perform mutagenesis studies in C. hepaticus have not been available. In this study, the genetic manipulation of C. hepaticus is reported, with the development of novel plasmid vectors, methods for transformation, site-specific mutagenesis, and mutant complementation. These tools were used to delete the pglB gene, an oligosaccharyltransferase, a central enzyme of the N-glycosylation pathway, by allelic exchange. In the mutant strain, N-glycosylation was completely abolished. The tools and methods developed in this study represent innovative approaches that can be applied to further explore important virulence factors of C. hepaticus and other closely related Campylobacter species. IMPORTANCE: Spotty liver disease (SLD) of layer chickens, caused by infection with Campylobacter hepaticus, is a significant economic and animal welfare burden on an important food production industry. Currently, SLD is controlled using antibiotics; however, alternative intervention methods are needed due to increased concerns associated with environmental contamination with antibiotics, and the development of antimicrobial resistance in many bacterial pathogens of humans and animals. This study has developed methods that have enabled the genetic manipulation of C. hepaticus. To validate the methods, the pglB gene was inactivated by allelic exchange to produce a C. hepaticus strain that could no longer N-glycosylate proteins. Subsequently, the mutation was complemented by reintroduction of the gene in trans, on a plasmid vector, to demonstrate that the phenotypic changes noted were caused by the mutation of the targeted gene. The tools developed enable ongoing studies to understand other virulence mechanisms of this important emerging pathogen.


Assuntos
Infecções por Campylobacter , Campylobacter , Doenças das Aves Domésticas , Animais , Campylobacter/genética , Campylobacter/patogenicidade , Campylobacter/metabolismo , Glicosilação , Doenças das Aves Domésticas/microbiologia , Infecções por Campylobacter/microbiologia , Infecções por Campylobacter/veterinária , Virulência/genética , Galinhas , Aves Domésticas/microbiologia , Plasmídeos/genética , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Mutagênese Sítio-Dirigida , Hexosiltransferases/genética , Hexosiltransferases/metabolismo , Vetores Genéticos
9.
Braz J Microbiol ; 55(3): 2547-2556, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38977544

RESUMO

Campylobacter is gram-negative bacteria considered the predominant genera isolated from poultry samples and associated with gastroenteritis. Due to the problems in conventional cultural methods of time-consuming and technically demanding requirements, a rapid and feasible method for their identification and discrimination of the closely related spp. Including Campylobacter coli, Campylobacter fetus, and Campylobacter jejuni is needed. This study analyzes the chicken and sheep meats samples (n = 125) using culture and pre-enrichment-based Quadraplex real-time PCR by targeting OrfA, CstA, HipO, and 16 S rRNA genes of C. coli, C. fetus, C. jejuni and Campylobacter spp. Respectively. The analysis of 125 chicken and sheep meat samples by culture and real-time PCR showed high concordance between the results of the two methods. The present study show high prevalence of Campylobacter species (35% and 32% from chicken and meat respectively) of which C. jejuni were the most abundant. Reaction efficiencies were between 90 and 110%, and detect as low as 8.9 fg in C. jejuni. The need for quick detection and discrimination methods in sheep and chicken meat can be met using the described Quadraplex real-time PCR methodology.


Assuntos
Campylobacter coli , Campylobacter jejuni , Galinhas , Carne , Reação em Cadeia da Polimerase em Tempo Real , Animais , Galinhas/microbiologia , Ovinos/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Campylobacter coli/genética , Campylobacter coli/isolamento & purificação , Campylobacter coli/classificação , Campylobacter jejuni/genética , Campylobacter jejuni/isolamento & purificação , Campylobacter jejuni/classificação , Carne/microbiologia , Campylobacter fetus/genética , Campylobacter fetus/isolamento & purificação , Campylobacter fetus/classificação , Campylobacter/genética , Campylobacter/isolamento & purificação , Campylobacter/classificação , Microbiologia de Alimentos , DNA Bacteriano/genética
10.
Microb Biotechnol ; 17(6): e14480, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38858807

