Discrimination of Species by Combining MALDI-TOF Protein Profile, Chaperonin Sequences, and Phenotypic Characteristics.

The description of was recently updated and three new species, including nine genome species within , were defined using whole genome sequences and matrix assisted laser desorption ionization time of flight (MALDI-TOF) mass spectrometry. A fast and simple method based on readily available techniques would be of immense use to identify species in research and clinical practice. Here we show that 34 previously characterized isolates were assigned to the species using partial chaperonin sequences. The MALDI Biotyper from Bruker Daltonik GmbH demonstrated the capability to differentiate the phylogenetically diverse groups composed of / and /. Among the phenotypic properties that characterize species are sialidase and β-galactosidase activities. Our data confirmed that the NanH3 enzyme is responsible for sialidase activity in spp. isolates. Almost all isolates displayed a sialidase positive phenotype, whereas the majority of strains were sialidase negative. and displayed a sialidase negative phenotype. β-galactosidase is produced exclusively in . strains. Earlier determined phenotypic characteristics associated with virulence of isolates now assigned to the defined species may provide insights on how diverse species contribute to shaping the vaginal microbiome.