title: Inhibition mechanism of Listeria monocytogenes by a bioprotective bacteria Lactococcus piscium CNCM I-4031.
abstract: Listeria monocytogenes is a pathogenic Gram positive bacterium and the etiologic agent of listeriosis, a severe food-borne disease. Lactococcus piscium CNCM I-4031 has the capacity to prevent the growth of L. monocytogenes in contaminated peeled and cooked shrimp. To investigate the inhibititory mechanism, a chemically defined medium (MSMA) based on shrimp composition and reproducing the inhibition observed in shrimp was developed. In co-culture at 26 °C, L. monocytogenes was reduced by 3-4 log CFU g(-1) after 24 h. We have demonstrated that the inhibition was not due to secretion of extracellular antimicrobial compounds as bacteriocins, organic acids and hydrogen peroxide. Global metabolomic fingerprints of these strains in pure culture were assessed by liquid chromatography coupled with high resolution mass spectrometry. Consumption of glucose, amino-acids, vitamins, nitrogen bases, iron and magnesium was measured and competition for some molecules could be hypothesized. However, after 24 h of co-culture, when inhibition of L. monocytogenes occurred, supplementation of the medium with these compounds did not restore its growth. The inhibition was observed in co-culture but not in diffusion chamber when species were separated by a filter membrane. Taken together, these data indicate that the inhibition mechanism of L. monocytogenes by L. piscium is cell-to-cell contact-dependent.
authors.affiliation: Laboratoire Ecosystèmes Microbiens et Molécules Marines pour les Biotechnologies (EM(3)B), Ifremer, Rue de l'Ile d'Yeu, 44311 Nantes Cedex 03, France; LUNAM Université, Oniris, UMR 1014 Secalim, Site de la Chantrerie, Nantes, F-44307, France; INRA, Nantes, F-44307, France.
authors.forename: Taous
authors.initials: T
authors.lastname: Saraoui
authors.affiliation: Laboratoire Ecosystèmes Microbiens et Molécules Marines pour les Biotechnologies (EM(3)B), Ifremer, Rue de l'Ile d'Yeu, 44311 Nantes Cedex 03, France; LUNAM Université, Oniris, UMR 1014 Secalim, Site de la Chantrerie, Nantes, F-44307, France; INRA, Nantes, F-44307, France.
authors.forename: Papa Abdoulaye
authors.initials: PA
authors.lastname: Fall
authors.affiliation: Laboratoire Ecosystèmes Microbiens et Molécules Marines pour les Biotechnologies (EM(3)B), Ifremer, Rue de l'Ile d'Yeu, 44311 Nantes Cedex 03, France.
authors.forename: Françoise
authors.initials: F
authors.lastname: Leroi
authors.affiliation: LUNAM Université, Oniris, USC INRA 1329, Laboratoire d'Etude des Résidus et Contaminants dans les Aliments (LABERCA), Nantes, F-44307, France.
authors.forename: Jean-Philippe
authors.initials: JP
authors.lastname: Antignac
authors.affiliation: LUNAM Université, Oniris, USC INRA 1329, Laboratoire d'Etude des Résidus et Contaminants dans les Aliments (LABERCA), Nantes, F-44307, France.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Chéreau
authors.affiliation: LUNAM Université, Oniris, UMR 1014 Secalim, Site de la Chantrerie, Nantes, F-44307, France; INRA, Nantes, F-44307, France. Electronic address: marie-france.pilet@oniris-nantes.fr.
authors.forename: Marie France
authors.initials: MF
authors.lastname: Pilet
mesh_terms: D000898:Antibiosis; D003470:Culture Media / Q000737:chemistry; D005516:Food Microbiology; D017045:Lactococcus / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D008089:Listeria monocytogenes / Q000254:growth & development* / Q000378:metabolism; D055432:Metabolomics; D012758:Shellfish / Q000382:microbiology
chemical_list: D003470:Culture Media
keywords: Bacterial interaction; Cellular contact; Chemically defined medium; Lactococcus piscium; Listeria monocytogenes; Nutrients competition