RESUMO

The application of bacterial oligosaccharyltransferases (OSTs) such as the Campylobacter jejuni PglB for glycoengineering has attracted considerable interest in glycoengineering and glycoconjugate vaccine development. However, PglB has limited specificity for glycans that can be transferred to candidate proteins, which along with other factors is dependent on the reducing end sugar of glycans. In this study, we developed a cell-free glycosylation assay that offers the speed and simplicity of a 'yes' or 'no' determination. Using the assay, we tested the activity of eleven PglBs from Campylobacter species and more distantly related bacteria. The following assorted glycans with diverse reducing end sugars were tested for transfer, including Streptococcus pneumoniae capsule serotype 4, Salmonella enterica serovar Typhimurium O antigen (B1), Francisella tularensis O antigen, Escherichia coli O9 antigen and Campylobacter jejuni heptasaccharide. Interestingly, while PglBs from the same genus showed high activity, whereas divergent PglBs differed in their transfer of glycans to an acceptor protein. Notably for glycoengineering purposes, Campylobacter hepaticus and Campylobacter subantarcticus PglBs showed high glycosylation efficiency, with C. hepaticus PglB potentially being useful for glycoconjugate vaccine production. This study demonstrates the versatility of the cell-free assay in rapidly assessing an OST to couple glycan/carrier protein combinations and lays the foundation for future screening of PglBs by linking amino acid similarity to glycosyltransferase activity.


Assuntos
Hexosiltransferases , Proteínas de Membrana , Hexosiltransferases/genética , Hexosiltransferases/metabolismo , Hexosiltransferases/química , Glicosilação , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Campylobacter/genética , Campylobacter/enzimologia , Campylobacter/metabolismo , Polissacarídeos/metabolismo , Sistema Livre de Células , Campylobacter jejuni/enzimologia , Campylobacter jejuni/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Glicoconjugados/metabolismo
11.
Front Cell Infect Microbiol ; 14: 1356907, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38863832

RESUMO

Introduction: Microbial community composition is closely associated with host disease onset and progression, underscoring the importance of understanding host-microbiota dynamics in various health contexts. Methods: In this study, we utilized full-length 16S rRNA gene sequencing to conduct species-level identification of the microorganisms in the oral cavity of a giant panda (Ailuropoda melanoleuca) with oral malignant fibroma. Results: We observed a significant difference between the microbial community of the tumor side and non-tumor side of the oral cavity of the giant panda, with the latter exhibiting higher microbial diversity. The tumor side was dominated by specific microorganisms, such as Fusobacterium simiae, Porphyromonas sp. feline oral taxon 110, Campylobacter sp. feline oral taxon 100, and Neisseria sp. feline oral taxon 078, that have been reported to be associated with tumorigenic processes and periodontal diseases in other organisms. According to the linear discriminant analysis effect size analysis, more than 9 distinct biomarkers were obtained between the tumor side and non-tumor side samples. Furthermore, the Kyoto Encyclopedia of Genes and Genomes analysis revealed that the oral microbiota of the giant panda was significantly associated with genetic information processing and metabolism, particularly cofactor and vitamin, amino acid, and carbohydrate metabolism. Furthermore, a significant bacterial invasion of epithelial cells was predicted in the tumor side. Discussion: This study provides crucial insights into the association between oral microbiota and oral tumors in giant pandas and offers potential biomarkers that may guide future health assessments and preventive strategies for captive and aging giant pandas.


Assuntos
Campylobacter , Fusobacterium , Microbiota , Boca , Porphyromonas , RNA Ribossômico 16S , Ursidae , Ursidae/microbiologia , Animais , RNA Ribossômico 16S/genética , Porphyromonas/genética , Porphyromonas/isolamento & purificação , Porphyromonas/classificação , Campylobacter/genética , Campylobacter/isolamento & purificação , Campylobacter/classificação , Boca/microbiologia , Fusobacterium/genética , Fusobacterium/isolamento & purificação , Fibroma/microbiologia , Fibroma/veterinária , Neisseria/isolamento & purificação , Neisseria/genética , Neisseria/classificação , Neoplasias Bucais/microbiologia , Neoplasias Bucais/veterinária , Neoplasias Bucais/patologia , Filogenia , Análise de Sequência de DNA
12.
Artigo em Inglês | MEDLINE | ID: mdl-38842428

