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1.
Curr Top Microbiol Immunol ; 431: 59-78, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33620648

RESUMO

The zoonotic pathogen Campylobacter is the leading cause for bacterial foodborne infections in humans. Campylobacters are most commonly transmitted via the consumption of undercooked poultry meat or raw milk products. The decreasing costs of whole genome sequencing enabled large genome-based analyses of the evolution and population structure of this pathogen, as well as the development of novel high-throughput molecular typing methods. Here, we review the evolutionary development and the population diversity of the two most clinically relevant Campylobacter species; C. jejuni and C. coli. The state-of-the-art phylogenetic studies showed clustering of C. jejuni lineages into host specialists and generalists with coexisting lifestyles in chicken and livestock-associated hosts, as well as the separation of C. coli isolates of riparian origin (waterfowl, water) from C. coli isolated from clinical and farm-related samples. We will give an overview of recombination between both species and the potential impact of horizontal gene transfer on host adaptation in Campylobacter. Additionally, this review briefly places the current knowledge of the population structure of other Campylobacter species such as C. lari, C. concisus and C. upsaliensis into perspective. We also provide an overview of how molecular typing methods such as multilocus sequence typing (MLST) and whole genome MLST have been used to detect and trace Campylobacter outbreaks along the food chain.


Assuntos
Infecções por Campylobacter , Campylobacter jejuni , Campylobacter , Campylobacter/genética , Infecções por Campylobacter/epidemiologia , Campylobacter jejuni/genética , Genômica , Humanos , Tipagem de Sequências Multilocus , Filogenia
2.
Curr Top Microbiol Immunol ; 431: 265-292, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33620655

RESUMO

Thermophilic Campylobacter, in particular Campylobacter jejuni, C. coli and C. lari are the main relevant Campylobacter species for human infections. Due to their high capacity of genetic exchange by horizontal gene transfer (HGT), rapid adaptation to changing environmental and host conditions contribute to successful spreading and persistence of these foodborne pathogens. However, extensive HGT can exert dangerous side effects for the bacterium, such as the incorporation of gene fragments leading to disturbed gene functions. Here we discuss mechanisms of HGT, notably natural transformation, conjugation and bacteriophage transduction and limiting regulatory strategies of gene transfer. In particular, we summarize the current knowledge on how the DNA macromolecule is exchanged between single cells. Mechanisms to stimulate and to limit HGT obviously coevolved and maintained an optimal balance. Chromosomal rearrangements and incorporation of harmful mutations are risk factors for survival and can result in drastic loss of fitness. In Campylobacter, the restricted recognition and preferential uptake of free DNA from relatives are mediated by a short methylated DNA pattern and not by a classical DNA uptake sequence as found in other bacteria. A class two CRISPR-Cas system is present but also other DNases and restriction-modification systems appear to be important for Campylobacter genome integrity. Several lytic and integrated bacteriophages have been identified, which contribute to genome diversity. Furthermore, we focus on the impact of gene transfer on the spread of antibiotic resistance genes (resistome) and persistence factors. We discuss remaining open questions in the HGT field, supposed to be answered in the future by current technologies like whole-genome sequencing and single-cell approaches.


Assuntos
Bacteriófagos , Campylobacter jejuni , Campylobacter , Bacteriófagos/genética , Campylobacter/genética , Campylobacter jejuni/genética , Resistência Microbiana a Medicamentos , Transferência Genética Horizontal , Humanos
3.
PLoS One ; 15(12): e0244031, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33378351

RESUMO

Ecotin, first described in Escherichia coli, is a potent inhibitor of a broad range of serine proteases including those typically released by the innate immune system such as neutrophil elastase (NE). Here we describe the identification of ecotin orthologs in various Campylobacter species, including Campylobacter rectus and Campylobacter showae residing in the oral cavity and implicated in the development and progression of periodontal disease in humans. To investigate the function of these ecotins in vitro, the orthologs from C. rectus and C. showae were recombinantly expressed and purified from E. coli. Using CmeA degradation/protection assays, fluorescence resonance energy transfer and NE activity assays, we found that ecotins from C. rectus and C. showae inhibit NE, factor Xa and trypsin, but not the Campylobacter jejuni serine protease HtrA or its ortholog in E. coli, DegP. To further evaluate ecotin function in vivo, an E. coli ecotin-deficient mutant was complemented with the C. rectus and C. showae homologs. Using a neutrophil killing assay, we demonstrate that the low survival rate of the E. coli ecotin-deficient mutant can be rescued upon expression of ecotins from C. rectus and C. showae. In addition, the C. rectus and C. showae ecotins partially compensate for loss of N-glycosylation and increased protease susceptibility in the related pathogen, Campylobacter jejuni, thus implicating a similar role for these proteins in the native host to cope with the protease-rich environment of the oral cavity.


