基质辅助激光解吸电离飞行时间质谱快速检测生菜中嗜麦芽窄食单胞菌

Rapid detection of Stenotrophomonas maltophilia in Lactuca sativa by matrix-assisted laser desorption ionization time of flight mass spectrometry

中文关键词:  MALDI-TOF-MS，生菜，嗜麦芽窄食单胞菌，特征指纹图谱

英文关键词:matrix-assisted laser desorption ionization time of flight mass spectrometry  Lactuca sativa  Stenotrophomonas maltophilia  characteristic fingerprint

中文摘要:

      目的 评价基质辅助激光解吸电离飞行时间质谱(matrix-assisted laser desorption ionization time of flight mass spectrometry, MALDI-TOF MS)在即食果蔬中微生物风险监测的应用价值, 确定生菜中的危害微生物及蛋白指纹图谱特征。方法 对成都地区50份生菜样品进行微生物的检测, 对分离的嗜麦芽窄食单胞菌进行生化鉴定和MALDI-TOF MS鉴定, 采用维恩分析(包括小于0.85‰偏差)对生菜中分离的嗜麦芽窄食单胞菌指纹图谱进行拟合, 采用系统聚类法对分离的嗜麦芽窄食单胞菌指纹图谱进行聚类分析。结果 50份生菜样品中检出11株嗜麦芽窄食单胞菌, MALDI-TOF MS获得其蛋白图谱拟合出特征性标识峰指纹图16组, 与数据库中超级谱图比对有9组不同标识峰, 为生菜分离菌特征峰; 蛋白指纹图谱聚类结果表明嗜麦芽窄食单胞指纹图谱有一定来源指向性, 但仍需更多数据修正。结论 嗜麦芽窄食单胞菌在生菜中检出率较高, 可作为危害风险特征微生物继续研究, MALDI-TOF MS可获得更多农产品中致病微生物特征信息, 作为农产品危害识别微生物快速鉴定及差异性分析应更深入的研究和扩大数据量, 并建立农产品微生物数据库系统。

英文摘要:

      Objective To evaluate the application value of matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF MS) in microbial risk monitoring of ready-to-eat fruits and vegetables, and to determine the characteristics of hazard identification microorganisms and protein fingerprints in Lactuca sativa. Methods The 50 samples of Lactuca sativa from Chengdu were tested and screened, and the isolated Stenotrophomonas maltophilia were identified by biochemical and MALDI-TOF MS. Wien analysis (including deviation less than 0.85‰) was used to fit the fingerprint of Stenotrophomonas maltophilia isolated from Lactuca sativa. The fingerprint of Stenotrophomonas maltophilia was analyzed by systematic clustering method. Results The 11 strains of Stenotrophomonas maltophilia were detected in 50 Lactuca sativa samples from Chengdu, and 16 groups of characteristic identification peaks were obtained by MALDI-TOF MS. Compared with the super spectrum in the database, the 9 groups of identification peaks were different from the characteristic peaks of Stenotrophomonas maltophilia isolated from Lactuca sativa. The clustering results of protein fingerprint showed that the fingerprint of Stenotrophomonas maltophilia had certain provenance orientation, but more data needed to be revised. Conclusion The high detection rate of Stenotrophomonas maltophilia in Lactuca sativa can be used as a hazard identification microorganism for further research, and MALDI-TOF MS can obtain more microbial characteristics information of agricultural products. As a rapid identification and difference analysis of agricultural product hazard identification microorganisms, more in-depth research and expanded data should be conducted to establish a microbial database system of agricultural products.