RESUMO

In a previous study characterizing Campylobacter strains deficient in selenium metabolism, 50 strains were found to be similar to, but distinct from, the selenonegative species Campylobacter lanienae. Initial characterization based on multilocus sequence typing and the phylogeny of a set of 20 core genes determined that these strains form three putative taxa within the selenonegative cluster. A polyphasic study was undertaken here to further clarify their taxonomic position within the genus. The 50 selenonegative strains underwent phylogenetic analyses based on the sequences of the 16S rRNA gene and an expanded set of 330 core genes. Standard phenotypic testing was also performed. All strains were microaerobic and anaerobic, Gram-negative, spiral or curved cells with some displaying coccoid morphologies. Strains were motile, oxidase, catalase, and alkaline phosphatase positive, urease negative, and reduced nitrate. Strains within each clade had unique phenotypic profiles that distinguished them from other members of the genus. Core genome phylogeny clearly placed the 50 strains into three clades. Pairwise average nucleotide identity and digital DNA-DNA hybridization values were all below the recommended cut-offs for species delineation with respect to C. lanienae and other related Campylobacter species. The data presented here clearly show that these strains represent three novel species within the genus, for which the names Campylobacter devanensis sp. nov. (type strain RM3662T=LMG 33097T=NCTC 15074T), Campylobacter porcelli sp. nov. (type strain RM6137T=LMG 33098T=CCUG 77054T=NCTC 15075T) and Campylobacter vicugnae sp. nov. (type strain RM12175T=LMG 33099T=CCUG 77055T=NCTC 15076T) are proposed.


Assuntos
Técnicas de Tipagem Bacteriana , Campylobacter , DNA Bacteriano , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA , RNA Ribossômico 16S/genética , Campylobacter/genética , Campylobacter/classificação , Campylobacter/isolamento & purificação , Animais , DNA Bacteriano/genética , Suínos , Ruminantes/microbiologia
13.
Res Microbiol ; 175(7): 104219, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38945250

RESUMO

Despite being classified as microaerophilic microorganisms, most Campylobacter species can grow anaerobically, using formate or molecular hydrogen (H2) as electron donors, and various nitrogenous and sulfurous compounds as electron acceptors. Herein, we showed that both l-asparagine (l-Asn) and l-aspartic acid (l-Asp) bolster H2-driven anaerobic growth in several Campylobacter species, whereas the d-enantiomer form of both asparagine (d-Asn) and aspartic acid (d-Asp) only increased anaerobic growth in Campylobacter concisus strain 13826 and Campylobacter ureolyticus strain NCTC10941. A gene annotated as racD encoding for a putative d/l-Asp racemase was identified in the genome of both strains. Disruption of racD in Cc13826 resulted in the inability of the mutant strain to use either d-enantiomer during anaerobic growth. Hence, our results suggest that the racD gene is required for campylobacters to use either d-Asp or d-Asn. The use of d-Asp by various human opportunistic bacterial pathogens, including C. concisus, C. ureolyticus, and also possibly select strains of Campylobacter gracilis, Campylobacter rectus and Campylobacter showae, is significant, because d-Asp is an important signal molecule for both human nervous and neuroendocrine systems. To our knowledge, this is the first report of pathogens scavenging a d-amino acid essential for human health.


Assuntos
Campylobacter , Campylobacter/genética , Campylobacter/metabolismo , Campylobacter/crescimento & desenvolvimento , Anaerobiose , Humanos , Isomerases de Aminoácido/metabolismo , Isomerases de Aminoácido/genética , Hidrogênio/metabolismo , Ácido D-Aspártico/metabolismo , Asparagina/metabolismo
14.
Microb Genom ; 10(5)2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38739120

RESUMO

Cutaneous ulcers are common in yaws-endemic areas. Although often attributed to 'Treponema pallidum subsp. pertenue' and Haemophilus ducreyi, quantitative PCR has highlighted a significant proportion of these ulcers are negative for both pathogens and are considered idiopathic. This is a retrospective analysis utilising existing 16S rRNA sequencing data from two independent yaws studies that took place in Ghana and the Solomon Islands. We characterized bacterial diversity in 38 samples to identify potential causative agents for idiopathic cutaneous ulcers. We identified a diverse bacterial profile, including Arcanobacterium haemolyticum, Campylobacter concisus, Corynebacterium diphtheriae, Staphylococcus spp. and Streptococcus pyogenes, consistent with findings from previous cutaneous ulcer microbiome studies. No single bacterial species was universally present across all samples. The most prevalent bacterium, Campylobacter ureolyticus, appeared in 42% of samples, suggesting a multifactorial aetiology for cutaneous ulcers in yaws-endemic areas. This study emphasizes the need for a nuanced understanding of potential causative agents. The findings prompt further exploration into the intricate microbial interactions contributing to idiopathic yaw-like ulcers, guiding future research toward comprehensive diagnostic and therapeutic strategies.