Assuntos
Campylobacter rectus/metabolismo , Campylobacter/metabolismo , Proteínas de Escherichia coli/genética , Proteínas Periplásmicas/genética , Inibidores de Serino Proteinase/metabolismo , Inibidores da Tripsina/metabolismo , Animais , Campylobacter/genética , Campylobacter rectus/genética , Células Cultivadas , Galinhas , Humanos , Neutrófilos/efeitos dos fármacos , Elastase Pancreática/antagonistas & inibidores , Homologia de Sequência , Inibidores de Serino Proteinase/genética , Inibidores de Serino Proteinase/farmacologia , Inibidores da Tripsina/farmacologia
4.
Shokuhin Eiseigaku Zasshi ; 61(4): 126-131, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-33012766

RESUMO

Campylobacter is one of the most important causes of food-borne infectious diseases. Antibiotics are rarely needed to treat campylobacteriosis, but occasionally used in severe or prolonged cases. Consumption of contaminated bovine liver is a source of campylobacteriosis. Bovine liver can be contaminated with Campylobacter on the surface and inside by the bile at slaughterhouses. Therefore, we investigated the current prevalence and characteristics of Campylobacter in bovine bile at a slaughterhouse. Campylobacter was isolated from 35.7% (55/154) of bile samples. C. jejuni and C. fetus were the two most frequent species. High antimicrobial resistant rates in C. jejuni were observed against tetracycline (63.0%) and ciprofloxacin (44.4%). Multi-locus sequence typing divided C. jejuni isolates (27 isolates) into 12 sequence types (STs) in which ST806 was the most frequent ST and accounted for 37.0%. All C. fetus were identified as C. fetus subsp. fetus which can cause systemic infections. High antimicrobial resistant rates in C. fetus were observed against ciprofloxacin (66.6%), streptomycin (58.3%) and tetracycline (33.3%). All the C. fetus isolates were divided into two STs, ST3 (16 isolates) and ST6 (8 isolates). Of the 16 ST3 isolates, 15 (93.8%) were resistant to both streptomycin and ciprofloxacin. Our data shows high prevalence of Campylobacter in bovine bile and their high rates of antimicrobial resistance. Preventing bile contamination of bovine liver at slaughterhouses is thus considered to be one of control measures to reduce the risk of Campylobacter infections.


Assuntos
Bile , Campylobacter , Vesícula Biliar , Animais , Anti-Infecciosos/farmacologia , Bile/microbiologia , Campylobacter/classificação , Campylobacter/efeitos dos fármacos , Campylobacter/genética , Campylobacter/isolamento & purificação , Bovinos , Farmacorresistência Bacteriana , Microbiologia de Alimentos , Vesícula Biliar/microbiologia , Tipagem de Sequências Multilocus , Prevalência
5.
PLoS One ; 15(8): e0237541, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32834007

RESUMO

There is growing interest in exploring the chickens' intestinal microbiota and understanding its interactions with the host. The objective is to optimize this parameter in order to increase the productivity of farm animals. With the goal to isolate candidate probiotic strains, specific culturomic methods were used in our study to culture commensal bacteria from 7-days old chicks raised in two farms presenting long history of high performance. A total of 347 isolates were cultured, corresponding to at least 64 species. Among the isolates affiliated to the Firmicutes, 26 had less than 97% identity of their partial 16S sequence with that of the closest described species, while one presented less than 93% identity, thus revealing a significant potential for new species in this ecosystem. In parallel, and in order to better understand the differences between the microbiota of high-performing and low-performing animals, caecal contents of animals collected from these two farms and from a third farm with long history of low performance were collected and sequenced. This compositional analysis revealed an enrichment of Faecalibacterium-and Campylobacter-related sequences in lower-performing animals whereas there was a higher abundance of enterobacteria-related sequences in high-performing animals. We then investigated antibiosis activity against C. jejuni ATCC 700819 and C. jejuni field isolate as a first phenotypic trait to select probiotic candidates. Antibiosis was found to be limited to a few strains, including several lactic acid bacteria, a strain of Bacillus horneckiae and a strain of Escherichia coli. The antagonist activity depended on test conditions that mimicked the evolution of the intestinal environment of the chicken during its lifetime, i.e. temperature (37°C or 42°C) and oxygen levels (aerobic or anaerobic conditions). This should be taken into account according to the stage of development of the animal at which administration of the active strain is envisaged.


Assuntos
Infecções por Campylobacter/microbiologia , Infecções por Campylobacter/veterinária , Campylobacter/isolamento & purificação , Ceco/microbiologia , Galinhas/microbiologia , Microbioma Gastrointestinal , Doenças das Aves Domésticas/epidemiologia , Envelhecimento , Animais , Campylobacter/genética , Técnicas de Cultura de Células/métodos , Fazendas , Doenças das Aves Domésticas/microbiologia
6.
Int J Food Microbiol ; 334: 108830, 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-32841810

