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Frontiers in Microbiology 2022The is a globally emerging foodborne and zoonotic pathogen that can cause diarrhea in humans. It is relatively homogenous and clearly distinguishes the group from other...
The is a globally emerging foodborne and zoonotic pathogen that can cause diarrhea in humans. It is relatively homogenous and clearly distinguishes the group from other . () is a heterogeneous species and little is known about its genomic characterization in China. This study aims to determine the genetic and plasmid features of based on whole-genome sequence (WGS). Average Nucleotide Identity (ANI) and DNA-DNA hybridization (DDH) were used for the species classification for 90 initially identified strains. One complete genome and 42 draft genomes were obtained by whole genome sequencing. The genomic characteristics were determined using various bioinformatics software. The genomes of the strains examined were estimated to vary from 1.81 to 2.28 Mb in length, with a G + C content of around 27%. ANI and DDH results indicated that 90 initially identified strains should be reclassified into four new species (ANI > 96% or DDH > 70%). Two clades (four subclades) were identified among 90 genomes with the phylogenetic analysis. The phylogenetic tree indicated these 90 genomes exhibited a high intra-species genomic diversity. No clustering was assorted with the host or geographic location among these genomes. Aminoglycoside resistance genes, such as , , , , and streptothricin resistance gene were detected in the chromosomes from a third of the Chinese strains. Virulence-related genes were identified in all the sequenced strains. A novel large multiple drug-resistant plasmid (named pCNAC48 with 161,992 bp in length) was identified in strain ICDCAC48. Two antibiotic-resistance islands were found in the plasmid with lengths of 7,950 and 25,137 bp and G + C content of 38.23 and 32.39%, respectively. The drug resistance genes and some transposable elements were cross-distributed among the islands in the plasmid. Antimicrobial susceptibility tests indicated these resistance genes in the plasmid were functional. Plasmid conjugation and curing experiments proved pCNAC48 was stable in strain ICDCAC48. It was the first identified multiple drug resistance plasmid in .
PubMed: 36212879
DOI: 10.3389/fmicb.2022.984450 -
Journal of Food Protection Jan 2021Arcobacter species are gram-negative rods that have been implicated in food- and waterborne illness. Although various cultural isolation methods have been proposed, the...
ABSTRACT
Arcobacter species are gram-negative rods that have been implicated in food- and waterborne illness. Although various cultural isolation methods have been proposed, the current procedures are unable to fully suppress the growth of background microbiota present in food samples, which inhibits Arcobacter isolation. The purpose of this study was to develop a selective enrichment broth and chromogenic plating medium to detect three Arcobacter species that have been recognized as emerging foodborne pathogens: Arcobacter butzleri, Arcobacter cryaerophilus, and Arcobacter skirrowii. The developed Nguyen-Restaino-Juárez (NRJ) Arcobacter detection system consists of a selective enrichment broth (NRJ-B) and a selective-differential plating medium (NRJ-M). The protocol of the detection method was determined by evaluating the growth of A. butzleri, A. cryaerophilus, and A. skirrowii under various temperatures (30, 35, and 42°C) and incubation (aerobic, microaerophilic, and anaerobic) conditions. Additionally, 47 Arcobacter strains and 39 non-Arcobacter strains were tested in inclusivity and exclusivity evaluations of NRJ-B and NRJ-M. Overall, the study determined that the optimal growth conditions of Arcobacter species using the NRJ Arcobacter detection system were aerobic incubation at 30°C. NRJ-B supported good growth of A. butzleri, A. cryaerophilus, and A. skirrowii while effectively suppressing the growth of non-Arcobacter strains after 48 h. Furthermore, NRJ-M yielded 97.8% inclusivity and 100.0% exclusivity using the tested strains and resulted in salmon-pigmented Arcobacter colonies (1.0 to 1.5 mm in diameter) after 72 h. The novel protocol is the first to develop a chromogenic plating medium for the isolation of Arcobacter species. This simple and accurate test method would greatly contribute to understanding the distribution of pathogenic Arcobacter species in food samples.
