title: Genetic diversity of emetic toxin producing Bacillus cereus Korean strains.
abstract: Bacillus cereus is divided into emetic and enterotoxin producing strains. Emetic B. cereus showed the low level of genetic diversity and single evolutionary lineage but no specific study of the genotypic characterization of emetic B. cereus Korean strains has been conducted. The objective of this study was to investigate the genotypic diversity of emetic B. cereus Korean strains. A total 39 strains (35 clinical and 4 food isolates) was analyzed for the genotypic characterization. A total of 17 distinct patterns were obtained from the random-amplified polymorphic DNA (RAPD) banding patterns and the majority of clusters belong to group 3. The pulsed-field gel electrophoresis (PFGE) banding patterns were divided into 17 distinct pulsotypes, and groups B and C were dominated. Emetic B. cereus Korean strains showed diverse pulsotypes in contrast with previous studies. All strains were resistant to β-lactam antibiotics such as penicillin and ampicillin. Combining biochemical properties, PFGE types, RAPD types and antibiotic resistance types, a total of 7 composite clusters were found. The majority of composite clusters were consisted with cluster 5 and 6. Enterotoxin producing reference strains belong to composite cluster 7. However, JNHE 6 (Jeollabuk-do Research Institute of Health & Environment; cluster 1) and JNHE 36 (cluster 2) which possessed the ability of starch hydrolysis and saline fermentation showed different composite clusters comparing with most emetic B. cereus. JNHE 7 and JNHE 53 formed composite cluster 3 and 4. Emetic B. cereus Korean strains showed genotypic diversity comparing with the previous studies.
authors.affiliation: Division of Health Research & Planning, Gyeonggi-do Research Institute of Health & Environment, Pajang-dong, Suwon, Republic of Korea.
authors.forename: Jung-Beom
authors.initials: JB
authors.lastname: Kim
authors.forename: Jong-Suk
authors.initials: JS
authors.lastname: Park
authors.forename: Moon-Seok
authors.initials: MS
authors.lastname: Kim
authors.forename: Seong-Cheol
authors.initials: SC
authors.lastname: Hong
authors.forename: Joong-Hyun
authors.initials: JH
authors.lastname: Park
authors.forename: Deog-Hwan
authors.initials: DH
authors.lastname: Oh
mesh_terms: D001409:Bacillus cereus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001427:Bacterial Toxins / Q000235:genetics* / Q000378:metabolism; D047630:Depsipeptides / Q000235:genetics; D016521:Electrophoresis, Gel, Pulsed-Field; D004639:Emetics / Q000378:metabolism*; D004768:Enterotoxins / Q000032:analysis / Q000235:genetics*; D005516:Food Microbiology; D014644:Genetic Variation; D006801:Humans; D047090:beta-Lactams
chemical_list: D001427:Bacterial Toxins; D047630:Depsipeptides; D004639:Emetics; D004768:Enterotoxins; D047090:beta-Lactams