title: MALDI-TOF mass spectrometry for the identification of lactic acid bacteria isolated from a French cheese: The Maroilles.
abstract: In this study we identified the culturable population of mesophilic lactic acid bacteria (LAB) from a French cheese Maroilles made either with raw or pasteurized milk using MALDI-TOF mass spectrometry (MS). Samples from rind and heart of Maroilles cheese were used, the LAB were selected on MRS agar at 30°C and 197 Gram-positive and catalase-negative strains were subjected to identification by MALDI-TOF MS profiling. All strains were unambiguously identified: 105 strains from Maroilles made with raw milk (38 on the rind and 67 in the heart) and 92 strains from Maroilles made with pasteurized milk (39 on the rind and 53 in the heart). MALDI-TOF MS identification allowed identification of three genera belonging to LAB including Lactobacillus, Enterococcus and Leuconostoc. Lactobacillus was the most represented genus with seven species: Lactobacillus plantarum (L. plantarum), L. paracasei, L. curvatus, L. rhamnosus, L. fructivorans, L. parabuchneri, L. brevis found in Maroilles made with both kind of milk. The correlation between the 16S rDNA-based identification performed on selected strains and those obtained by MALDI-TOF-MS demonstrates that this fast, economically affordable, robust and reliable method for bacteria characterisation stands as an attractive alternative to the commonly-used methods and its application in food industry is discussed.
authors.affiliation: Institut Charles VIOLLETTE (ICV) EA 7394, ISA, F-59000 Lille, France; Univ Lille, F-59000 Lille, France.
authors.forename: Menouar
authors.initials: M
authors.lastname: Nacef
authors.affiliation: Univ Lille, F-59000 Lille, France.
authors.forename: Mickaël
authors.initials: M
authors.lastname: Chevalier
authors.affiliation: Institut Charles VIOLLETTE (ICV) EA 7394, ISA, F-59000 Lille, France.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Chollet
authors.affiliation: Univ Lille, F-59000 Lille, France.
authors.forename: Djamel
authors.initials: D
authors.lastname: Drider
authors.affiliation: Univ Artois, F-62307 Lens, France. Electronic address: christophe.flahaut@univ-artois.fr.
authors.forename: Christophe
authors.initials: C
authors.lastname: Flahaut
mesh_terms: D000818:Animals; D015373:Bacterial Typing Techniques / Q000379:methods*; D002417:Cattle; D002611:Cheese / Q000382:microbiology*; D019344:Lactic Acid / Q000378:metabolism; D056546:Lactobacillales / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D008892:Milk / Q000382:microbiology; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
chemical_list: D019344:Lactic Acid
keywords: Bacteria identification; Cow-milk cheese; Lactic acid bacteria; MALDI-TOF MS; Mass spectrometry