RESUMO

The aim of this study was to determine the pathogenic markers associated with Campylobacter infection in humans. A total of 104 Campylobacter isolates obtained from poultry and humans were examined for the presence of nine virulence genes and their ability to adhere to, invade and produce cytotoxin were defined using HeLa cells. The diversity of the Campylobacter spp. isolates was studied based on sequencing of the SVR-region of flaA gene. Altogether 45 flaA-SVR alleles were identified among 104 Campylobacter isolates of poultry and human origin. All Campylobacter isolates possessed flaA, cadF and racR genes involved in adherence. Accordingly, all poultry and human isolates exhibited adherence towards HeLa cells at mean levels of 0.95% and 0.82% of starting viable inoculum, respectively. The genes involved in invasion (iam and pldA) and cytotoxin production (cdtA, cdtB and cdtC) were also widely distributed among the human and poultry Campylobacter isolates. Significantly higher invasiveness was observed for poultry isolates (mean level of 0.002% of starting bacterial inoculum) compared to human isolates (0.0005%). Interestingly the iam gene, associated with invasion, was more common in human (100%) than poultry (84%) isolates, and the poultry isolates lacking the iam gene showed a marked reduction in their ability to invade HeLa cells. Moreover, virB11 was present in 22% of the poultry and 70.4% of the human isolates. Strains lacking virB11 showed a slight reduction in invasion, however in the absence of iam even the poultry isolates containing virB11 were unable to invade HeLa cells. The mean cytotoxicity of Campylobacter isolates from poultry and human was 26.7% and 38.7%, respectively. Strains missing both the cdtB and cdtC genes were non-cytotoxic compared to strains containing all three cdtABC genes, which were the most cytotoxic among the C. jejuni and C. coli isolates from both sources. No cytotoxic effect was observed in only 4% of poultry and 5.6% of human isolates.


Assuntos
Infecções por Campylobacter/microbiologia , Campylobacter/isolamento & purificação , Campylobacter/patogenicidade , Aves Domésticas/microbiologia , Animais , Proteínas de Bactérias/genética , Campylobacter/genética , Células HeLa , Humanos , Polônia , Virulência/genética , Fatores de Virulência/genética
7.
Am J Trop Med Hyg ; 103(3): 1266-1269, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32524948

RESUMO

Campylobacter has emerged as a potential important cause of childhood morbidity in sub-Saharan Africa. Biannual mass azithromycin distribution has previously been shown to reduce all-cause child mortality in sub-Saharan Africa. We conducted a randomized controlled trial in Burkina Faso in which children were randomized in a 1:1 fashion to a 5-day course of azithromycin or placebo to investigate the effect of oral antibiotics on the gut microbiome. We evaluated the changes in the gut microbiome of preschool children treated with azithromycin using metagenomic DNA sequencing. We found that three Campylobacter species were reduced with azithromycin treatment compared with placebo. These results were consistent with other studies that have shown decreases in Campylobacter species after azithromycin treatment, generating the hypothesis that a decrease in Campylobacter may contribute to observations of reduction in mortality following azithromycin distribution.


Assuntos
Antibacterianos/uso terapêutico , Azitromicina/uso terapêutico , Infecções por Campylobacter/mortalidade , Campylobacter/isolamento & purificação , Microbioma Gastrointestinal , Burkina Faso/epidemiologia , Campylobacter/genética , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Mortalidade da Criança , Pré-Escolar , Humanos , Lactente , Metagenômica , Análise de Sequência de DNA
8.
J Appl Microbiol ; 129(5): 1173-1184, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32416023

RESUMO

AIMS: Campylobacter sp. are important causes of reproductive disease in ruminants worldwide. Although healthy bulls are well-known carriers for infection of cows, the role of rams as a potential source for infecting ewes is unclear. This study aimed to determine prevalence, species distribution, genetic diversity and antimicrobial susceptibility profiles of Campylobacter sp. isolated from the preputial cavity of healthy rams. METHODS AND RESULTS: The material of this prospective study comprised 191 swab samples taken from the preputial cavity of healthy rams. Enrichment and membrane filtration were employed for the isolation of Campylobacter. Presumptive isolates were confirmed as Campylobacter by phenotypic and molecular tests. 16S rRNA gene sequence analysis was used for the definitive identification of the isolates at species level, and genotyping was performed using pulsed-field gel electrophoresis (PFGE). The susceptibility of the Campylobacter sp. isolates to various antibiotics was determined by the disk diffusion test. In all, 27 of the 191 (14·13%) swab samples were found to be positive for Campylobacter sp. (28 isolates were recovered in total). Per phenotypic and genotypic analyses, one isolate was identified as Campylobacter mucosalis and the remaining 27 isolates were identified as Campylobacter sputorum bv. faecalis. The PFGE analysis of the C. sputorum biovar faecalis isolates produced 17 clusters and 24 different pulsotypes, indicating high genetic heterogeneity. All 28 isolates were found to be susceptible to all of the antibiotics tested. CONCLUSIONS: Healthy rams may be an important reservoir of different Campylobacter species in the preputium. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrated for the first time that healthy rams can carry different Campylobacter sp. including genetically diverse C. sputorum bv. faecalis and C. mucosalis in the preputial cavity. Further investigation on the potential implication of this finding on sheep reproductive health (e.g. infectious infertility, and abortion) and overall epidemiology of Campylobacter may be warranted.