Topics: Agar; Arcobacter; Culture Media
PubMed: 33411930
DOI: 10.4315/JFP-20-245 -
A Polyphasic and Taxogenomic Evaluation Uncovers as a Species Complex That Embraces Four Genomovars.Frontiers in Microbiology 2018The species is found in many food products of animal origin and is the dominating species in wastewater. In addition, it is associated with cases of farm animal and...
The species is found in many food products of animal origin and is the dominating species in wastewater. In addition, it is associated with cases of farm animal and human infectious diseases,. The species embraces two subgroups i.e., 1A (LMG 24291 = LMG 9904) and 1B (LMG 10829) that can be differentiated by their 16S rRNA-RFLP pattern. However, some authors, on the basis of the shared intermediate levels of DNA-DNA hybridization, have suggested abandoning the subgroup classification. This contradiction indicates that the taxonomy of this species is not yet resolved. The objective of the present study was to perform a taxonomic evaluation of the diversity of . Genomic information was used along with a Multilocus Phylogenetic Analysis (MLPA) and phenotypic characterization on a group of 52 temporally and geographically dispersed strains, coming from different types of samples and hosts from nine countries. The MLPA analysis showed that those strains formed four clusters (I-IV). Values of Average Nucleotide Identity (ANI) and DNA-DNA Hybridization (DDH) obtained between 13 genomes representing strains of the four clusters were below the proposed cut-offs of 96 and 70%, respectively, confirming that each of the clusters represented a different genomic species. However, none of the evaluated phenotypic tests enabled their unequivocal differentiation into species. Therefore, the genomic delimited clusters should be considered genomovars of the species . These genomovars could have different clinical importance, since only the cluster I included strains isolated from human specimens. The discovery of at least one stable distinctive phenotypic character would be needed to define each cluster or genomovar as a different species. Until then, we propose naming them "" (Cluster I = LMG 10229), "" (Cluster II = LMG 9065), " (Cluster III = LMG 24291) and "" (Cluster IV = LMG 29976).
PubMed: 29755434
DOI: 10.3389/fmicb.2018.00805 -
Veterinary Medicine and Science Jul 2022Arcobacter spp. has been considered an emerging foodborne pathogen and a hazard to human health. The dairy chain has been isolated from different sources; nevertheless,...
BACKGROUND
Arcobacter spp. has been considered an emerging foodborne pathogen and a hazard to human health. The dairy chain has been isolated from different sources; nevertheless, data on Arcobacter occurrence in raw milk and dairy products in Iran are still scant.
OBJECTIVE
The present study investigates the prevalence, antimicrobial susceptibility and the presence of virulence genes of Arcobacters species isolated from milk and dairy products.
METHODS
Then, a total of 350 raw milk samples and 400 dairy product samples were collected from dairy supply centers in Isfahan, Iran. Presumptive Arcobacter strains were obtained by enriching samples in Oxoid Arcobacter enrichment broth (AEB) followed by the filtration of enrichment product through 0.45-μm pore size membrane filters laid onto non-selective blood at 30°C under microaerophilic conditions. Molecular identification of Arcobacter cryaerophilus and A. butzleri was performed by Polymerase chain reaction (PCR) amplification of the 16S rRNA gene, followed by sequencing. The disc diffusion method was used to determine the antimicrobial susceptibility of isolates. Targeted resistance and virulence genes were detected using multiplex PCR.
RESULTS
The results show a low recovery rate of Arcobacter spp. in milk. Arcobacters were found in all types of milk, except raw camel milk, but were absent from all dairy products. Arcobacter butzleri was the predominant species in raw milk. Detection of virulence genes shows that all virulence genes targeted were found among A. butzleri, and six (cadF, cj1349, irgA, mviN, pldA, tlyA) were found among A. cryaerophilus. All A. butzleri strains and some A. cryaerophilus strains isolated from milk were resistant to amoxicillin-clavulanic acid and tetracycline. All A. cryaerophilus isolates from milk were susceptible to gentamycin, streptomycin, erythromycin and ciprofloxacin. The distribution of resistance genes in Arcobacter strains in milk shows that all isolates carried tet(O) and bla genes.
