Abstract：Objective To evaluate the feasibility of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for homology analysis of Salmonella isolated from foodborne disease outbreaks, and to provide technical support for the treatment of Salmonella outbreaks. Methods We collected 42 strains of Salmonella associated with 5 foodborne disease outbreaks in Changsha City in recent years, and then performed biochemical identification, serotyping and PFGE typing. The mass spectrum data about the 42 Salmonella strains were collected by MALDI-TOF MS technology to construct the main spectrum (MSP), and then the MSP was identified by MBT Compass software. Correlation distance cluster homology analysis was performed on the 42 Salmonella strains, and then 4 times of cluster homology analyses without and with reference strains were conducted on the related Salmonella strains of different events. The results of MSP dendrogram were compared with those of PFGE cluster analysis. Results Five Salmonella strains were isolated from 29 food samples, and 37 Salmonella strains from 62 patient samples. The results of MSP and biochemical identification of the 42 Salmonella strains were completely consistent, and the strains were identified as 22 strains of Salmonella enteritidis, 17 strains of Salmonella braenderup and 3 strains of Salmonella typhimurium. The Salmonella strains from the 5 events were divided into four internal completely consistent branches by PFGE. MSP dendrogram of the 42 Salmonella strains was divided into three different branches at the level of 300 relative correlation distance, which was consistent with serotyping and roughly the same as PFGE cluster typing. Four times of mass spectrometry clustering homology analysis without reference strains could not cluster related strains from the expected cluster, but after adding reference strains, the strains in the same event were clustered into a cluster with close to 100% similarity, which was highly consistent with the PFGEtyping results. Conclusion MALDI-TOF MS clustering analysis by MSP dendrogram can be used to confirm the homology of Salmonellafoodborne disease outbreaks in a certain range, and can be used as a good complementary method to PFGE homology analysis, but it cannot directly compare different platform data.
苏良, 宋迎春, 杨柳青, 张玉娟, 刘晓蕾. MALDI-TOF MS用于沙门菌食源性疾病暴发同源性分析初步研究[J]. 实用预防医学, 2023, 30(4): 406-410.
SU Liang, SONG Ying-chun, YANG Liu-qing, ZHANG Yu-juan, LIU Xiao-lei. Preliminary study on homology analysis of Salmonella isolated from foodborne disease outbreaks by MALDI-TOF MS. , 2023, 30(4): 406-410.
2023, Vol. 30 
