MALDI-TOF Mass Spectrometry as a Useful Tool for Identification of spp. from Wild Birds and Differentiation of Closely Related Species.

The aim of this study was to explore the accuracy and feasibility of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) in identifying bacteria from environmental sources, as compared with gene sequencing, and to evaluate the occurrence of bacteria of the genus in wild birds. In addition, a phyloproteomic analysis of certain species with spectral relationships was performed. The enterococci were isolated from 25 species of wild birds in central Europe (Poland). Proteomic (MALDI-TOF MS) and genomic ( gene sequencing) methods were used to identify all the isolates. Using MALDI-TOF MS, all 54 (100%) isolates were identified as spp. Among these, 51 (94.4%) isolates were identified to the species level (log(score) > or =2.0), and three isolates (5.6%) were identified at a level of probable genus identification (log(score) 1.88-1.927). Phylogenetic analysis based on sequences confirmed that all enterococci had been correctly identified. was the most prevalent enterococcal species (50%) and (33.3%) the second most frequent species, followed by (9.3%), (3.7%), and (3.7%). The phyloproteomic analysis of the spectral profiles of the isolates showed that MALDI-TOF MS is able to differentiate among similar species of the genus .