Application of matrix-assisted laser desorption ionization-time of flight mass spectrometry for discrimination of laboratory-derived antibiotic-resistant bacteria

Abstract

The ability of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) to discriminate laboratory-derived antibiotic-resistant bacterial strains of known genetic origin was examined. A computer-based cluster analysis of spectral data successfully discriminated the majority of single- as well as multiple-antibiotic-resistant Escherichia coli strains examined. Cluster analysis of Staphylococcus aureus strains with different levels of novobiocin resistance showed that as the degree of resistance increased similarity to the wild-type strain decreased. These results demonstrate that MALDI-TOF MS is capable of discriminating antibiotic-resistant bacterial strains and may have potential for differentiating bacterial strains with varying degrees of antibiotic-resistance. © 2012 The Pharmaceutical Society of Japan.