-
Microorganisms May 2023, the most widespread species within the genus , is considered as an emerging pathogen causing gastroenteritis in humans. Here, we performed a comparative genome-wide...
, the most widespread species within the genus , is considered as an emerging pathogen causing gastroenteritis in humans. Here, we performed a comparative genome-wide analysis of 40 strains from Lithuania to determine the genetic relationship, pangenome structure, putative virulence, and potential antimicrobial- and heavy-metal-resistance genes. Core genome single nucleotide polymorphism (cgSNP) analysis revealed low within-group variability (≤4 SNPs) between three milk strains (RCM42, RCM65, RCM80) and one human strain (H19). Regardless of the type of input (i.e., cgSNPs, accessory genome, virulome, resistome), these strains showed a recurrent phylogenetic and hierarchical grouping pattern. demonstrated a relatively large and highly variable accessory genome (comprising of 6284 genes with around 50% of them identified as singletons) that only partially correlated to the isolation source. Downstream analysis of the genomes resulted in the detection of 115 putative antimicrobial- and heavy-metal-resistance genes and 136 potential virulence factors that are associated with the induction of infection in host (e.g., , , ), survival and environmental adaptation (e.g., flagellar genes, CheA-CheY chemotaxis system, urease cluster). This study provides additional knowledge for a better -related risk assessment and highlights the need for further genomic epidemiology studies in Lithuania and other countries.
PubMed: 37374927
DOI: 10.3390/microorganisms11061425 -
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 -
Transcriptome Analysis of Arcobacter butzleri Infection in a Mucus-Producing Human Intestinal Model.Microbiology Spectrum Feb 2023Arcobacter butzleri is a foodborne pathogen belonging to the family. This Gram-negative bacterium is found in water, food, and various organisms, including farm...
Arcobacter butzleri is a foodborne pathogen belonging to the family. This Gram-negative bacterium is found in water, food, and various organisms, including farm animals, clams, and fish. Moreover, A. butzleri has been isolated from human stool samples, where it was associated with gastrointestinal symptoms such as diarrhea. The present study focused on the transcriptome analysis of three A. butzleri strains isolated from human stools and displaying variable virulence potential . We used a mucus-producing human intestinal model (Caco-2/HT29-MTX-E12) to study the colonization and invasion abilities of the three A. butzleri strains. The ability of all three A. butzleri strains to colonize our model system was subsequently confirmed. Moreover, transcriptomics showed the upregulation of putative virulence genes. Among these genes, , , and , which belong to the same operon, were upregulated in strain LMG 11119, which also had the greatest colonization ability. Moreover, genes not currently considered A. butzleri virulence genes were differentially expressed during cell model colonization. The main functions of these genes were linked to organic acid metabolism and iron transport and particularly to the function of the TonB complex. Recent advancements in the genomic characterization of A. butzleri revealed putative virulence genes and highlighted the possible pathogenic mechanisms used by this foodborne pathogen. It is therefore possible to study the transcriptomes of these bacteria to explore possible virulence mechanisms under conditions that mimic the infection process. The transcriptome and colonization/invasion analyses that we performed in this study enabled the evaluation of A. butzleri-mediated infection of the mucus-producing human intestinal model. We confirmed the upregulation of previously proposed virulence genes in the A. butzleri strains. In addition, we identified the differential expression of a number of other genes, which are not currently thought to be associated with virulence, in three A. butzleri strains during infection of mucus-producing human epithelial cells. Changes in the concentration of acetic acid and the upregulation of genes associated with organic acid metabolism during host-pathogen contact were also observed. These findings highlight the importance of previously unreported genes in the virulence mechanisms of A. butzleri.
Topics: Animals; Humans; Arcobacter; Caco-2 Cells; Virulence; Virulence Factors; Gene Expression Profiling
PubMed: 36622176
DOI: 10.1128/spectrum.02071-22 -
Antibiotics (Basel, Switzerland) Aug 2023The genus comprises a group of bacteria widely distributed in different habitats that can be spread throughout the food chain. Fluoroquinolones and aminoglycosides...
The genus comprises a group of bacteria widely distributed in different habitats that can be spread throughout the food chain. Fluoroquinolones and aminoglycosides represent the most common antimicrobial agents used for the treatment of infections. However, the increasing trend of the antimicrobial resistance of this pathogen leads to treatment failures. Moreover, the test implementation and interpretation are hindered by the lack of reference protocols and standard interpretive criteria. The purpose of our study was to assess the antibiotic resistance pattern of 17 strains isolated in Central Italy from fresh vegetables, sushi, chicken breast, and clinical human samples to provide new and updated information about the antimicrobial resistance epidemiology of this species. Antimicrobial susceptibility testing was carried out by the European Committee on Antimicrobial Susceptibility Testing (EUCAST)'s disc diffusion method. All the strains were multidrug resistant, with 100% resistance to tetracyclines and cefotaxime (third generation cephalosporins). Some differences were noticed among the strains, according to the isolation source (clinical isolates, food of animal origin, or fresh vegetables), with a higher sensitivity to streptomycin detected only in the strains isolated from fresh vegetables. Our data, together with other epidemiological information at the national or European Union (EU) level, may contribute to developing homogeneous breakpoints. However, the high prevalence of resistance to a wide range of antimicrobial classes makes this microorganism a threat to human health and suggests that its monitoring should be considered by authorities designated for food safety.