Assuntos
Antibacterianos/farmacologia , Infecções por Campylobacter/veterinária , Campylobacter/efeitos dos fármacos , Campylobacter/genética , Doenças dos Ovinos/microbiologia , Animais , Campylobacter/classificação , Campylobacter/isolamento & purificação , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Portador Sadio/microbiologia , Portador Sadio/veterinária , Prepúcio do Pênis/microbiologia , Variação Genética , Masculino , Estudos Prospectivos , RNA Ribossômico 16S/genética , Ovinos , Doenças dos Ovinos/epidemiologia , Carneiro Doméstico , Turquia/epidemiologia
9.
Food Microbiol ; 90: 103455, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32336358

RESUMO

The present pilot study aimed at evaluating air sampling as a novel method for monitoring Campylobacter in poultry farms. We compared the bacteriological isolation of Campylobacter from boot swabs and air filter samples using ISO 10272-1:2017. A secondary aim was to evaluate the use of molecular methods, i.e. real time PCR, on the same sample set. Samples from 44 flocks from five European countries were collected, and included air samples, in parallel with boot swabs. Campylobacter spp. was isolated from seven of 44 boot swabs from three of five partners using the enrichment method. Two of these positive boot swab samples had corresponding positive air samples. Using enrichment, one positive air sample was negative in the corresponding boot swabs, but Campylobacter spp. was isolated from direct plating of the boot swab sample. One partner isolated Campylobacter spp. from six of 10 boot swabs using direct plating. Overall, 33 air filter samples were screened directly with PCR, returning 14 positive results. In conclusion, there was a lack of correspondence between results from analysis of boot swabs and air filters using ISO 10272-1:2017. In contrast, the combination of air filters and direct real-time PCR might be a way forward. Despite the use of the detailed ISO protocols, there were still sections that could be interpreted differently among laboratories. Air sampling may turn into a multi-purpose and low-cost sampling method that may be integrated into self-monitoring programs.


Assuntos
Microbiologia do Ar/normas , Infecções por Campylobacter/veterinária , Campylobacter/isolamento & purificação , Galinhas/microbiologia , Doenças das Aves Domésticas/prevenção & controle , Animais , Campylobacter/genética , Europa (Continente) , Fazendas/estatística & dados numéricos , Fezes/microbiologia , Internacionalidade , Projetos Piloto , Aves Domésticas/microbiologia , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/transmissão
10.
PLoS One ; 15(3): e0230390, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32176736

RESUMO

The aim of the study was to detect and genetically characterize Arcobacter butzleri in pet red-footed tortoises suspected for Campylobacter spp., using molecular techniques. A written consent from tortoise owners was obtained, after explaining the advantages of the research to tortoise owners of Grenada. Fecal samples were collected from 114 tortoises from five parishes of the country and cultured for Campylobacter spp. using selective culture techniques. A. butzleri was isolated from 4.39% of pet tortoises. Total thirteen isolates were obtained; all identified as A. butzleri by a universal and a species-specific Polymerase Chain Reaction (PCR) and direct sequencing. Genetic characterization of these isolates was performed based on Enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) that generated eight different genetic fingerprints with a discriminatory power of 0.91. Campylobacter species were not detected molecularly in any of the culture-positive samples. This is the first report of infection of pet tortoises in Grenada, West Indies with A. butzleri. This study emphasizes on the risk of zoonotic transmission of A. butzleri by exotic pets, which is a serious concern for public health.


Assuntos
Arcobacter/genética , Campylobacter/genética , Sequências Repetitivas de Ácido Nucleico/genética , Tartarugas/microbiologia , Animais , Campylobacter/isolamento & purificação , Impressões Digitais de DNA/métodos , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Fezes/microbiologia , Tartarugas/genética
11.
Mikrobiyol Bul ; 54(1): 11-25, 2020 Jan.
Artigo em Turco | MEDLINE | ID: mdl-32050875

RESUMO

The aim of this study was to investigate the frequency of Campylobacter species, to detect the antibiotic resistance profiles and the virulence genes and to determine the clonal proximity of the isolates in the samples of cutting board, slaughterhouse waste water, wall, knife and carcass from three different slaughterhouses in Kayseri region. For this purpose, a total of 150 samples, 10 of each from knife, wall, cutting board, carcass smear sample and slaughterhouse wastewater were collected from each of the three types of slaughterhouses in 2018 in Kayseri. For the isolation of the Campylobacter species, following preenrichment, the suspensions were inoculated onto modified charcoal cefoperazone desoxycholate (CCD) agar and were incubated at 37°C under microaerophilic condition for 48-72 hours. Suspicious colonies with gray-white color were recovered and subjected to phenotypical (Gram staining, oxidase, catalase test, and motion test) tests. Multiplex polymerase chain reaction (mPCR) was used for the molecular identification of the Campylobacter species. Antimicrobial susceptibilities of the isolates identified at the species level were detected by using the disk diffusion test and antibiotic gradient test. Virulence genes (iam, cadF, cdtA, flaA, ceuE, cdtC, cdtB and virB11) among the isolates were evaluated by PCR. The molecular typing of the isolates determined at species level was performed by Enterobacterial Repetitive Intergenic Consensus PCR (ERIC-PCR). In the study, 17 (11.3%) of the 150 samples taken from the slaughterhouse were found to be suspicious in terms of Campylobacter spp. and as a result of phenotypic identification tests, all of the isolates were verified as Campylobacter spp.. As a result of mPCR; eight of the isolates were identified as Campylobacter jejuni, eight as Campylobacter fetus and one as Campylobacter coli. The isolation of the Campylobacter species from different sources was found to be higher in slaughterhouse wastewater than those of others (p<0.001) and the difference in the proportional distribution of the Campylobacter species obtained from various sources was statistically significant (p<0.05). As a result of the disk diffusion test, while, all C.jejuni isolates were resistant to ciprofloxacin, 87.5%, 25%, 25% and 12.5% of C.jejuni isolates were resistant to enrofloxacin, neomycin, amoxicillin/clavulanic acid, and erythromycin, respectively. In addition, 25%, 25% and 12.5% of C.fetus isolates were resistant to amoxicillin/clavulanic acid, neomycin and gentamicin, respectively. C.coli isolate was not resistant to any of the antibiotics tested. Antibiotic gradient test results were found to be compatible with the disc diffusion test results. One of the virulence genes examined, virB11, was not detected in any of the isolates. Moreover, iam gene was not present in C.fetus and C.coli isolates, but only in one C.jejuni isolate. The flaA gene was detected in six C.jejuni isolates. C.coli isolate and seven C.jejuni and seven C.fetus isolates were positive in terms of the cdtC gene. The cdtA, cdtB, ceuE and cadF genes were found to be positive in all C.jejuni isolates. All isolates analyzed in the study demonstrated different ERIC-PCR profiles. In conclusion, it was shown that Campylobacter strains isolated from slaughterhouses were resistant to the most of the current antibiotics. Moreover, the presence of highly virulent Campylobacters in the slaughterhouse environment threatens public health due to the risk of contamination of the humans via carcasses and foods. Therefore, it is recommended that strict hygiene rules should be followed to reduce Campylobacter species contamination in slaughterhouses.


