title: Effects of the strain background and autolysis process on the composition and biophysical properties of the cell wall from two different industrial yeasts.
abstract: The Saccharomyces cerevisiae cell surface is endowed with some relevant technological properties, notably antimicrobial and biosorption activities. For these purposes, yeasts are usually processed and packaged in an 'autolysed/dried' formula, which may have some impacts on cell surface properties. In this report, we showed using a combination of biochemical, biophysical and molecular methods that the composition of the cell wall of two wine yeast strains was not altered by the autolysis process. In contrast, this process altered the nanomechanical properties as shown by a 2- to 4-fold increased surface roughness and to a higher adhesion to the atomic force microscope tips of the autolysed cells as compared to live yeast cells. Besides, we found that the two strains harboured differences in biomechanical properties that could be due in part to higher levels of mannan in one of them, and to the fact that the surface of this mannan-enriched strain is decorated with highly adhesive patches forming nanodomains. The presence of these nanodomains could be correlated with the upregulation of flocculin encoding FLO11 as well as to higher expression of few other genes encoding cell wall mannoproteins in this mannan-enriched strain as compared to the other strain.
authors.affiliation: Université de Toulouse, INSA, UPS, INP, 135 Avenue de Rangueil, F-31077 Toulouse, France INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, F-31400 Toulouse, France CNRS, UMR5504, F-31400 Toulouse, France CNRS, LAAS, 7 avenue du colonel Roche, F-31400 Toulouse, France Lallemand SAS, 19 Rue des Briquetiers, 31702 Blagnac, France.
authors.forename: Marion
authors.initials: M
authors.lastname: Schiavone
authors.affiliation: Lallemand SAS, 19 Rue des Briquetiers, 31702 Blagnac, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Sieczkowski
authors.affiliation: Lallemand SAS, 19 Rue des Briquetiers, 31702 Blagnac, France.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Castex
authors.affiliation: Université de Toulouse, INSA, UPS, INP, 135 Avenue de Rangueil, F-31077 Toulouse, France CNRS, LAAS, 7 avenue du colonel Roche, F-31400 Toulouse, France.
authors.forename: Etienne
authors.initials: E
authors.lastname: Dague
authors.affiliation: Université de Toulouse, INSA, UPS, INP, 135 Avenue de Rangueil, F-31077 Toulouse, France INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, F-31400 Toulouse, France CNRS, UMR5504, F-31400 Toulouse, France fran_jm@insa-toulouse.fr.
authors.forename: Jean
authors.initials: J
authors.lastname: Marie François
mesh_terms: D001329:Autolysis; D055592:Biophysical Phenomena; D002448:Cell Adhesion; D002473:Cell Wall / Q000502:physiology*; D007218:Industrial Microbiology; D018625:Microscopy, Atomic Force; D012441:Saccharomyces cerevisiae / Q000502:physiology*; D013499:Surface Properties
keywords: atomic force microscopy; autolysis process; cell surface; cell wall; chitin; β-glucans