Assuntos
Microbiota , RNA Ribossômico 16S , Úlcera Cutânea , Humanos , RNA Ribossômico 16S/genética , Úlcera Cutânea/microbiologia , Gana , Masculino , Bouba/microbiologia , Bouba/diagnóstico , Estudos Retrospectivos , Feminino , Adulto , Bactérias/genética , Bactérias/classificação , Bactérias/isolamento & purificação , Melanesia , Pessoa de Meia-Idade , Staphylococcus/genética , Staphylococcus/isolamento & purificação , Staphylococcus/classificação , Streptococcus pyogenes/genética , Streptococcus pyogenes/isolamento & purificação , Streptococcus pyogenes/classificação , Arcanobacterium/genética , Arcanobacterium/isolamento & purificação , Campylobacter/genética , Campylobacter/isolamento & purificação , Campylobacter/classificação
15.
J Food Prot ; 87(7): 100308, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38815809

RESUMO

Human gastrointestinal infections caused by Campylobacter species is the second most important foodborne illness after salmonellosis worldwide. Poultry represent one of the main sources of Campylobacter organisms. In the present study, the short variable region of flagellin gene (SVR-flaA) typing was carried out to determine the variation among the circulating strains of Campylobacter jejuni and Campylobacter coli. The C. jejuni and C. coli isolated from poultry and poultry meat were screened for the presence of virulence determinants like cadF, flaA, cdtB, and wlaN gene. The screening for wlaN gene is crucial in view of the fact that most patients with Guillian Barre's (GB) syndrome with a preceding history of diarrheal illness have been found to harbor wlaN gene-positive C jejuni strains. Out of the 200 samples comprising poultry meat and cloacal swabs, 21.5% of samples were found to harbor Campylobacter spp. of which 2.5% were Campylobacter jejuni, and 19% were confirmed as Campylobacter coli. The cadF, flaA, cdtB virulence genes were detected in all the Campylobacter spp. isolated in the present study. The presence of the wlaN gene in the Campylobacter jejuni isolated in the present study may pose a public health threat with long-term human health implications. The SVR-flaA typing of twelve Campylobacter isolates obtained in the present study revealed that Campylobacter coli flaA sequence OL471375 is a new strain with a novel allele type 1,675 and peptide sequence 5 which stands deposited in pubMLST database for Campylobacter. The other flaA-SVR gene sequences identified in this study were OL471369, OL471370, OL471371, OL471372, OL471373, and OL471374. Among twelve Campylobacter spp., three distinct DdeI-RFLP patterns were observed, each varying in size from 100 to 1,000 base pairs. Antimicrobial profiling of the Campylobacter spp. isolated in the present study revealed that 50% of the strains were multidrug resistant. All the Campylobacter spp. were resistant to ciprofloxacin (CIP), ampicillin (AMP), penicillin (PEN), and nalidixic acid (NAL) whereas 57.1% of strains were resistant to tetracycline (TET) and erythromycin (ERY) 28% to amoxicillin (AMX) and enrofloxacin (ENO), 85% to amikacin (AMK). The high degree of resistance to fluoroquinolones observed in the present study is crucial in view of fluoroquinolones being drugs of choice for the treatment of human Campylobacter infections.