CONCLUSIONS
In conclusion, the results indicate a low recovery rate of Arcobacter spp. in milk and milk products. However, a significant number of Arcobacter strains with putative virulence genes may be potential pathogens for humans and an overall increase in Arcobacter resistance to first-line antibiotics. These results highlight the need for regular surveillance of Arcobacter strains in milk and milk products in Iran.
Topics: Animals; Anti-Bacterial Agents; Arcobacter; Drug Resistance, Microbial; Genotype; Humans; Milk; Multiplex Polymerase Chain Reaction; Prevalence; RNA, Ribosomal, 16S; Virulence Factors
PubMed: 35426255
DOI: 10.1002/vms3.800 -
Applied and Environmental Microbiology Aug 2015Even though dairy cows are known carriers of Arcobacter species and raw or minimally processed foods are recognized as the main sources of human Arcobacter infections in...
Even though dairy cows are known carriers of Arcobacter species and raw or minimally processed foods are recognized as the main sources of human Arcobacter infections in industrialized countries, data on Arcobacter excretion patterns in cows and in milk are scant. This study aimed to identify potentially pathogenic Arcobacter species in a dairy herd and to investigate the routes of Arcobacter transmission among animals and the potential sources of cattle infection and milk contamination. A strategy of sampling the same 50 dairy animals, feed, water, and milk every month for a 10-month period, as well as the sampling of quarter milk, animal teats, the milking environment, and animals living on the farm (pigeons and cats), was used to evaluate, by pulsed-field gel electrophoresis (PFGE), the characteristic patterns in animals, their living environment, and the raw milk they produced. Of the 463 samples collected, 105 (22.6%) were positive for Arcobacter spp. by culture examination. All the matrices except quarter milk and pigeon gut samples were positive, with prevalences ranging from 15 to 83% depending on the sample. Only three Arcobacter species, Arcobacter cryaerophilus (54.2%), A. butzleri (34.2%), and A. skirrowii (32.3%), were detected. PFGE analysis of 370 isolates from positive samples provided strong evidence of Arcobacter circulation in the herd: cattle likely acquire the microorganisms by orofecal transmission, either by direct contact or from the environment, or both. Water appears to be a major source of animal infection. Raw milk produced by the farm and collected from a bulk tank was frequently contaminated (80%) by A. butzleri; our PFGE findings excluded primary contamination of milk, whereas teats and milking machine surfaces could be sources of Arcobacter milk contamination.
Topics: Animals; Animals, Domestic; Arcobacter; Carrier State; Cats; Cattle; Columbidae; DNA Fingerprinting; Electrophoresis, Gel, Pulsed-Field; Environmental Microbiology; Food Contamination; Gram-Negative Bacterial Infections; Humans; Milk; Molecular Typing
PubMed: 26002896
DOI: 10.1128/AEM.01035-15 -
Journal of Food Protection Mar 2023Arcobacters are emerging pathogens that have been underestimated due to a lack of a standardized isolation method. The aim of this research was to evaluate the ability...