Assuntos
Campylobacter , Virulência , Matadouros , Antibacterianos/farmacologia , Campylobacter/efeitos dos fármacos , Campylobacter/genética , Campylobacter/patogenicidade , Humanos , Especificidade da Espécie , Virulência/genética
12.
Epidemiol Infect ; 148: e13, 2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-32000879

RESUMO

In December 2016, Public Health England investigated an outbreak of campylobacteriosis in North West England, with 69 cases in total. Epidemiological, microbiological and environmental investigations associated the illness with the consumption of unpasteurised cows' milk from Farm X, where milk was predominantly sold from a vending machine. Campylobacter was detected in milk samples which, when sequenced, were identical in sequence type as pathogens isolated from cases (Clonal Complex ST-403, Sequence Type 7432). The farm was served with a Hygiene Emergency Prohibition Order to prevent further cases. To our knowledge, this is the first outbreak of campylobacter associated with unpasteurised milk in England since 1996. Our findings highlighted several important lessons, including that the current testing regime in England for unpasteurised milk is not fit for purpose and that the required warning label should include additional wording, underscoring the risk to vulnerable groups. There has been a substantial increase in both the volume of unpasteurised milk consumed in England and the use of vending machines to sell unpasteurised milk over the last 10 years, making unpasteurised milk more readily accessible to a wider population. The evidence generated from outbreaks like this is therefore critical and should be used to influence policy development.


Assuntos
Infecções por Campylobacter/epidemiologia , Campylobacter/isolamento & purificação , Surtos de Doenças , Contaminação de Alimentos , Doenças Transmitidas por Alimentos/epidemiologia , Leite/microbiologia , Adolescente , Adulto , Idoso , Animais , Campylobacter/classificação , Campylobacter/genética , Bovinos , Criança , Pré-Escolar , Inglaterra/epidemiologia , Feminino , Humanos , Lactente , Masculino , Técnicas Microbiológicas , Pessoa de Meia-Idade , Tipagem Molecular , Estudos Retrospectivos , Análise de Sequência de DNA , Adulto Jovem
13.
Vet Microbiol ; 241: 108567, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31928704

RESUMO

The aim of this study was to investigate the occurrence and diversity of Campylobacter species in chelonians. From July 2016 to September 2017, a total of 452 individuals from a large variety of tortoises (n = 366) and turtles/terrapins (n = 86) kept in private collections and breeding centres, wildlife rescue centres, zoos, pet shops, and veterinary clinics from Northern Italy was sampled and subjected to microbiological examination. Campylobacter genus and species confirmation was performed by single and multiplex PCRs. Out of 452 samples, five (1.1%) tested positive: three for C. iguaniorum (two Testudo graeca and one Testudo hermanni), one for C. fetus subsp. testudinum (Stigmochelys pardalis) and one for C. geochelonis (Testudo hermanni). This study suggests that Campylobacter spp. are not common in chelonians, but a variety of species can be detected in these hosts, including those potentially pathogenic for humans. Further studies are needed to understand the epidemiology and the pathogenic potential for both animals and humans of reptile-associated Campylobacter spp.