Assuntos
Campylobacter coli , Campylobacter jejuni , Farmacorresistência Bacteriana Múltipla , Flagelina , Aves Domésticas , Animais , Flagelina/genética , Humanos , Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/genética , Índia , Campylobacter coli/efeitos dos fármacos , Campylobacter coli/genética , Virulência , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Fatores de Virulência/genética , Campylobacter/efeitos dos fármacos , Campylobacter/genética , Carne/microbiologia , Variação Genética , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana
16.
BMC Microbiol ; 24(1): 155, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704526

RESUMO

BACKGROUND: The in-depth understanding of the role of lateral genetic transfer (LGT) in phage-prophage interactions is essential to rationalizing phage applications for human and animal therapy, as well as for food and environmental safety. This in silico study aimed to detect LGT between phages of potential industrial importance and their hosts. METHODS: A large array of genetic recombination detection algorithms, implemented in SplitsTree and RDP4, was applied to detect LGT between various Escherichia, Listeria, Salmonella, Campylobacter, Staphylococcus, Pseudomonas, and Vibrio phages and their hosts. PHASTER and RAST were employed respectively to identify prophages across the host genome and to annotate LGT-affected genes with unknown functions. PhageAI was used to gain deeper insights into the life cycle history of recombined phages. RESULTS: The split decomposition inferences (bootstrap values: 91.3-100; fit: 91.433-100), coupled with the Phi (0.0-2.836E-12) and RDP4 (P being well below 0.05) statistics, provided strong evidence for LGT between certain Escherichia, Listeria, Salmonella, and Campylobacter virulent phages and prophages of their hosts. The LGT events entailed mainly the phage genes encoding for hypothetical proteins, while some of these genetic loci appeared to have been affected even by intergeneric recombination in specific E. coli and S. enterica virulent phages when interacting with their host prophages. Moreover, it is shown that certain L. monocytogenes virulent phages could serve at least as the donors of the gene loci, involved in encoding for the basal promoter specificity factor, for L. monocytogenes. In contrast, the large genetic clusters were determined to have been simultaneously exchanged by many S. aureus prophages and some Staphylococcus temperate phages proposed earlier as potential therapeutic candidates (in their native or modified state). The above genetic clusters were found to encompass multiple genes encoding for various proteins, such as e.g., phage tail proteins, the capsid and scaffold proteins, holins, and transcriptional terminator proteins. CONCLUSIONS: It is suggested that phage-prophage interactions, mediated by LGT (including intergeneric recombination), can have a far-reaching impact on the co-evolutionary trajectories of industrial phages and their hosts especially when excessively present across microbially rich environments.


Assuntos
Prófagos , Recombinação Genética , Prófagos/genética , Campylobacter/virologia , Campylobacter/genética , Staphylococcus/virologia , Staphylococcus/genética , Transferência Genética Horizontal , Bacteriófagos/genética , Bacteriófagos/fisiologia , Bacteriófagos/classificação , Listeria/virologia , Listeria/genética , Salmonella/virologia , Salmonella/genética , Evolução Molecular , Bactérias/virologia , Bactérias/genética
17.
BMC Infect Dis ; 24(1): 512, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38778271

RESUMO

AIM: Diarrhea is a common disease in immunocompromised patients and can be associated with greater morbidity and even mortality. Therefore, the present study was designed to determine the prevalence of Aeromonas spp., Campylobacter spp., and C. difficile among immunocompromised children. METHODS: This study was conducted on 130 stool samples from patients with diarrhea who had defects in the immune system and were referred to Hazrat Masoumeh Children's Hospital in Qom. Demographic information, clinical symptoms, immune status, and duration of chemotherapy were also recorded for each child. DNAs were extracted from the stool, and then direct PCR assays were done by specific primers for the detection of Aeromonas spp., Campylobacter spp., and toxigenic C. difficile, including tcdA/B and cdtA/B genes. Co-infection in patients was also evaluated. RESULTS: 60.8% and 39.2% were male and female, respectively, with a m ± SD age of 56.72 ± 40.49 months. Most cases of immunocompromised states were related to Acute Lymphocytic Leukemia (77.7%) and Non-Hodgkin Lymphoma (14.6%). 93.1% of patients were undergoing chemotherapy during the study. Among patients, most clinical symptoms were related to bloody diarrhea (98.5%) and fever (92.3%). Based on PCR, 14.6, 9.2, and 1.5% were positive for Aeromonas spp., C. difficile, and C. jejuni, respectively. Among the C. difficile-positive cases, the tcdA gene was only detected in one patient. In total, three co-infections were identified, which included Aeromonas spp./C. difficile (tcdA+), C. jejuni/C. difficile, and C. jejuni/Aeromonas spp. CONCLUSIONS: This is the first study in Iran to investigate the simultaneous prevalence of some pathogens in immunocompromised children with diarrhea. Because Aeromonas spp., Campylobacter spp., and C. difficile are not routinely detected in some laboratories, infections caused by them are underappreciated in the clinic. Our results showed that these pathogens are present in our region and can cause gastroenteritis in children, especially those with underlying diseases. Therefore, increasing the level of hygiene in some areas and controlling bacterial diarrheal diseases should be given more attention by health officials.


