Identification and classification of non-tuberculosis Mycobacterium by matrix-assisted laser desorption ionization-time of flight mass spectrometry / 中华检验医学杂志

ABSTRACT

Objective Reference standard of the RPOB(rifampin resistance)gene recommended by CLSI-MM18A(Interpretive Criteria for Identification of Bacteria and Fungi by DNA Target Sequencing) was used to evaluate the ability of MALDI-TOFMS techniques for the identification and classification of non-tuberculous Mycobacterium.Methods Fifty five clinicalstrains were collected from 2012 to 2016 with different sources.The RPOB gene was sequenced, and results were applied to phylogenetics analysis. MALDI-TOF MS technology was implemented to identify the strains, and cluster analysis was conducted based on protein fingerprint.The consistency of two methods for NTM identification and typing was evaluated.Results The RPOB gene method showed a good ability of identification(similarity>99.0%) and subtyping(to subspeciesof the complex level).The French BioMérieux MALDI-TOF MS identified 89.1% of 55 strains to genus level and 78.2% to species level.The phylogeneticsanalysis of protein fingerprint by SARAMS Premium software also showed good typing ability.Conclusions MALDI-TOF MS technology can identify and classify non-tuberculous Mycobacterium effectively,which is rapid and easy.It is complementary to RPOB gene method in laboratory application.