Assuntos
Infecções por Campylobacter/veterinária , Campylobacter/fisiologia , Tartarugas/microbiologia , Animais , Animais de Zoológico , Campylobacter/classificação , Campylobacter/genética , Campylobacter/patogenicidade , Infecções por Campylobacter/microbiologia , DNA Bacteriano/análise , DNA Bacteriano/isolamento & purificação , Reservatórios de Doenças , Feminino , Itália , Reação em Cadeia da Polimerase Multiplex/veterinária , Animais de Estimação , Zoonoses/microbiologia
14.
PLoS One ; 15(1): e0227500, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31923228

RESUMO

A new species of the Campylobacter genus is described, isolated from the preputial mucosa of bulls (Bos taurus). The five isolates obtained exhibit characteristics of Campylobacter, being Gram-negative non-motile straight rods, oxidase positive, catalase negative and microaerophilic. Phenotypic characteristics and nucleotide sequence analysis of 16S rRNA and hsp60 genes demonstrated that these isolates belong to a novel species within the genus Campylobacter. Based on hsp60 gene phylogenetic analysis, the most related species are C. ureolyticus, C. blaseri and C. corcagiensis. The whole genome sequence analysis of isolate FMV-PI01 revealed that the average nucleotide identity with other Campylobacter species was less than 75%, which is far below the cut-off for isolates of the same species. However, whole genome sequence analysis identified coding sequences highly homologous with other Campylobacter spp. These included several virulence factor coding genes related with host cell adhesion and invasion, transporters involved in resistance to antimicrobials, and a type IV secretion system (T4SS), containing virB2-virB11/virD4 genes, highly homologous to the C. fetus subsp. venerealis. The genomic G+C content of isolate FMV-PI01 was 28.3%, which is one of the lowest values reported for species of the genus Campylobacter. For this species the name Campylobacter portucalensis sp. nov. is proposed, with FMV-PI01 (= LMG 31504, = CCUG 73856) as the type strain.


Assuntos
Campylobacter/genética , Pênis/microbiologia , Animais , Proteínas de Bactérias/classificação , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Campylobacter/classificação , Campylobacter/isolamento & purificação , Campylobacter/metabolismo , Bovinos , Chaperonina 60/classificação , Chaperonina 60/genética , Chaperonina 60/metabolismo , Epitélio/microbiologia , Genótipo , Masculino , Fenótipo , Filogenia , RNA Ribossômico 16S/química , RNA Ribossômico 16S/classificação , RNA Ribossômico 16S/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Sequenciamento Completo do Genoma
15.
Can J Microbiol ; 66(3): 171-185, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31721603

RESUMO

Intensive poultry production due to public demand raises the risk of contamination, creating potential foodborne hazards to consumers. The prevalence and microbial load of the pathogens Campylobacter, Salmonella, Staphylococcus aureus, and Escherichia coli was determined by standard methods at the farm level. After disinfection, swab samples collected from wall crevices, drinkers, and vents were heavily contaminated, as accumulated organic matter and dust likely protected the pathogens from the disinfectants used. The annex floor also showed high microbial concentrations, suggesting the introduction of pathogens from external environments, highlighting the importance of erecting hygiene barriers at the entrance of the main shed. Therefore, pathogen control measures and proper application of disinfectants are recommended as intervention strategies. Additionally, quantitative polymerase chain reaction (qPCR) was evaluated as a quantification tool. qPCR showed limitations with samples containing low microbial counts because of the low detection limit of the method. Thus, bacterial pre-enrichment of test samples may be necessary to improve the detection of pathogens by qPCR.


Assuntos
Campylobacter/isolamento & purificação , Escherichia coli/isolamento & purificação , Doenças das Aves Domésticas/microbiologia , Salmonella/isolamento & purificação , Staphylococcus aureus/isolamento & purificação , Criação de Animais Domésticos/estatística & dados numéricos , Animais , Campylobacter/classificação , Campylobacter/genética , Galinhas , Escherichia coli/classificação , Escherichia coli/genética , Fazendas/estatística & dados numéricos , Contaminação de Alimentos/análise , Nova Zelândia/epidemiologia , Doenças das Aves Domésticas/epidemiologia , Salmonella/classificação , Salmonella/genética , Staphylococcus aureus/classificação , Staphylococcus aureus/genética
16.
Lett Appl Microbiol ; 71(1): 102-107, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31560126

RESUMO

Sixteen sites in the watershed of the South Fork of the Broad River (SFBR) in Northeastern Georgia, USA, were sampled in two seasons to detect Campylobacter. Sites were classified as mostly influenced by forest, pasture, wastewater pollution control plants (WPC) or mixed use. Sampling was repeated in the late spring and late fall for 2 years for a total of 126 samples. Free-catch water and sediment grab samples were taken at each site; Moore's swabs were placed for up to 3 days at most sites. A total of 56 isolates of thermophilic Campylobacter were recovered. Thirteen samplings were positive by two or three methods, and 26 samplings were positive by only one method; once by Moore's swab only and 25 times by free-catch water only. Campylobacter was detected at 58% of cattle pasture sites, 30% of forested sites and 81% of WPC sites. Twenty-one of the isolates carried antimicrobial resistance genes, mostly blaOXA-61. Free-catch water samples were more efficient than Moore's swabs or sediment samples for recovery of Campylobacter, which was more likely to be detected in streams near cattle pastures and human communities than in forested land. SIGNIFICANCE AND IMPACT OF THE STUDY: The role of environmental water in transmitting Campylobacter was investigated, and methods for recovery of the organism were compared. The sequence types of recovered Campylobacter correlated with adjacent land use without regard to the method used to isolate the organisms. Sequence types and antimicrobial resistance genes associated with cattle were most prevalent near pastures. Even though types were recurrent at a given site, types appeared to be lost or replaced as the water flowed downstream.