Assuntos
Aeromonas , Campylobacter , Clostridioides difficile , Infecções por Clostridium , Diarreia , Fezes , Hospedeiro Imunocomprometido , Humanos , Feminino , Masculino , Pré-Escolar , Diarreia/microbiologia , Diarreia/epidemiologia , Criança , Aeromonas/isolamento & purificação , Aeromonas/genética , Prevalência , Clostridioides difficile/genética , Clostridioides difficile/isolamento & purificação , Campylobacter/isolamento & purificação , Campylobacter/genética , Lactente , Fezes/microbiologia , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/microbiologia , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Adolescente , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Coinfecção/microbiologia , Coinfecção/epidemiologia
18.
Vet Res Commun ; 48(4): 2621-2627, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38556573

RESUMO

Campylobacter spp. is recognized as one of the most common pathogens involved in the development of gastrointestinal infections in humans. The current study aimed to enhance the knowledge on the occurrence and molecular characterization of Campylobacter spp. in pigs and cattle origin caecum samples (n = 56) collected in one year, from nine Romanian slaughterhouses, and to determine the antimicrobial resistance profile of the isolated strains. All Campylobacter spp. strains (n = 41) isolated from swine and cattle caecum samples were analyzed in terms of antimicrobial resistance, in accordance with the EURL protocol and with the Commission Implementing Decision No. 2020/1729. The prevalence rate for C. coli. in pig caecum samples was 92.3% (36/39), and the prevalence of C. jejuni, in cattle origin samples was 29.4% (5/17). C. coli strains isolated from pigs proved resistant to tetracycline 75% (27/36), ciprofloxacin 69.4% (25/36), erythromycin 8.3% (3/36), ertapenem 2.8% (1/36) and gentamicin 2.8% (1/36), but no resistance was observed towards chloramphenicol. C. jejuni strains originating from cattle expressed resistance to ciprofloxacin 60.0% (3/5) and tetracycline 20.0% (1/5), but they were susceptible to chloramphenicol, erythromycin, ertapenem and gentamicin. In the present study, 19.5% (7/36) C. coli strains isolated from pigs were identified as multidrug-resistant (MDR) bacteria. The obtained results demonstrated that pigs especially, but cattle to, can be considered important natural reservoirs for zoonotic multidrug-resistant Campylobacter strains, having a stimulating effect for further studies aiming at the molecular screening of the genotypic antimicrobial resistance processing of a higher number of samples.


Assuntos
Antibacterianos , Campylobacter , Doenças dos Bovinos , Farmacorresistência Bacteriana , Doenças dos Suínos , Animais , Romênia/epidemiologia , Bovinos , Suínos , Antibacterianos/farmacologia , Campylobacter/efeitos dos fármacos , Campylobacter/isolamento & purificação , Campylobacter/genética , Campylobacter/classificação , Doenças dos Suínos/microbiologia , Doenças dos Suínos/epidemiologia , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/epidemiologia , Infecções por Campylobacter/veterinária , Infecções por Campylobacter/microbiologia , Infecções por Campylobacter/epidemiologia , Testes de Sensibilidade Microbiana , Matadouros , Ceco/microbiologia , Fenótipo , Prevalência
19.
J Vis Exp ; (204)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38465948