Arcobacters are emerging pathogens that have been underestimated due to a lack of a standardized isolation method. The aim of this research was to evaluate the ability to isolate Arcobacter butzleri, Arcobacter cryaerophilus, and Arcobacter skirrowii using two Arcobacter-specific culture detection systems: (i) the Houf broth and modified charcoal cefoperazone deoxycholate agar supplemented with cefoperazone, amphotericin B, and teicoplanin (HB/mCCDA+CAT), and (ii) the Nguyen-Restaino-Juárez Arcobacter enrichment broth and chromogenic agar (NRJ-B/M). Both detection systems were evaluated for productivity ratio, sensitivity, and specificity. As a result, the productivity ratio for both plating agars were >90%, which indicates that the selective agents used in the two plating agars did not inhibit Arcobacter growth. Moreover, sensitivity evaluations using artificially inoculated retail ground poultry (n = 780) determined that both detection systems were able to isolate A. butlzeri with >95% sensitivity at the 0.1 and 1.0-2.0 CFU/g detection level. The sensitivity in A. cryaerophilus isolation was higher for NRJ-B/M (78.0% at 0.1 CFU/g; 95.1% at 1.0-2.0 CFU/g) when compared with HB/mCCDA+CAT (34.1% at 0.1 CFU/g; 51.2% at 1.0-2.0 CFU/g). Both detection systems resulted in <50% sensitivity when isolating A. skirrowii at 0.1 and 1.0-2.0 CFU/g; however, the sensitivity for NRJ-B/M was significantly higher than HB/mCCDA+CAT. At the detection level of 5.0 CFU/g, both detection systems were able to isolate A. skirrowii with 100% sensitivity. Specificity comparisons using uninoculated ground poultry samples (n = 40) indicated the growth of background microbiota were significantly inhibited or could be easily differentiated on NRJ-B/M (90.0%, specificity) when compared with HB/mCCDA+CAT (30.0%, specificity). Overall, these results show that the NRJ-B/M detection system is a more sensitive and specific detection system when isolating Arcobacter spp. from ground chicken.
Topics: Animals; Poultry; Arcobacter; Agar; Cefoperazone
PubMed: 36916562
DOI: 10.1016/j.jfp.2023.100057 -
Antibiotics (Basel, Switzerland) Mar 2021spp. are emerging waterborne and foodborne zoonotic pathogens responsible for gastroenteritis in humans. In this work, we evaluated the occurrence and the antimicrobial...
spp. are emerging waterborne and foodborne zoonotic pathogens responsible for gastroenteritis in humans. In this work, we evaluated the occurrence and the antimicrobial resistance profile of isolates recovered from different aquatic sources. Besides, we searched for spp. in seaweeds and the corresponding seawater samples. Bacteriological and molecular methods applied to 100 samples led to the isolation of 28 isolates from 27 samples. The highest prevalence was detected in rivers followed by artificial ponds, streams, well waters, and spring waters. Seaweeds contained a higher percentage of than the corresponding seawater samples. The isolates were identified as (96.4%) and (3.6%). All the isolates showed a multi-drug resistance profile, being resistant to at least three different classes of antibiotics. Molecular analysis of genetic determinants responsible for tetracycline resistance in nine randomly chosen isolates revealed the presence of and/or This work confirms the occurrence and the continuous emergence of antibiotic-resistant strains in environmental samples; also, the presence of quinolone-resistant spp. in aquatic sources used for water supply and irrigation represents a potential risk for human health.
PubMed: 33802125
DOI: 10.3390/antibiotics10030288 -
Journal of Dairy Science Oct 2015Ricotta cheese is a ready-to-eat product with properties (pH >6.0, aw >0.98-0.99) and moisture content (75-80%) that may pose a risk to public health due to postprocess...