PubMed: 37627712
DOI: 10.3390/antibiotics12081292 -
FEBS Open Bio Oct 2020Arcobacter (A.) butzleri is an emerging zoonotic pathogen associated with gastrointestinal diseases, such as abdominal cramps and diarrhea, and is widely detected in...
Arcobacter (A.) butzleri is an emerging zoonotic pathogen associated with gastrointestinal diseases, such as abdominal cramps and diarrhea, and is widely detected in animals, showing a high prevalence in poultry and seafood. The survival and adaptation of A. butzleri to cold temperatures remains poorly studied, although it might be of interest for food safety considerations. To address this, growth patterns of eight A. butzleri isolates were determined at 8 °C for 28 days. A. butzleri isolates showed strain-dependent behavior: six isolates were unculturable after day 18, one exhibited declining but detectable cell counts until day 28 and one grew to the stationary phase level. Out of 13 A. butzleri cold shock-related genes homologous to Escherichia coli, 10 were up-regulated in response to a temperature downshift to 8 °C, as demonstrated by reverse transcription-quantitative PCR. Additionally, we compared these data with the cold-shock response in E. coli. Overall, we provide a deeper insight into the environmental adaptation capacities of A. butzleri, which we find shares similarities with the E. coli cold-shock response.
Topics: Arcobacter; Cold-Shock Response; Gene Expression; Gene Expression Profiling; Gene Expression Regulation; Temperature; Transcriptome
PubMed: 32810909
DOI: 10.1002/2211-5463.12959 -
Archives of Microbiology Nov 2023The surge in human arcobacteriosis has increased interest in determining the mechanisms involved in the pathogenesis of Arcobacter butzleri. Here, genomic analyses and...
The surge in human arcobacteriosis has increased interest in determining the mechanisms involved in the pathogenesis of Arcobacter butzleri. Here, genomic analyses and in vitro Caco-2 infection, motility, urease and antimicrobial susceptibility testing (AST) assays were used to characterise the virulence and antimicrobial resistance (AMR) determinants of strains HC-1, isolated from a patient with travellers' diarrhoea, and HC-2, isolated from another with pruritus. AMR determinants conferring resistance to tetracycline (tetO, present in both genomes) and to ampicillin and amoxicillin-clavulanic acid (bla3, present in HC-2) were identified. The same determinants associated with flagellum, chemotaxis, adhesion and invasion were detected in both, but HC-1 lacked eight flagellar genes. The urease cluster was only present in HC-1. Motility and urease tests confirmed the genetic differences between strains, but no genetic marker related to the inability of HC-2 to adhere and invade was identified. This inability could be conditioning the patient's pathology.
Topics: Humans; Virulence; Arcobacter; Caco-2 Cells; Urease; Genotype; Phenotype; Anti-Bacterial Agents
PubMed: 37923944
DOI: 10.1007/s00203-023-03709-3 -
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 Food Protection Jul 2021Campylobacter spp. and Arcobacter butzleri are foodborne pathogens associated with the consumption of contaminated raw chicken meat. At the industry level, the...
ABSTRACT
Campylobacter spp. and Arcobacter butzleri are foodborne pathogens associated with the consumption of contaminated raw chicken meat. At the industry level, the combination of new and common antimicrobials could be used as a strategy to control the presence of pathogens in chicken carcasses. The objective of this study was to determine the bacteriostatic and bactericidal effects of a mixture of chlorine (Cl) and sodium gallate (SG) on a mixture of two Campylobacter species (Campylobacter jejuni and Campylobacter coli) and A. butzleri. Using a central composite experimental design, it was established that the optimum inhibitory SG-Cl concentration for Campylobacter spp. was 44 to 45 ppm. After 15 h of incubation, Campylobacter species growth was reduced by 37.5% and the effect of Cl was potentiated by SG at concentrations above 45 ppm. In the case of A. butzleri, optimum levels of 28 and 41 ppm were observed for SG and Cl, respectively; no synergism was reported, as this bacterium was more sensitive to lower Cl concentrations than Campylobacter. After a 20-min pretreatment with peracetic acid (50 ppm), the optimum condition to achieve a >1.0-Log CFU/mL reduction of Campylobacter spp. was exposure to 177 ppm of Cl and 44 ppm of SG for 56 min. As A. butzleri showed lower resistance to the bacteriostatic effect of the Cl-SG combination, it was assumed that optimum bactericidal conditions for Campylobacter spp. were effective to control the former; this was confirmed with subsequent validation of the model. The SG-Cl combination has bactericidal properties against Campylobacter and A. butzleri, and it may be a useful strategy to improve sanitary practices applied in the poultry industry.
Topics: Animals; Arcobacter; Campylobacter; Chickens; Chlorine; Food Microbiology; Meat; Sodium
PubMed: 33428726
DOI: 10.4315/JFP-20-181 -
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