RESUMO

This article presents a rapid yet robust protocol for isolating Campylobacter spp. from raw meats, specifically focusing on Campylobacter jejuni and Campylobacter coli. The protocol builds upon established methods, ensuring compatibility with the prevailing techniques employed by regulatory bodies such as the Food and Drug Administration (FDA) and the U.S. Department of Agriculture (USDA) in the USA, as well as the International Organization for Standardization (ISO) in Europe. Central to this protocol is collecting a rinsate, which is concentrated and resuspended in Bolton Broth media containing horse blood. This medium has been proven to facilitate the recovery of stressed Campylobacter cells and reduce the required enrichment duration by 50%. The enriched samples are then transferred onto nitrocellulose membranes on brucella plates. To improve the sensitivity and specificity of the method, 0.45 µm and 0.65 µm pore-size filter membranes were evaluated. Data revealed a 29-fold increase in cell recovery with the 0.65 µm pore-size filter compared to the 0.45 µm pore-size without impacting specificity. The highly motile characteristics of Campylobacter allow cells to actively move through the membrane filters towards the agar medium, which enables effective isolation of pure Campylobacter colonies. The protocol incorporates multiplex quantitative real-time polymerase chain reaction (mqPCR) assay to identify the isolates at the species level. This molecular technique offers a reliable and efficient means of species identification. Investigations conducted over the past twelve years involving retail meats have demonstrated the ability of this method to enhance recovery of Campylobacter from naturally contaminated meat samples compared to current reference methods. Furthermore, this protocol boasts reduced preparation and processing time. As a result, it presents a promising alternative for the efficient recovery of Campylobacter from meat. Moreover, this procedure can be seamlessly integrated with DNA-based methods, facilitating rapid screening of positive samples alongside comprehensive whole-genome sequencing analysis.


Assuntos
Campylobacter jejuni , Campylobacter , Animais , Cavalos , Galinhas , Microbiologia de Alimentos , Carne , Campylobacter/genética , Meios de Cultura
20.
mSystems ; 9(4): e0121823, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38530055

RESUMO

Campylobacter species are typically helical shaped, Gram-negative, and non-spore-forming bacteria. Species in this genus include established foodborne and animal pathogens as well as emerging pathogens. The accumulation of genomic data from the Campylobacter genus has increased exponentially in recent years, accompanied by the discovery of putative new species. At present, the lack of a standardized species boundary complicates distinguishing established and novel species. We defined the Campylobacter genus core genome (500 loci) using publicly available Campylobacter complete genomes (n = 498) and constructed a core genome phylogeny using 2,193 publicly available Campylobacter genomes to examine inter-species diversity and species boundaries. Utilizing 8,440 Campylobacter genomes representing 33 species and 8 subspecies, we found species delineation based on an average nucleotide identity (ANI) cutoff of 94.2% is consistent with the core genome phylogeny. We identified 60 ANI genomic species that delineated Campylobacter species in concordance with previous comparative genetic studies. All pairwise ANI genomic species pairs had in silico DNA-DNA hybridization scores of less than 70%, supporting their delineation as separate species. We provide the tool Campylobacter Genomic Species typer (CampyGStyper) that assigns ANI genomic species to query genomes based on ANI similarities to medoid genomes from each ANI genomic species with an accuracy of 99.96%. The ANI genomic species definitions proposed here allow consistent species definition in the Campylobacter genus and will facilitate the detection of novel species in the future.IMPORTANCEIn recent years, Campylobacter has gained recognition as the leading cause of bacterial gastroenteritis worldwide, leading to a substantial rise in the collection of genomic data of the Campylobacter genus in public databases. Currently, a standardized Campylobacter species boundary at the genomic level is absent, leading to challenges in detecting emerging pathogens and defining putative novel species within this genus. We used a comprehensive representation of genomes of the Campylobacter genus to construct a core genome phylogenetic tree. Furthermore, we found an average nucleotide identity (ANI) of 94.2% as the optimal cutoff to define the Campylobacter species. Using this cutoff, we identified 60 ANI genomic species which provided a standardized species definition and nomenclature. Importantly, we have developed Campylobacter Genomic Species typer (CampyGStyper), which can robustly and accurately assign these ANI genomic species to Campylobacter genomes, thereby aiding pathogen surveillance and facilitating evolutionary and epidemiological studies of existing and emerging pathogens in the genus Campylobacter.


Assuntos
Campylobacter , Animais , Filogenia , Campylobacter/genética , Genoma Bacteriano/genética , Genes Bacterianos , DNA
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