Ricotta cheese is a ready-to-eat product with properties (pH >6.0, aw >0.98-0.99) and moisture content (75-80%) that may pose a risk to public health due to postprocess contamination by several bacterial pathogens, including Arcobacters. The objective of the study was to evaluate the behavior of Arcobacter butzleri and Arcobacter cryaerophilus in ricotta cheese during its shelf life assuming postprocessing contamination. Two types of ricotta cheese, artisanal water buffalo (WB) and industrial cow milk ricotta cheese, were experimentally contaminated with A. butzleri and A. cryaerophilus and the count was monitored at 2 different temperatures (6°C and 12°C) during shelf life of 5 d for WB cheese and 22 d for industrial ricotta cheese. In WB ricotta cheese the A. butzleri count remained stable during the 5 d of storage at 6°C, whereas a moderate but significant decrease was observed in A. cryaerophilus count. The counts of both species increased when WB ricotta cheese was stored at 12°C. In industrial ricotta cheese stored at 6°C, a significant reduction was observed both in A. butzleri and A. cryaerophilus counts during the 22-d storage period; at 12°C storage, a count increase was observed for both Arcobacter species up to d 14 of storage after which the log cfu/g count resulted constant until d 22 of storage. The ability of A. butzleri and A. cryaerophilus to survive at 6°C and to grow at 12°C in ricotta cheese has significant food safety implications.
Topics: Animals; Arcobacter; Buffaloes; Cattle; Cheese; Food Microbiology; Food Safety; Species Specificity; Temperature
PubMed: 26233450
DOI: 10.3168/jds.2015-9560 -
Italian Journal of Food Safety Mar 2021Given that the number of foodborne illness outbreaks linked to the consumption of ready-to-eat vegetables has been widely documented and considering that data on the...
Given that the number of foodborne illness outbreaks linked to the consumption of ready-to-eat vegetables has been widely documented and considering that data on the occurrence of spp. in such foodstuffs are lacking, the aim of the present study was to evaluate the presence of spp. and the occurrence of virulence factors as well as to genotype spp. in ready-to-eat (RTE) vegetable samples, using cultural and biomolecular assays. spp. was detected in 16/110 (14.5%) samples, with being detected in 15/16 and in 1/16 isolates. PCRs aimed at the nine putative virulence genes demonstrated widespread distribution of such genes among and isolates. In addition, multilocus sequence type (MLST) analysis revealed a low genetic diversity within the arcobacters isolates. The results underline the need to develop an appropriate surveillance system based on biomolecular characterization for an integrated microbiological risk assessment of ready-toeat vegetables, and consequently of composite foods.
PubMed: 33907683
DOI: 10.4081/ijfs.2021.8585 -
Journal of Food Protection Jul 2009An enrichment PCR assay using species-specific primers was developed for the detection of Arcobacter butzleri, Arcobacter cryaerophilus, Arcobacter skirrowii, and...
An enrichment PCR assay using species-specific primers was developed for the detection of Arcobacter butzleri, Arcobacter cryaerophilus, Arcobacter skirrowii, and Arcobacter cibarius in chicken meat. Primers for A. cryaerophilus, A. skirrowii, and A. cibarius were designed based on the gyrA gene to amplify nucleic acid fragments of 212, 257, and 145 bp, respectively. The A. butzleri-specific primers were designed flanking a 203-bp DNA fragment in the 16S rRNA gene. The specificity of the four primer pairs was assessed by PCR analysis of DNA from a panel of Arcobacter species, related Campylobacter, Helicobacter species, and other food bacteria. The applicability of the method was then validated by testing 42 fresh retail-purchased chicken samples in the PCR assay. An 18-h selective preenrichment step followed by PCR amplification with the four Arcobacter primer sets revealed the presence of Arcobacter spp. in 85.7% of the retail chicken samples analyzed. A. butzleri was the only species present in 50% of the samples, and 35.7% of the samples were positive for both A. butzleri and A. cryaerophilus. A. skirrowii and A. cibarius were not detected in any of the chicken samples analyzed. The enrichment PCR assay developed is a specific and rapid alternative for the survey of Arcobacter contamination in meat.
Topics: Animals; Arcobacter; Base Sequence; Chickens; Colony Count, Microbial; Culture Media; DNA Primers; DNA, Bacterial; Food Contamination; Food Microbiology; Gene Amplification; Humans; Meat; Polymerase Chain Reaction; RNA, Ribosomal, 16S; Sensitivity and Specificity; Species Specificity
PubMed: 19681276
DOI: 10.4315/0362-028x-72.7.1491