为了确定成都市食品中蜡样芽孢杆菌所携带的毒力基因情况，本实验对市售食品共采样130份，通过菌落在MYP培养基上形态特征对蜡样芽孢杆菌进行初步分离，再利用16S rRNA测序结果进行比对分析，并检测分离菌株携带的管家基因gyrB、rpoB、VrrA、groEL进一步确认，最后检测分离菌株携带毒力基因情况。结果表明130份样品中共检出23株蜡样芽孢杆菌，检出率为17.7%；23株分离菌株中，蜡样芽孢杆菌的4个管家基因gyrB、rpoB、VrrA、groEL检出率为100%，毒力基因的检测结果表明，nheB和entFM在16株分离菌株中检出，检出率为69.6%；nheA和nheC在14株分离菌株中检出，检出率为60.9%；hblD在11株分离菌株中检出，检出率为47.8%；cytK在10株分离菌株中检出，检出率为43.5%；bceT在9株分离菌株中检出，检出率为39.1%；hblA和hblC在8株分离菌株中检出，检出率为34.8%；cer和ces在2株分离菌株中检出，检出率为8.7%；未发现分离菌株携带hblB和Hly基因。研究结果表明市售食品中分离的蜡样芽孢杆菌毒力基因携带率较高，对食品安全具有潜在威胁，应当引起有关部门注意。

To identify the virulence genes of Bacillus cereus food isolates,a total of 130 food samples were collected in Chengdu city in this study. The isolation of Bacillus cereus strains was performed according to the colony morphology on MYP medium. Then 16S rRNA sequencing analysis and Bacillus cereus housekeeping genes (gyrB, rpoB, VrrA, groEL) were used to identify the isolates. Finally, the virulence genes of Bacillus cereus isolates were detected. The results showed that 23 Bacillus cereus isolates were identified from 130 collected food samples. The isolation rate was 17.7%. Twenty-three Bacillus cereus isolates carried all four housekeeping genes (gyrB, rpoB, VrrA, groEL). The virulence genes detection showed nheB and entFM were found in 16 isolates and the detection rates were relatively high (16/23, 69.6%); the nheA and nheC genes were detected in 14 isolated strains and the detection rates were 60.9%; the hblD gene was detected in 11 isolates and the detection rate was 47.8%; the cytK gene was detected in 10 isolates and the detection rate was 43.5%; the bceT gene was detected in 9 isolates and the detection rate was 39.1%; the hblA and hblC genes were detected in 8 strains and the detection rates were 34.8%; the cer and ces genes were detected in 2 isolated strains, and the detection rates were 8.7%; the hblB and Hly genes were not found in any isolates. This study indicated that the occurrence rates of virulence genesin Bacillus cereus food isolates were relatively high, which had a potential threat to food safety. The regulatory authority should pay attention to Bacillus cereus contamination.

国家重点研发计划（2018YFD0500500）；西南民族大学研究生创新课题（CX2018SZ18）