title: Cell-to-cell contact and antimicrobial peptides play a combined role in the death of Lachanchea thermotolerans during mixed-culture alcoholic fermentation with Saccharomyces cerevisiae.
abstract: The roles of cell-to-cell contact and antimicrobial peptides in the early death of Lachanchea thermotolerans CBS2803 during anaerobic, mixed-culture fermentations with Saccharomyces cerevisiae S101 were investigated using a commercially available, double-compartment fermentation system separated by cellulose membranes with different pore sizes, i.e. 1000 kDa for mixed- and single-culture fermentations, and 1000 and 3.5-5 kDa for compartmentalized-culture fermentations. SDS-PAGE and gel filtration chromatography were used to determine an antimicrobial peptidic fraction in the fermentations. Our results showed comparable amounts of the antimicrobial peptidic fraction in the inner compartments of the mixed-culture and 1000 kDa compartmentalized-culture fermentations containing L. thermotolerans after 4 days of fermentation, but a lower death rate of L. thermotolerans in the 1000 kDa compartmentalized-culture fermentation than in the mixed-culture fermentation. Furthermore, L. thermotolerans died off even more slowly in the 3.5-5 kDa than in the 1000 kDa compartmentalized-culture fermentation, which coincided with the presence of less of the antimicrobial peptidic fraction in the inner compartment of that fermentation than of the 1000 kDa compartmentalized-culture fermentation. Taken together, these results indicate that the death of L. thermotolerans in mixed cultures with S. cerevisiae is caused by a combination of cell-to-cell contact and antimicrobial peptides.
authors.affiliation: Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 26, 1958 Frederiksberg C, Denmark.
authors.forename: Varongsiri
authors.initials: V
authors.lastname: Kemsawasd
authors.affiliation: Unit of Bioenergy, Laboratório Nacional de Energia e Geologia (LNEG), Estrada do Paço do Lumiar 22, 1649-038, Portugal.
authors.forename: Patrícia
authors.initials: P
authors.lastname: Branco
authors.affiliation: Centro de investigação interdisciplinar Egas Moniz, Instituto Superior de Saúde Egas Moniz, Campus Universitário, Quinta da Granja, 2829-511 Monte de Caparica, Portugal UCIBIO REQUIMTE - Dept. Química, Faculdade de Ciências e Tecnologia (UNL), 2829-516 Monte Caparica, Portugal.
authors.forename: Maria Gabriela
authors.initials: MG
authors.lastname: Almeida
authors.affiliation: Centro de investigação interdisciplinar Egas Moniz, Instituto Superior de Saúde Egas Moniz, Campus Universitário, Quinta da Granja, 2829-511 Monte de Caparica, Portugal UCIBIO REQUIMTE - Dept. Química, Faculdade de Ciências e Tecnologia (UNL), 2829-516 Monte Caparica, Portugal.
authors.forename: Jorge
authors.initials: J
authors.lastname: Caldeira
authors.affiliation: Unit of Bioenergy, Laboratório Nacional de Energia e Geologia (LNEG), Estrada do Paço do Lumiar 22, 1649-038, Portugal.
authors.forename: Helena
authors.initials: H
authors.lastname: Albergaria
authors.affiliation: Department of Food Science, Faculty of Science, University of Copenhagen, Rolighedsvej 26, 1958 Frederiksberg C, Denmark na@food.ku.dk.
authors.forename: Nils
authors.initials: N
authors.lastname: Arneborg
mesh_terms: D000935:Antifungal Agents / Q000378:metabolism*; D015169:Colony Count, Microbial; D004591:Electrophoresis, Polyacrylamide Gel; D000431:Ethanol / Q000378:metabolism; D005285:Fermentation; D007218:Industrial Microbiology; D010455:Peptides / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000254:growth & development / Q000502:physiology*; D004718:Saccharomycetales / Q000502:physiology*; D014920:Wine / Q000382:microbiology*
chemical_list: D000935:Antifungal Agents; D010455:Peptides; D000431:Ethanol
keywords: antimicrobial peptides; cell-to-cell contact; early death; mixed-culture fermentation