Assuntos
Antibacterianos/farmacologia , Campylobacter/genética , Sedimentos Geológicos/microbiologia , Rios/microbiologia , Resistência beta-Lactâmica/genética , Animais , Campylobacter/efeitos dos fármacos , Campylobacter/isolamento & purificação , Infecções por Campylobacter/tratamento farmacológico , Infecções por Campylobacter/transmissão , Bovinos , Georgia , Humanos , Estações do Ano , Águas Residuárias/microbiologia
17.
Vopr Pitan ; 88(5): 17-23, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31710783

RESUMO

Gastroenterocolitis caused by Campylobacter bacteria are the most common acute infectious zoonotic foodborne diseases. One of the important factors for the transmission of infection is contaminated dairy products, so the assessment of contamination of raw milk with Campylobacter is necessary to develop effective measures to suppress the growth of the pathogen and ensure the safety of products. The aim of the study was to assess the microbial characteristics of raw milk samples and the nature of their contamination with thermophilic bacteria of the Campylobacter genus. Material and methods. A total of 60 samples of raw milk from the central regions of the Russian Federation and 48 experimentally infected samples of raw milk were studied. To assess the microbial contamination of milk, the number of extraneous microflora was determined, including coliform bacteria (CFB). The identification and quantification of bacteria of the genus Campylobacter was carried out by cultural methods in comparison with quantitative PCR assay. For PCR, primers were used that detected the speciesspecific sequence of C. jejuni 16s rRNA, the presence of the cytotoxic toxin gene cdtB and the invasion gene ciaB. Results and discussion. A significant part of the samples of raw milk (31.6%) was characterized by high levels of microbial contamination exceeding 106 CFU/cm3. Gram-negative bacteria were the dominant type of bacterial microflora, their levels were comparable with the detected values of the total number of microorganisms. Coliform bacteria were found in all studied samples, and their content in 90% of the samples reached 105 CFU/cm3, and in some samples - 107 CFU/cm3. Campylobacter spp. detection rate in raw milk was 8.3%, and their number ranged from 0.1 to 100 CFU/cm3 (average 2.0×10 CFU/cm3). The isolated strains of campylobacters were identified as a C. jejuni species. In the study of the microbial background of the examined samples of raw milk, a comparative analysis of their contamination by campylobacters by rti-PCR was simultaneously carried out. The majority of samples (over 60%) were positive for the presence of 16s rRNA genomic sequence, and they were characterized by the highest values of total bacterial contamination and the amount of coliforms. The use of a multi-primer approach (simultaneous testing for the presence of 16s rRNA and the gene of cytoletal toxin cdtB C. jejuni) reduced the number of positive cases of Campylobacter DNA detection to 16.6%, which suggests a greater informative value of the cdtB gene for the detection of viable, including uncultivated cells. An indicative assessment of the results in a quantitative format showed levels of 104-106.5 genomic equivalents of the DNA in 1 cm3, suggesting the possible presence of viable Campylobacter cells in the tested probes with a significantly greater frequency than that established by cultural method. Conclusion. At low levels of Сampylobacter contamination the microbiological methods do not provide reliable detection of the pathogen due to massive contamination of raw milk by extraneous microflora. Campylobacter spp. were detected by the culture method in 8.3% of cases, while the use of multi-primer PCR assay with cdtB and ciaB genes can double the detection of C. jejuni in raw milk samples.


Assuntos
Campylobacter , Contaminação de Alimentos , Microbiologia de Alimentos , Leite/microbiologia , Reação em Cadeia da Polimerase , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Animais , Campylobacter/classificação , Campylobacter/genética
18.
Euro Surveill ; 24(43)2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31662159

RESUMO

BackgroundCampylobacter is a leading global cause of bacterial gastroenteritis, motivating research to identify sources of human infection. Population genetic studies have been increasingly applied to this end, mainly using multilocus sequence typing (MLST) data.ObjectivesThis review aimed to summarise approaches and findings of these studies and identify best practice lessons for this form of genomic epidemiology.MethodsWe systematically reviewed publications using MLST data to attribute human disease isolates to source. Publications were from January 2001, when this type of approach began. Searched databases included Scopus, Web of Science and PubMed. Information on samples and isolate datasets used, as well as MLST schemes and attribution algorithms employed, was obtained. Main findings were extracted, as well as any results' validation with subsequent correction for identified biases. Meta-analysis is not reported given high levels of heterogeneity.ResultsOf 2,109 studies retrieved worldwide, 25 were included, and poultry, specifically chickens, were identified as principal source of human infection. Ruminants (cattle or sheep) were consistently implicated in a substantial proportion of cases. Data sampling and analytical approaches varied, with five different attribution algorithms used. Validation such as self-attribution of isolates from known sources was reported in five publications. No publication reported adjustment for biases identified by validation.ConclusionsCommon gaps in validation and adjustment highlight opportunities to generate improved estimates in future genomic attribution studies. The consistency of chicken as the main source of human infection, across high income countries, and despite methodological variations, highlights the public health importance of this source.


