title: Alginate production affects Pseudomonas aeruginosa biofilm development and architecture, but is not essential for biofilm formation.
abstract: Extracellular polymers can facilitate the non-specific attachment of bacteria to surfaces and hold together developing biofilms. This study was undertaken to qualitatively and quantitatively compare the architecture of biofilms produced by Pseudomonas aeruginosa strain PAO1 and its alginate-overproducing (mucA22) and alginate-defective (algD) variants in order to discern the role of alginate in biofilm formation. These strains, PAO1, Alg+ PAOmucA22 and Alg- PAOalgD, tagged with green fluorescent protein, were grown in a continuous flow cell system to characterize the developmental cycles of their biofilm formation using confocal laser scanning microscopy. Biofilm Image Processing (BIP) and Community Statistics (COMSTAT) software programs were used to provide quantitative measurements of the two-dimensional biofilm images. All three strains formed distinguishable biofilm architectures, indicating that the production of alginate is not critical for biofilm formation. Observation over a period of 5 days indicated a three-stage development pattern consisting of initiation, establishment and maturation. Furthermore, this study showed that phenotypically distinguishable biofilms can be quantitatively differentiated.
authors.affiliation: Department of Biological Sciences1 and School of Computer Science2, Florida International University, Miami, FL 33199, USA 3Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA 23298, USA 4Section of Molecular Microbiology, The Technical University of Denmark, DK-2800 Lyngby, Denmark 5Department of Clinical Microbiology, University Hospital of Copenhagen, DK-2100 Copenhagen, Denmark.
authors.forename: Andres Plata
authors.initials: AP
authors.lastname: Stapper
authors.affiliation: Department of Biological Sciences1 and School of Computer Science2, Florida International University, Miami, FL 33199, USA 3Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA 23298, USA 4Section of Molecular Microbiology, The Technical University of Denmark, DK-2800 Lyngby, Denmark 5Department of Clinical Microbiology, University Hospital of Copenhagen, DK-2100 Copenhagen, Denmark.
authors.forename: Giri
authors.initials: G
authors.lastname: Narasimhan
authors.affiliation: Department of Biological Sciences1 and School of Computer Science2, Florida International University, Miami, FL 33199, USA 3Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA 23298, USA 4Section of Molecular Microbiology, The Technical University of Denmark, DK-2800 Lyngby, Denmark 5Department of Clinical Microbiology, University Hospital of Copenhagen, DK-2100 Copenhagen, Denmark.
authors.forename: Dennis E
authors.initials: DE
authors.lastname: Ohman
authors.affiliation: Department of Biological Sciences1 and School of Computer Science2, Florida International University, Miami, FL 33199, USA 3Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA 23298, USA 4Section of Molecular Microbiology, The Technical University of Denmark, DK-2800 Lyngby, Denmark 5Department of Clinical Microbiology, University Hospital of Copenhagen, DK-2100 Copenhagen, Denmark.
authors.forename: Johnny
authors.initials: J
authors.lastname: Barakat
authors.affiliation: Department of Biological Sciences1 and School of Computer Science2, Florida International University, Miami, FL 33199, USA 3Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA 23298, USA 4Section of Molecular Microbiology, The Technical University of Denmark, DK-2800 Lyngby, Denmark 5Department of Clinical Microbiology, University Hospital of Copenhagen, DK-2100 Copenhagen, Denmark.
authors.forename: Morten
authors.initials: M
authors.lastname: Hentzer
authors.affiliation: Department of Biological Sciences1 and School of Computer Science2, Florida International University, Miami, FL 33199, USA 3Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA 23298, USA 4Section of Molecular Microbiology, The Technical University of Denmark, DK-2800 Lyngby, Denmark 5Department of Clinical Microbiology, University Hospital of Copenhagen, DK-2100 Copenhagen, Denmark.
authors.forename: Søren
authors.initials: S
authors.lastname: Molin
authors.affiliation: Department of Biological Sciences1 and School of Computer Science2, Florida International University, Miami, FL 33199, USA 3Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA 23298, USA 4Section of Molecular Microbiology, The Technical University of Denmark, DK-2800 Lyngby, Denmark 5Department of Clinical Microbiology, University Hospital of Copenhagen, DK-2100 Copenhagen, Denmark.
authors.forename: Arsalan
authors.initials: A
authors.lastname: Kharazmi
authors.affiliation: Department of Biological Sciences1 and School of Computer Science2, Florida International University, Miami, FL 33199, USA 3Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA 23298, USA 4Section of Molecular Microbiology, The Technical University of Denmark, DK-2800 Lyngby, Denmark 5Department of Clinical Microbiology, University Hospital of Copenhagen, DK-2100 Copenhagen, Denmark.
authors.forename: Niels
authors.initials: N
authors.lastname: Høiby
authors.affiliation: Department of Biological Sciences1 and School of Computer Science2, Florida International University, Miami, FL 33199, USA 3Department of Microbiology and Immunology, Virginia Commonwealth University, Richmond, VA 23298, USA 4Section of Molecular Microbiology, The Technical University of Denmark, DK-2800 Lyngby, Denmark 5Department of Clinical Microbiology, University Hospital of Copenhagen, DK-2100 Copenhagen, Denmark.
authors.forename: Kalai
authors.initials: K
authors.lastname: Mathee
mesh_terms: D000464:Alginates; D018441:Biofilms / Q000254:growth & development*; D005798:Genes, Bacterial; D017930:Genes, Reporter; D020723:Glucuronic Acid / Q000096:biosynthesis* / Q000502:physiology*; D049452:Green Fluorescent Proteins; D006603:Hexuronic Acids; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D018613:Microscopy, Confocal; D009154:Mutation; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis / Q000502:physiology; D011550:Pseudomonas aeruginosa / Q000378:metabolism* / Q000502:physiology; D013194:Staining and Labeling
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D008164:Luminescent Proteins; D011135:Polysaccharides, Bacterial; D049452:Green Fluorescent Proteins; D020723:Glucuronic Acid