Rapid identification of Nontuberculous Mycobacterium using matrix assisted laser desorption/ionization time of flight mass spectrometry / 中华检验医学杂志

ABSTRACT

Objective The purpose of this study was to compare and develop the method for identification of Non-tuberculous Mycobacteria (NTM) using matrix assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS),and evaluate the feasibility,accuracy and repeatability of MALDI-TOF MS to discriminate NTM.Methods Fifteen clinical strains were collected from January to March in 2012 and 68 environmental strains were retrospectively collected from 2011 to 2012.A protocol for sample pre-treatment and protein extraction was developed and utilized it to identify clinical and environmental isolates.The results from 16 s rRNA sequencing were served as control.Results Method A was more effective in protein extraction.Although all the three methods got the same species result,a total of 83 strains belonging to 10 distinct species grown in Middle brook 7H10 media were analyzed.All members of the NTM were identified accurately at the genus level and 80.7％ (67/83) of strains could be identified at the species level.Six strains were identified at the complex level.81.9％ (68/83) of NTM got high spectral scores.The identification of cultured colony could be completed in 1.5 hours.And it had good reproducibility.Conclusion MALDI-TOF MS can be used as a rapid and accurate method for identification of Mycobacteria in clinical microbiology laboratories,implying its good application prospects.