基质辅助激光解吸电离飞行时间质谱法对环境中芽孢杆菌的鉴定及溯源

Identification and traceability of Bacillus in the environment by matrix-assisted laser desorption lionization-time of flight mass spectrometry

目的 应用基质辅助激光解吸电离飞行时间质谱法(matrix-assisted laser desorption lionization-time of flight mass spectrometry, MALDI-TOF MS)对芽孢杆菌进行快速鉴定及聚类分析,研究MALDI-TOF MS对芽孢杆菌溯源的可行性。方法 实验菌株利用甲酸提取法提取蛋白,应用MALDI-TOF MS对22株环境分离菌株和枯草芽孢杆菌标准菌株CGMCC(B)1.1086进行鉴定。采集22株实验菌株的蛋白质指纹图谱,使用SARAMIS软件进行聚类分析。结果 枯草芽孢杆菌标准菌株CGMCC(B)1.1086的鉴定结果可信度为99.9%。22株环境菌均为芽孢杆菌,其中,6株菌鉴定到属水平,16株菌鉴定到种水平。在相似水平为80%的条件下,22株芽孢杆菌分为22个分支。结论 应用MALDI-TOF MS对芽孢杆菌进行快速鉴定与分型,对于芽孢杆菌溯源有重要意义,能够满足环境中芽孢杆菌检测及溯源的需求。

Objective To use the matrix-assisted laser desorption lionization-time of flight mass spectrometry(MALDI-TOF MS) to rapidly identify and cluster Bacillus, and study the feasibility of MALDI-TOF MS for traceability of Bacillus. Methods The experimental strains were extracted by formic acid extraction method, and 22environmental isolates and Bacillus subtilis standard strain CGMCC(B)1.1086 were identified by MALDI-TOF MS.The protein fingerprints of 22 experimental strains were collected, and the SARAMIS software was used for cluster analysis. Results The identification result of the standard strain of Bacillus subtilis CGMCC(B)1.1086 had a reliability of 99.9%. The 22 environmental bacteria identified were all Bacillus, of which 6 strains were identified to the genus level and 16 strains were identified to the species level. At a similar level of 80%, 22 strains of Bacillus were divided into 22 branches. Conclusion The rapid identification and typing of Bacillus by MALDI-TOF MS is of great significance for the traceability of Bacillus, and can meet the needs of detection and traceability of Bacillus in the environment.