克罗诺杆菌MALDI-TOF-MS数据库的建立及应用

Establishment and Application of an Analytical Database for Cronobacter spp. by Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry

应用基质辅助激光解吸电离飞行时间质谱(matrix-assisted laser desorption ionisation time-of-flight mass spectrometry,MALDI-TOF-MS)技术建立了克罗诺杆菌MALDI-TOF-MS数据库,用于该菌属内种和亚种的高通量鉴定及菌株分型。在优化培养条件、样品处理方法及确定MALDI-TOF-MS蛋白质指纹图谱采集参数的基础上,将采集的8种参考菌株蛋白质质谱数据通过Biotyper软件构建克罗诺杆菌的MALDI-TOF-MS数据库,再用相近肠杆菌及该属分离株验证数据库的准确性。结果表明:应用建立的克罗诺杆菌的MALDI-TOF-MS数据库对135株克罗诺杆菌分离株进行分析,鉴定分值均不小于2.0,达到了种水平鉴定要求,通过聚类分析,可进一步分型。构建的MALDI-TOF-MS数据库为克罗诺杆菌高通量鉴定与分型提供了一种新的手段。

The purpose of this study was to establish an analytical database for high throughput identification and subtyping of 8 species of Cronobacter spp.by a matrix-assisted laser desorption ionization time-of-flight mass spectrometry （MALDI-TOF-MS） method.Under the optimized culture and sample treatment conditions by using the established MALDI-TOF-MS protein fingerprint acquisition parameters,the acquired characteristic protein mass spectrometric profiles of 8 reference strains were used to build a MALDI-TOF-MS database with Biotyper software,and the accuracy of the database was validated by comparison with data from related enterobacteriaceae strains and isolates of the genus Cronobacter.The MALDI-TOF-MS database was applied to analyze 135 isolates of Cronobacter spp.with an identification score no smaller than 2.0,which reached the requirement for identification at the species level.Further subtyping was achieved by cluster analysis.This MALDI-TOF-MS database may provide a new approach for high throughput identification and subtyping of Cronobacter strains.