title: Proteomic analysis of the adaptative response of Mucor spp. to cheese environment.
abstract: In the cheese industry context, Mucor species exhibit an ambivalent behavior as some species are essential "technological" organisms of some cheeses while others can be spoiling agents. Previously, we observed that cheese "technological" species exhibited higher optimal growth rates on cheese related matrices than on synthetic media. This growth pattern combined with morphological differences raise the question of their adaptation to cheese. In this study, using a comparative proteomic approach, we described the metabolic pathways of three Mucor strains considered as "technological" or "contaminant" in the cheese environment (M. lanceolatus UBOCC-A-109153, M. racemosus UBOCC-A-109155, M. circinelloides CBS 277-49) as well as a non-cheese related strain (M. endophyticus CBS 385-95). Overall, 15.8 to 19.0% of the proteomes showed a fold change ≥1.6 in Potato Dextrose Agar (PDA) versus Cheese Agar (CA), a cheese mimicking-medium. The 289 differentially expressed proteins identified by LC MS-MS analysis were mostly assigned to energy and amino-acid metabolisms in PDA whereas a higher diversity of biological processes was observed for cheese related strains in CA. Surprisingly, the vast majority (72.9%) of the over-accumulated proteins were different according to the considered medium and strain. These results strongly suggest that the observed better adaptative response of "technological" strains to cheese environment is mediated by species-specific proteins.
  
  
  
  The Mucor genus consists of a multitude of poorly known species. In the food context, few species are known for their positive role in the production of various food products, including cheese, while others are spoiling agents. The present study focused on the analysis of morphological and proteome differences of various Mucor spp. representative strains known as either positively (hereafter referred as "technological") or negatively (hereafter referred as "contaminant") associated with cheese or non-related to cheese (endophyte) on two different media, a synthetic medium and a cheese-mimicking medium. The main goal was to assess if adaptative traits of "technological" strains to the cheese environment could be identified. This work was based on observations we did in a recently published physiological study (Morin-Sardin et al., 2016). One of the important innovative aspects lies in the use for the first time of an extensive 2-DE approach to compare proteome variations for 4 strains on two different media. Results obtained offered an insight in the metabolic mechanisms associated with growth on a given medium and showed that adaptation to cheese environment is probably supported by species-specific proteins. The obtained data represent an essential step point for more targeted studies at the genomic and transcriptomic levels.
authors.affiliation: Université de Brest, EA 3882 Laboratoire Universitaire de Biodiversité et d'Ecologie Microbienne, IBSAM, ESIAB, Technopôle Brest-Iroise, 29280 Plouzané, France.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Morin-Sardin
authors.affiliation: Université de Brest, EA 3882 Laboratoire Universitaire de Biodiversité et d'Ecologie Microbienne, IBSAM, ESIAB, Technopôle Brest-Iroise, 29280 Plouzané, France.
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Jany
authors.affiliation: Université de Brest, UMR 6539, Laboratoire des Sciences de l'Environnement Marin, LEMAR CNRS/UBO/IRD/Ifremer, Institut Universitaire Européen de la Mer, Université de Bretagne Occidentale, 29280 Plouzané, France.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Artigaud
authors.affiliation: Université de Brest, UMR 6539, Laboratoire des Sciences de l'Environnement Marin, LEMAR CNRS/UBO/IRD/Ifremer, Institut Universitaire Européen de la Mer, Université de Bretagne Occidentale, 29280 Plouzané, France.
authors.forename: Vianney
authors.initials: V
authors.lastname: Pichereau
authors.affiliation: Plateforme Proteogen SFR ICORE, Université de Caen Basse-Normandie, 14032 Caen Cedex, France.
authors.forename: Benoît
authors.initials: B
authors.lastname: Bernay
authors.affiliation: Université de Brest, EA 3882 Laboratoire Universitaire de Biodiversité et d'Ecologie Microbienne, IBSAM, ESIAB, Technopôle Brest-Iroise, 29280 Plouzané, France.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Coton
authors.affiliation: Université de Brest, EA 3882 Laboratoire Universitaire de Biodiversité et d'Ecologie Microbienne, IBSAM, ESIAB, Technopôle Brest-Iroise, 29280 Plouzané, France. Electronic address: stephanie.madec@univ-brest.fr.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Madec
mesh_terms: D000222:Adaptation, Physiological; D002611:Cheese / Q000382:microbiology*; D005516:Food Microbiology; D005656:Fungal Proteins / Q000032:analysis / Q000378:metabolism; D053858:Metabolic Networks and Pathways; D009089:Mucor / Q000737:chemistry* / Q000254:growth & development / Q000502:physiology; D040901:Proteomics / Q000379:methods*; D013045:Species Specificity
chemical_list: D005656:Fungal Proteins
keywords: Adaptative response; Cheese; Mucor; Proteome; “Technological” species