Assuntos
Infecções por Campylobacter/diagnóstico , Campylobacter/genética , Galinhas/microbiologia , Reservatórios de Doenças/microbiologia , Tipagem de Sequências Multilocus/métodos , Ruminantes/microbiologia , Animais , Campylobacter/classificação , Campylobacter/isolamento & purificação , Infecções por Campylobacter/microbiologia , Infecções por Campylobacter/veterinária , Bovinos , DNA Bacteriano/genética , Humanos , Ovinos
19.
Artigo em Inglês | MEDLINE | ID: mdl-31480468

RESUMO

BACKGROUND: Type-2-Diabetes (T2D) and Periodontitis are major inflammatory diseases. However, not much is known about the specific subgingival microbiota in Mexicans with diabetes and metabolic dysbiosis. The aim of this study was to describe the subgingival microbiota of Mexicans with T2D and the different periodontal and metabolic conditions, through "Checkerboard" DNA-DNA hybridization. METHODS: Subjects were divided into two groups-periodontal-health (PH) (PH_non-T2D; n = 59, PH_T2D; n = 14) and generalized-periodontitis (GP) (GP_non-T2D; n = 67, GP_T2D; n = 38). Obesity (BMI ≥ 30 kg/m2) and serum levels of glycated-hemoglobin (HbA1c), total-lipids, triglycerides, total-cholesterol, high-density-lipids, and low-density-lipids were measured for the T2D individuals. Subgingival microbial identification was processed for 40 species through DNA-probes. RESULTS: Subjects with T2D harbored significantly higher mean total levels (PH: p < 0.001, and GP_NS), a lower proportion of "red" complex (GP: p < 0.01), a higher proportion of "yellow" (GP; p < 0.001), and "orange" (GP; p < 0.01) complex than the non-T2D. GP_T2D individuals exhibited a greater proportion of putative-species-Campylobacter gracilis and S. constellatus (p < 0.001), and Parvimonas micra and Prevotella nigrescens (p < 0.01), than GP_non-T2D. T2D individuals with HbA1c > 8% had presented significantly higher mean pocket-depth and higher levels of G. morbillorum (p < 0.05) and those with obesity or dyslipidemia harbored higher levels, prevalence, or proportion of Streptococcus sp., Actinomyces sp., and Capnocytophaga sp. CONCLUSIONS: T2D individuals harbored a particular microbial profile different to non-T2D microbiota. Metabolic control was related to dysbiosis of microbiota-HbA1c>8% related to periodontitis and obesity or dyslipidemia with the predominance of saccharolytic bacteria, irrespective of their periodontal condition.


Assuntos
Bactérias/isolamento & purificação , Diabetes Mellitus Tipo 2/microbiologia , Doenças da Gengiva/microbiologia , Microbiota , Periodontite/microbiologia , Adulto , Bactérias/genética , Campylobacter/genética , Feminino , Humanos , Masculino , México , Pessoa de Meia-Idade , Hibridização de Ácido Nucleico
20.
Sci Rep ; 9(1): 11692, 2019 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-31406214

RESUMO

Benthic foraminifera are known to play an important role in marine carbon and nitrogen cycles. Here, we report an enrichment of sulphur cycle -associated bacteria inside intertidal benthic foraminifera (Ammonia sp. (T6), Haynesina sp. (S16) and Elphidium sp. (S5)), using a metabarcoding approach targeting the 16S rRNA and aprA -genes. The most abundant intracellular bacterial groups included the genus Sulfurovum and the order Desulfobacterales. The bacterial 16S OTUs are likely to originate from the sediment bacterial communities, as the taxa found inside the foraminifera were also present in the sediment. The fact that 16S rRNA and aprA -gene derived intracellular bacterial OTUs were species-specific and significantly different from the ambient sediment community implies that bacterivory is an unlikely scenario, as benthic foraminifera are known to digest bacteria only randomly. Furthermore, these foraminiferal species are known to prefer other food sources than bacteria. The detection of sulphur-cycle related bacterial genes in this study suggests a putative role for these bacteria in the metabolism of the foraminiferal host. Future investigation into environmental conditions under which transcription of S-cycle genes are activated would enable assessment of their role and the potential foraminiferal/endobiont contribution to the sulphur-cycle.


Assuntos
Deltaproteobacteria/genética , Epsilonproteobacteria/genética , Foraminíferos/microbiologia , Gammaproteobacteria/genética , Enxofre/metabolismo , Simbiose/fisiologia , Bacteroidaceae/classificação , Bacteroidaceae/genética , Bacteroidaceae/isolamento & purificação , Campylobacter/classificação , Campylobacter/genética , Campylobacter/isolamento & purificação , Código de Barras de DNA Taxonômico/métodos , DNA Bacteriano/genética , Deltaproteobacteria/classificação , Deltaproteobacteria/isolamento & purificação , Epsilonproteobacteria/classificação , Epsilonproteobacteria/isolamento & purificação , Foraminíferos/fisiologia , Gammaproteobacteria/classificação , Gammaproteobacteria/isolamento & purificação , Sedimentos Geológicos/química , Sedimentos Geológicos/microbiologia , Mar do Norte , Filogenia , Análise de Componente Principal , RNA Ribossômico 16S/genética , Água do Mar/química , Água do Mar/microbiologia , Serina Endopeptidases/genética , Enxofre/química
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