On the basis of various guidelines for drinking-water quality, five species of
bacteria (Helicobacter pylori, Salmonella typhimurium, Yersinia enterocolitica,
Legionella pneumophila, and Campylobacter jejuni) were selected as representatives
of waterborne microbial pathogens. Matrix-associated laser-desorption/ionization timeof-
flight mass spectrometry (MALDI-TOF MS) analysis was conducted to identify the five
bacteria, and the MALDI-TOF MS results were compared with results obtained through
16S rRNA identification. The MALDI-TOF MS analysis yielded score values of 1.60 ± 0.19,
2.41 ± 0.09, 2.37 ± 0.16, 2.19 ± 0.15, and 1.85 ± 0.08 for H. pylori, S. typhimurium, Y.
enterocolitica, L. pneumophila, and C. jejuni, respectively. In addition, the MALDI-TOF
identification results were well-correlated with those from the 16S rRNA identification.
This study suggests that MALDI-TOF-based identification is an inexpensive, rapid,
reproducible, and accurate alternative method for the identification of waterborne
microbial pathogens in aquatic environments.