title: Toxin profile, antibiotic resistance, and phenotypic and molecular characterization of Bacillus cereus in Sunsik.
abstract: Sunsik, a ready-to-eat food in Korea, is comprised of various agricultural and marine products, and has been an important concern in Bacillus cereus food poisoning. The aim of this study was to investigate the toxin profiles, genotypic and phenotypic patterns as well as antibiotic resistance of B. cereus strains isolated from Sunsik. A subtyping method known as automated repetitive sequence-based PCR system (DiversiLab™) was used to assess the intraspecific biodiversity of these isolates. Thirty-five B. cereus strains were isolated from 100 commercial Sunsik samples, all of which harbored at least 1 enterotoxin gene. The detection rates of nheABC, hblCDA, cytK, and entFM enterotoxin gene among all isolates were 97%, 86%, 77%, and 100%, respectively. Most strains also produced corresponding enterotoxins such as HBL (83%) and NHE (94%). One strain (2.9%) carried the emetic toxin genes, including ces and EM1, and was positive for the HEp-2 cell emetic toxin assay. Most strains were positive for various biochemical tests such as salicin hydrolysis (86%), starch fermentation (89%), hemolysis (89%), motility test (100%) and lecithinase hydrolysis (89%). All isolates were susceptible to most antibiotics although they were highly resistant to β-lactam antibiotics. By using the automated rep-PCR system, all isolates were successfully differentiated, indicating the diversity of B. cereus strains present in Sunsik.
authors: KU Center for Food Safety, College of Veterinary Medicine, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul, Republic of Korea.
authors: Jung-Whan
authors: JW
authors: Chon
authors: Jong-Hyun
authors: JH
authors: Kim
authors: Sun-Jin
authors: SJ
authors: Lee
authors: Ji-Yeon
authors: JY
authors: Hyeon
authors: Kun-Ho
authors: KH
authors: Seo
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001409:Bacillus cereus / Q000187:drug effects* / Q000254:growth & development / Q000302:isolation & purification* / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001427:Bacterial Toxins / Q000378:metabolism* / Q000633:toxicity; D024881:Drug Resistance, Bacterial; D005506:Food Contamination / Q000032:analysis; D005516:Food Microbiology; D056945:Hep G2 Cells; D006801:Humans; D010641:Phenotype; D056910:Republic of Korea
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D001427:Bacterial Toxins