VFDB注释法在食源性金黄色葡萄球菌肠毒素基因分型分析中的应用  

Application of VFDB annotation method in genetic subtyping for enterotoxins in foodborne Staphylococcus aureus

作　　者：徐蕾蕊 汪琦 刘俊 巴哈提古丽·马那提拜 邓锐杰 曾静 孙震 XU Leirui;WANG Qi;LIU Jun;MANATIBAI·Guhatiguli;DENG Ruijie;ZENG Jing;SUN Zhen(China Customs Science and Technology Research Center,Beijing 100026,China;ChengduCustoms,Sichuan Chengdu 610041,China;Urumqi Customs,Xinjiang Urumqi 830018,China;Sichuan University,Sichuan Chengdu 610042,China)

机构地区：[1]中国海关科学技术研究中心,北京100026 [2]成都海关,四川成都610041 [3]乌鲁木齐海关,新疆乌鲁木齐830018 [4]四川大学,四川成都610042

出　　处：《中国食品卫生杂志》2022年第6期1218-1225,共8页Chinese Journal of Food Hygiene

基　　金：海关总署科研项目(2021HK214)。

摘　　要：目的 应用VFDB注释法对食源性金黄色葡萄球菌肠毒素基因进行分型并评价其准确性。方法 分别使用VFDB注释法和特异引物PCR方法对2009—2016年从北京地区食品中分离的53株金黄色葡萄球菌的18种肠毒素基因(包括传统肠毒素基因sea~see,新型肠毒素基因seg~sej和类肠毒素基因sek~seu)携带情况进行分析。将VFDB注释法所得肠毒素基因序列上传至NCBI,使用BLASTX程序和refseq_protein数据库对注释结果进一步核对。结果 VFDB注释法和PCR方法都检测出53株金黄色葡萄球菌分离株中有45株携带1种或多种肠毒素基因,有8株未携带肠毒素基因,肠毒素基因的总携带率为84.91%(45/53),经典肠毒素基因的携带率为58.49%(31/53)。45株携带肠毒素基因的分离株中,16株菌(35.56%,16/45)肠毒素基因VFDB分型结果与PCR一致,29株菌(64.44%,29/45)的肠毒素基因VFDB分型结果与PCR不一致。经BLASTX核对,VFDB注释法可能误判的基因型包括sea/sed、sea/sej、sea/sep、sea/ser、seg/ser和sek/sei(VFDB注释/BLASTX核对)。结论 VFDB注释法可对食源性金黄色葡萄球菌肠毒素基因进行分型分析,但是对注释为sea、seg和sek的序列建议采用BLASTX程序和refseq_protein数据库进一步核对,以提高基因分型的准确性。Objective To genetically subtype staphylococcal enterotoxins by applying VFDB annotation method and evaluate its accuracy.Methods VFDB annotation method and enterotoxin gene-specific PCR were applied to genetically subtype 18 staphylococcal enterotoxins(including traditional enterotoxin genes sea-see,new enterotoxin genes seg-sej and enterotoxin-like genes sek-seu) in 53 Staphylococcus aureus isolated from food in Beijing from 2009 to 2016.All the enterotoxin gene sequences obtained by VFDB annotation method were uploaded to NCBI platform and further verified by BLASTX program and refseq_protein database.Results Among the 53 Staphylococcus aureus isolates,45 isolates(84.91%,45/53) were identified to have one or more enterotoxin genes,and 8 isolates were without enterotoxin genes by both VFDB annotation method and gene-specific PCR.The traditional enterotoxin genes were found in 31 isolates(58.49%,31/53).Among the 45 isolates which carried enterotoxin genes,16 isolates(35.56%,16/45) had consistent enterotoxin gene typing results,and 29 isolates(64.44%,29/45) had inconsistent results between VFDB annotation methods and PCR method.Compared with BLASTX verified results,genotypes that could be misclassified by VFDB annotation method included sea/sed,sea/sej,sea/sep,sea/ser,seg/ser and sek/sei(VFDB annotation/BLASTX verification).Conclusion VFDB annotation could be applied as an optional method in predicting staphylococcal enterotoxin genes,but the sequence annotated as sea,seg and sek need to be further verified by BLASTX and refseq_protein database to improve the accuracy.

关 键 词：VFDB注释法 金黄色葡萄球菌 肠毒素 基因分型 

分 类 号：R155[医药卫生—营养与食品卫生学]