title: Rapid identification of Mycoplasma pulmonis isolated from laboratory mice and rats using matrix-assisted laser desorption ionization time-of-flight mass spectrometry.
abstract: Mycoplasma species identification is based on biochemical, immunological, and molecular methods that require several days for accurate identification. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a novel method for identification of bacteria and has recently been introduced into the clinical microbiology laboratory as a rapid and accurate technique. This method allows a characteristic mass spectral fingerprint to be obtained from whole inactivated mycoplasmal cells. In this study, we evaluated the performance of the MALDI-TOF MS for the identification of Mycoplasma by comparison with standard sequence analysis of 16S rRNA. We developed the first database of MALDI-TOF MS profiles of Mycoplasma species, containing Mycoplasma pulmonis, M. arthritidis, and M. neurolyticum, which are the most common pathogens in mice and/or rats, and species-specific spectra were recorded. Using the database, 6 clinical isolates were identified. Six tracheal swabs from 4 mice and 2 rats were cultured on PPLO agar for 4 to 7 days, and the colonies were directly applied to analyze the protein profiles. Five strains were identified as M. pulmonis, and 1 strain from a mouse was identified as M. neurolyticum (spectral scores were >2.00); the results were consistent with the results of the 16S rRNA gene sequence analysis (homologies>97.0%). These data indicate that MALDI-TOF MS can be used as a clearly rapid, accurate, and cost-effective method for the identification of M. pulmonis isolates, and this system may represent a serious alternative for clinical laboratories to identify Mycoplasma species.
authors.affiliation: Department of Clinical Laboratory Medicine, School of Medical Technology, Teikyo University, 2-11-1 Kaga, Tokyo 173-8605, Japan. gotok@med.teikyo-u.ac.jp
authors.forename: Kazuo
authors.initials: K
authors.lastname: Goto
authors.forename: Mikachi
authors.initials: M
authors.lastname: Yamamoto
authors.forename: Miwa
authors.initials: M
authors.lastname: Asahara
authors.forename: Takashi
authors.initials: T
authors.lastname: Tamura
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Matsumura
authors.forename: Nobuhito
authors.initials: N
authors.lastname: Hayashimoto
authors.forename: Koichi
authors.initials: K
authors.lastname: Makimura
mesh_terms: D000818:Animals; D001483:Base Sequence; D051379:Mice; D009175:Mycoplasma Infections / Q000175:diagnosis / Q000382:microbiology / Q000662:veterinary*; D045803:Mycoplasma pulmonis / Q000302:isolation & purification*; D012329:RNA, Bacterial / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D051381:Rats; D012376:Rodent Diseases / Q000175:diagnosis / Q000382:microbiology*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000662:veterinary*
chemical_list: D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S