Comparison of enterotoxin production and phenotypic characteristics between emetic and enterotoxic Bacillus cereus.
Bacillus cereus was divided into emetic toxin (cereulide)- and enterotoxin-producing strains, but emetic toxin-producing B. cereus is difficult to detect immunochemically. Screening methods for emetic toxin-producing B. cereus are needed. The objectives of this study were to identify and detect emetic toxin-producing B. cereus among 160 B. cereus strains, and to compare enterotoxin production and phenotypic characteristics between the emetic toxin-producing and enterotoxin-producing strains. Forty emetic toxin-producing B. cereus strains were determined with high-pressure liquid chromatography-mass spectrometry analysis. Among the emetic toxin-producing strains (n = 40), 31 (77.5%) and 3 (7.5%) strains produced nonhemolytic enterotoxin (NHE) and hemolysin BL (HBL) enterotoxins, respectively. In addition, 107 (89.2%) and 100 (83.3%) strains produced NHE and HBL enterotoxins among the enterotoxin-producing strains (n = 120). The number of strains positive for starch hydrolysis, salicin fermentation, and hemolysis among the emetic toxin-producing strains were 3 (7.5%), 3 (7.5%), and 26 (65.0%), respectively, and among enterotoxin-producing strains, these numbers were 101 (84.2%), 100 (83.3%), and 111 (92.5%), respectively. In particular, the three emetic toxin-producing B. cereus strains (JNHE 6, JNHE 36, and KNIH 28) produced the HBL and NHE enterotoxins and were capable of starch hydrolysis and salicin fermentation. The absence of HBL enterotoxin and certain phenotypic properties, such as starch hydrolysis and salicin fermentation, indicates that these properties were not critical characteristics of the emetic toxin-producing B. cereus tested in this study.
Kim
Jung-Beom
JB
Division of Health Research and Planning, Gyeonggi-do Research Institute of Health and Environment, Gyeonggi-do, Republic of Korea.
Kim
Jai-Moung
JM
Kim
So-Yeong
SY
Kim
Jong-Hyun
JH
Park
Yong-Bae
YB
Choi
Na-Jung
NJ
Oh
Deog-Hwan
DH
D001409:Bacillus cereus / Q000145:classification / Q000302:isolation & purification* / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D015169:Colony Count, Microbial; D047630:Depsipeptides / Q000032:analysis* / Q000096:biosynthesis; D004768:Enterotoxins / Q000032:analysis* / Q000096:biosynthesis; D005506:Food Contamination / Q000032:analysis*; D005516:Food Microbiology; D006801:Humans; D013058:Mass Spectrometry; D010641:Phenotype; D013045:Species Specificity
D047630:Depsipeptides; D004768:Enterotoxins; C089294:cereulide; C040792:enterotoxin, Bacillus cereus