Studies on the distribution and antibiotic resistance of Arcobacter

Funder

Organizational Unit

Publications

Current insights on Arcobacter butzleri in food chain

Publication . Ferreira, Susana; Oleastro, Mónica; Domingues, F.C.

Arcobacter butzleri is an emerging pathogen with a global distribution, frequently found in the food chain. Its wide spread and association with human illness may point this bacterium as a possible causative agent of foodborne diseases usually associated with unknown etiology. Thus, the true pathogenic potential of A. butzleri and the associated risk of disease development must be clarified. Since its dispersion throughout the food chain is clear, this points toward a potential public health problem due to contaminated food and water, which is strengthened by the ability of this microorganism to survive in food products and water and by its resistance to stress created during food storage and processing.

2019Journal article

Restricted access

Arcobacter spp. at retail food from Portugal: Prevalence, genotyping and antibiotics resistance

Publication . Martins, Sofia Vicente; Oleastro, Mónica; Domingues, F.C.; Ferreira, Susana

Arcobacter genus is considered a foodborne emergent pathogen able to cause disease among humans and animals. The wide distribution and high prevalence of Arcobacter in food is becoming a concern, since consumption of contaminated food and water is considered the most probable route of Arcobacter transmission to humans. In this work, ready-to-eat packaged vegetables, poultry, pork, beef and fish meat were purchased from several retail markets and supermarkets and tested for the presence of Arcobacter spp. Suspected colonies were isolated and identified, characterized through ERIC-PCR and resistance to nine antibiotics commonly used to treat infections by this microorganism was assessed; in parallel, Arcobacter spp. was directly detected on enrichment broth by multiplex PCR. The results show a high prevalence of Arcobacter spp. among retail food, with an overall prevalence of 60.5% obtained by both molecular and culture detection. A. butzleri was the most frequently isolated species (58.5%) followed by A. cryaerophilus (35.8%) and A. skirrowii (5.7%). A high genetic diversity among the isolates was observed, despite the detection of a possible cross-contamination between food samples. Also, a high rate of multidrug resistance among the isolates (85.7%) was observed. Taken together, our results suggest that the consumption of Arcobacter-contaminated food products is of public health concern.

2018Journal article

Restricted access

Arcobacter butzleri Ciprofloxacin Resistance: Point Mutations in DNA Gyrase A and Role on Fitness Cost

Publication . Ferreira, Susana; Correia, Daniela R.; Oleastro, Mónica; Domingues, F.C.

Arcobacter butzleri is a widely distributed emerging pathogen resistant to various classes of antimicrobial agents, namely fluoroquinolones. A. butzleri resistance to fluoroquinolones is conferred by point mutations at the antibiotic target. The aim of this study was to evaluate mutations at gyrA associated with ciprofloxacin resistance and evaluate whether acquisition of resistance impacts on fitness and stress tolerance of A. butzleri. A. butzleri ciprofloxacin mutants were generated by laboratory induction. Identification of mutations associated with ciprofloxacin resistance was performed by gyrA sequencing. Growth kinetics, cost of fitness, biofilm formation ability, and stress tolerance were assessed. Two amino acid substitutions in the quinolone resistance-determining region of GyrA were identified in the mutant strains, one previously described (Thr-85-Ile) and a new substitution (Asp-89-Tyr). No differences in growth kinetics were recorded between parental and mutant strains; however, fitness cost was variable, according to the genetic background of the strains, and independently of ciprofloxacin resistance. Overall, the ciprofloxacin resistance development did not significantly affect stress tolerance, motility, or biofilm-forming ability. In conclusion, acquisition of ciprofloxacin resistance in A. butzleri is associated with mutations in gyrA and is likely well compensated, with cost of fitness reflecting the diversity in genetic background of this bacterium.

2018Journal article

Restricted access

Occurrence, genetic diversity and antibiotic resistance of Arcobacter sp. in a dairy plant

Publication . Ferreira, Susana; Oleastro, Mónica; Domingues, F.C.

Aims The aim of this study was to evaluate the occurrence, diversity and resistance to antibiotics of Arcobacter sp. in a dairy plant samples. Methods and Results A total of 75 samples from dairy plant surfaces and materials and several food products collected in different steps of the cheese production process were analysed by culture, under aerobic and microaerobic atmospheric conditions, and by enrichment molecular detection. Isolates were identified and genotyped by ERIC‐PCR, and their susceptibility to nine antibiotics was evaluated by agar dilution. Global prevalence of Arcobacter sp. was 42·7%, where 20 of the 42 food samples analysed were positive for A. butzleri by both culture and molecular detection, one for A. marinus by culture and one for A. cryaerophilus by molecular detection only; 10 of the 30 analysed materials and plant surfaces were positive for A. butzleri. All A. butzleri isolates were resistant to nalidixic acid and showed high resistance rates to ampicillin (56·2%) and cefotaxime (97·9%), being all strains susceptible to gentamicin and erythromycin. Conclusions Contamination of dairy plant environment with A. butzleri and its progression along cheese production process were observed, however, the cheese ripening process may have a relevant role in the reduction of the contamination. Significance and Impact of the Study This study showed the presence of Arcobacter sp. in a dairy plant, displaying its high prevalence and genetic diversity and highlighting its high resistance rates. The data obtained could contribute to further acknowledge the Arcobacter food contamination as a potential health hazard.

2017Journal article

Restricted access