A set of 204 taxonomically well-defined strains belonging to 17 Acinetobacter spp., including 11 recently described species (A. albensis, A. bohemicus, A. colistiniresistens, A. courvalinii. A. dispersus, A. gandensis, A. modestus, A. proteolyticus, A. seifertii, A. variabilis, and A. vivianii) and six species of the so-called haemolytic clade (A. beijerinckii, A. gyllenbergii, A. haemolyticus, A. junii, A. parvus, and A. venetianus), were subjected to MALDI-TOF mass spectrometric profiling. The identification outputs were evaluated using the current version (8.0.0.0) of the commercially available Bruker Daltonics, Biotyper database, which does not contain reference entries for six of the species tested. Up to 29% of the strains were falsely identified as different Acinetobacter spp. present in the Biotyper database, resulting mostly from the close phylogenetic relationship of species of the haemolytic clade. To obtain more reliable identification, extending the commercial database showed only partial improvement, while the use of an alternative MALDI matrix solution (strongly acidified ferulic acid) allowed correct identification of nearly all problematic strains.

Central European Institute of Technology Masaryk University Kamenice 5 62500 Brno Czech Republic

Central European Institute of Technology Masaryk University Kamenice 5 62500 Brno Czech Republic; National Centre for Biomolecular Research Faculty of Science Masaryk University Kamenice 5 625 00 Brno Czech Republic

Laboratory of Bacterial Genetics National Institute of Public Health Šrobárova 48 10042 Prague Czech Republic

Laboratory of Bacterial Genetics National Institute of Public Health Šrobárova 48 10042 Prague Czech Republic; Department of Laboratory Medicine 3rd Faculty of Medicine Charles University Prague Czech Republic

Citace poskytuje Crossref.org

Differentiation of Taxonomically Closely Related Species of the Genus Acinetobacter Using Raman Spectroscopy and Chemometrics