title: Genotypic diversity of Lactobacillus sanfranciscensis strains isolated from French organic sourdoughs.
abstract: Lactobacillus sanfranciscensis is the predominant key lactic acid bacterium in traditionally fermented sourdoughs. Despite its prevalence, sourdough and their related breads could be different regarding their physicochemical and sensorial characteristics. The intraspecific diversity of L. sanfranciscensis might explain these observations. Fifty-nine strains isolated from French sourdoughs were typed by a polyphasic approach including Multilocus Sequence Typing (MLST) and Pulsed-field Gel Electrophoresis (PFGE), in order to study their genotypic diversity. MLST scheme can be reduced from six to four gene fragments (gdh, gyrA, nox and pta) without a major loss of discrimination between strains. The genes mapA and pgmA are not good candidates for inclusion in an MLST scheme to type L. sanfranciscensis strains, as they could not be amplified for a set of 18 strains among the 59 studied. This method revealed 20 sequence types (STs). Of these, 19 STs were grouped in one clonal complex, showing a strong relatedness between these strains. PFGE using SmaI discriminated 41 pulsotypes and so distinguished isolates better than the MLST scheme. Both genotypic methods indicate a low diversity between strains isolated from the same sourdough and a higher diversity between strains isolated from different sourdoughs, suggesting an influence of baker practices and/or environmental conditions on the selection of strains. The use of these two methods targeting genetic variations gives an optimal genotypic characterization of L.sanfranciscensis strains.
authors.affiliation: Oniris, Laboratoire de Microbiologie Alimentaire et Industrielle, rue de la Géraudière, Nantes Cedex 3, France.
authors.forename: Emilie
authors.initials: E
authors.lastname: Lhomme
authors.affiliation: Oniris, Laboratoire de Microbiologie Alimentaire et Industrielle, rue de la Géraudière, Nantes Cedex 3, France.
authors.forename: Bernard
authors.initials: B
authors.lastname: Onno
authors.affiliation: INRA, UMR 1253 Science et Technologie du Lait et de l'Oeuf, CIRM-BIA, 65 Rue de St Brieuc, 35042 Rennes, France.
authors.forename: Victoria
authors.initials: V
authors.lastname: Chuat
authors.affiliation: INRA, UMR 1345 Institut de Recherches en Horticulture et Semence, SFR4207 Quasav, Beaucouzé, France.
authors.forename: Karine
authors.initials: K
authors.lastname: Durand
authors.affiliation: Oniris, Laboratoire de Microbiologie Alimentaire et Industrielle, rue de la Géraudière, Nantes Cedex 3, France.
authors.forename: Servane
authors.initials: S
authors.lastname: Orain
authors.affiliation: INRA, UMR 1253 Science et Technologie du Lait et de l'Oeuf, CIRM-BIA, 65 Rue de St Brieuc, 35042 Rennes, France.
authors.forename: Florence
authors.initials: F
authors.lastname: Valence
authors.affiliation: INRA, UMR 1014 Secalim, Rue de la Géraudière, Nantes Cedex 3, France. Electronic address: xavier.dousset@oniris-nantes.fr.
authors.forename: Xavier
authors.initials: X
authors.lastname: Dousset
authors.affiliation: INRA, UMR 1345 Institut de Recherches en Horticulture et Semence, SFR4207 Quasav, Beaucouzé, France. Electronic address: marie-agnes.jacques@angers.inra.fr.
authors.forename: Marie-Agnès
authors.initials: MA
authors.lastname: Jacques
mesh_terms: D001939:Bread / Q000382:microbiology*; D016521:Electrophoresis, Gel, Pulsed-Field; D005285:Fermentation; D005516:Food Microbiology; D014644:Genetic Variation; D005838:Genotype; D007778:Lactobacillus / Q000235:genetics*; D058885:Multilocus Sequence Typing
keywords: Lactobacillus sanfranciscensis; Multilocus sequence typing; Pulsed-field gel electrophoresis; Sourdough