title: MALDI-TOF Mass Spectrometry as a Useful Tool for Identification ofEnterococcusspp. from Wild Birds and Differentiation of Closely Related Species.
abstract: 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 withrpoAgene sequencing, and to evaluate the occurrence of bacteria of the genusEnterococcusin wild birds. In addition, a phyloproteomic analysis of certainEnterococcusspecies 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 (rpoAgene sequencing) methods were used to identify all the isolates. Using MALDI-TOF MS, all 54 (100%) isolates were identified asEnterococcusspp. 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 onrpoAsequences confirmed that all enterococci had been correctly identified.Enterococcus faecaliswas the most prevalent enterococcal species (50%) andEnterococcus faecium(33.3%) the second most frequent species, followed byEnterococcus hirae(9.3%),Enterococcus durans(3.7%), andEnterococcus casseliflavus(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 genusEnterococcus.
authors.affiliation: Department of Veterinary Prevention and Avian Diseases, Institute of Biological Bases of Animal Diseases, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, 20-612 Lublin, Poland.
authors.forename: Dagmara
authors.initials: D
authors.lastname: Stępień-Pyśniak
authors.affiliation: Department of Microbiology, Institute of Biology, University of Bialystok, 15-245 Bialystok, Poland.
authors.forename: Tomasz
authors.initials: T
authors.lastname: Hauschild
authors.affiliation: Department of Biology and Environmental Hygiene, Faculty of Biology and Animal Breeding, University of Life Sciences in Lublin, 20-950 Lublin, Poland.
authors.forename: Paweł
authors.initials: P
authors.lastname: Różański
authors.affiliation: Department of Veterinary Prevention and Avian Diseases, Institute of Biological Bases of Animal Diseases, Faculty of Veterinary Medicine, University of Life Sciences in Lublin, 20-612 Lublin, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Marek
mesh_terms: D000818:Animals; D000835:Animals, Wild / Q000382:microbiology; D001717:Birds / Q000382:microbiology*; D016983:Enterococcus / Q000145:classification / Q000302:isolation & purification*; D013293:Enterococcus faecalis / Q000235:genetics; D016984:Enterococcus faecium / Q000235:genetics; D006801:Humans; D010802:Phylogeny; D011044:Poland; D016133:Polymerase Chain Reaction / Q000379:methods; D040901:Proteomics; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
keywords: Enterococcus; MALDI-TOF MS; Wild birds; rpoA sequencing