Screening specific genes and virulence genes of Bacillus cereus for its rapid identification and detection

ObjectiveTo screen the specific genes and virulence genes of Bacillus cereus for its rapid identification and detection.

MethodsA total of 329 B. cereus strains isolated from food and soil were used to evaluate the specificity of gyrB and groEL genes for the identification of B. cereus and investigate the distribution of virulence genes with PCR method. The appropriate genes were selected to develop a multiplex PCR assay for rapid detection of B. cereus.

ResultsAmong the studied B. cereus and closely related Bacillus strains, gyrB gene was specific for B. cereus except for one B. thuringiensis strain, however, groEL gene was amplified in four species. The carrying rates of six virulence genes of nheA, entFM, bceT, hblC, cytK and ces were 84.19%, 79.64%, 49.24%, 47.72%, 47.11% and 1.52%, respectively. Six genes, gyrB, hblC, nheA, entFM, ces and cytK, were selected. Two multiplex PCR systems, including one duplex PCR (gyrB and cytK) and one quadruple PCR (nheA, hblC, entFM and ces), were optimized.

ConclusionThe specific genes and virulence genes of B. cereus screened can be used in the detection of B. cereus in a comprehensive, specific, simple and effective way and have good potential in laboratory detection practice.