title: Quantitative proteomic analysis of extracellular matrix extracted from mono- and dual-species biofilms of Fusobacterium nucleatum and Porphyromonas gingivalis.
abstract: The Gram-negative bacteria Fusobacterium nucleatum and Porphyromonas gingivalis are members of a complex dental biofilm associated with periodontal disease. In this study, we cultured F. nucleatum and P. gingivalis as mono- and dual-species biofilms, and analyzed the protein composition of the biofilms extracellular polymeric matrix (EPM) by high-resolution liquid chromatography-tandem mass spectrometry. Label-free quantitative proteomic analysis was used for identification of proteins and sequence-based functional characterization for their classification and prediction of possible roles in EPM. We identified 542, 93 and 280 proteins in the matrix of F. nucleatum, P. gingivalis, and the dual-species biofilm, respectively. Nearly 70% of all EPM proteins in the dual-species biofilm originated from F. nucleatum, and a majority of these were cytoplasmic proteins, suggesting an enhanced lysis of F. nucleatum cells. The proteomic analysis also indicated an interaction between the two species: 22 F. nucleatum proteins showed differential levels between the mono and dual-species EPMs, and 11 proteins (8 and 3 from F. nucleatum and P. gingivalis, respectively) were exclusively detected in the dual-species EPM. Oxidoreductases and chaperones were among the most abundant proteins identified in all three EPMs. The biofilm matrices in addition contained several known and hypothetical virulence proteins, which can mediate adhesion to the host cells and disintegration of the periodontal tissues. This study demonstrated that the biofilm matrix of two important periodontal pathogens consists of a multitude of proteins whose amounts and functionalities vary largely. Relatively high levels of several of the detected proteins might facilitate their potential use as targets for the inhibition of biofilm development.
authors.affiliation: The Gade Research Group for Infection and Immunity, Department of Clinical Science, Faculty of Medicine and Dentistry, University of Bergen, Bergen, Norway. Electronic address: Marwan.Mohammed@uib.no.
authors.forename: Marwan Mansoor Ali
authors.initials: MMA
authors.lastname: Mohammed
authors.affiliation: The Gade Research Group for Infection and Immunity, Department of Clinical Science, Faculty of Medicine and Dentistry, University of Bergen, Bergen, Norway. Electronic address: Veronika.Kucharova@uib.no.
authors.forename: Veronika Kuchařová
authors.initials: VK
authors.lastname: Pettersen
authors.affiliation: The Gade Research Group for Infection and Immunity, Department of Clinical Science, Faculty of Medicine and Dentistry, University of Bergen, Bergen, Norway. Electronic address: Audun.Nerland@uib.no.
authors.forename: Audun H
authors.initials: AH
authors.lastname: Nerland
authors.affiliation: The Gade Research Group for Infection and Immunity, Department of Clinical Science, Faculty of Medicine and Dentistry, University of Bergen, Bergen, Norway. Electronic address: Harald.Wiker@uib.no.
authors.forename: Harald G
authors.initials: HG
authors.lastname: Wiker
authors.affiliation: The Gade Research Group for Infection and Immunity, Department of Clinical Science, Faculty of Medicine and Dentistry, University of Bergen, Bergen, Norway. Electronic address: Vidar.Bakken@uib.no.
authors.forename: Vidar
authors.initials: V
authors.lastname: Bakken
mesh_terms: D001426:Bacterial Proteins / Q000032:analysis*; D018441:Biofilms / Q000254:growth & development*; D002853:Chromatography, Liquid; D019295:Computational Biology; D005109:Extracellular Matrix / Q000737:chemistry*; D016967:Fusobacterium nucleatum / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D016966:Porphyromonas gingivalis / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D020543:Proteome / Q000032:analysis*; D040901:Proteomics; D053719:Tandem Mass Spectrometry
chemical_list: D001426:Bacterial Proteins; D020543:Proteome
keywords: Bacterial biofilms; Extracellular polymeric matrix; Fusobacterium nucleatum; Label-free quantitative proteomics; Porphyromonas gingivalis; Tandem mass spectrometry