Dataset Information

Antibiotics resistance and toxin profiles of Bacillus cereus-group isolates from fresh vegetables from German retail markets.

ABSTRACT: BACKGROUND:This study aimed to evaluate the safety of raw vegetable products present on the German market regarding toxin-producing Bacillus cereus sensu lato (s.l.) group bacteria. RESULTS:A total of 147 B. cereus s.l. group strains isolated from cucumbers, carrots, herbs, salad leaves and ready-to-eat mixed salad leaves were analyzed. Their toxinogenic potential was assessed by multiplex PCR targeting the hemolysin BL (hbl) component D (hblD), non-hemolytic enterotoxin (nhe) component A (nheA), cytotoxin K-2 (cytK-2) and the cereulide (ces) toxin genes. In addition, a serological test was used to detect Hbl and Nhe toxins. On the basis of PCR and serological results, none of the strains were positive for the cereulide protein/genes, while 91.2, 83.0 and 37.4% were positive for the Hbl, Nhe and CytK toxins or their genes, respectively. Numerous strains produced multiple toxins. Generally, strains showed resistance against the ?-lactam antibiotics such as penicillin G and cefotaxim (100%), as well as amoxicillin/clavulanic acid combination and ampicillin (99.3%). Most strains were susceptible to ciprofloxacin (99.3%), chloramphenicol (98.6%), amikacin (98.0%), imipenem (93.9%), erythromycin (91.8%), gentamicin (88.4%), tetracycline (76.2%) and trimethoprim/sulfamethoxazole combination (52.4%). The genomes of eight selected strains were sequenced. The toxin gene profiles detected by PCR and serological test mostly agreed with those from whole-genome sequence data. CONCLUSIONS:Our study showed that B. cereus s.l. strains encoding toxin genes occur in products sold on the German market and that these may pose a health risk to the consumer if present at elevated levels. Furthermore, a small percentage of these strains harbor antibiotic resistance genes. The presence of these bacteria in fresh produce should, therefore, be monitored to guarantee their safety.

SUBMITTER: Fiedler G

PROVIDER: S-EPMC6842220 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Antibiotics resistance and toxin profiles of Bacillus cereus-group isolates from fresh vegetables from German retail markets.

Fiedler Gregor G Schneider Carmen C Igbinosa Etinosa O EO Kabisch Jan J Brinks Erik E Becker Biserka B Stoll Dominic A DA Cho Gyu-Sung GS Huch Melanie M Franz Charles M A P CMAP

BMC microbiology 20191109 1

<h4>Background</h4>This study aimed to evaluate the safety of raw vegetable products present on the German market regarding toxin-producing Bacillus cereus sensu lato (s.l.) group bacteria.<h4>Results</h4>A total of 147 B. cereus s.l. group strains isolated from cucumbers, carrots, herbs, salad leaves and ready-to-eat mixed salad leaves were analyzed. Their toxinogenic potential was assessed by multiplex PCR targeting the hemolysin BL (hbl) component D (hblD), non-hemolytic enterotoxin (nhe) com ...[more]

PMID: 31706266

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Dataset Information

Antibiotics resistance and toxin profiles of Bacillus cereus-group isolates from fresh vegetables from German retail markets.

Publications

Antibiotics resistance and toxin profiles of Bacillus cereus-group isolates from fresh vegetables from German retail markets.

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