title: Three-dimensional macromolecular organization of cryofixed Myxococcus xanthus biofilms as revealed by electron microscopic tomography.
abstract: Despite the fact that most bacteria grow in biofilms in natural and pathogenic ecosystems, very little is known about the ultrastructure of their component cells or about the details of their community architecture. We used high-pressure freezing and freeze-substitution to minimize the artifacts of chemical fixation, sample aggregation, and sample extraction. As a further innovation we have, for the first time in biofilm research, used electron tomography and three-dimensional (3D) visualization to better resolve the macromolecular 3D ultrastructure of a biofilm. This combination of superb specimen preparation and greatly improved resolution in the z axis has opened a window in studies of Myxococcus xanthus cell ultrastructure and biofilm community architecture. New structural information on the chromatin body, cytoplasmic organization, membrane apposition between adjacent cells, and structure and distribution of pili and vesicles in the biofilm matrix is presented.
authors.affiliation: Lawrence Berkeley National Laboratory, CA 94720, USA.
authors.forename: Hildur
authors.initials: H
authors.lastname: Palsdottir
authors.forename: Jonathan P
authors.initials: JP
authors.lastname: Remis
authors.forename: Christoph
authors.initials: C
authors.lastname: Schaudinn
authors.forename: Eileen
authors.initials: E
authors.lastname: O'Toole
authors.forename: Renate
authors.initials: R
authors.lastname: Lux
authors.forename: Wenyuan
authors.initials: W
authors.lastname: Shi
authors.forename: Kent L
authors.initials: KL
authors.lastname: McDonald
authors.forename: J William
authors.initials: JW
authors.lastname: Costerton
authors.forename: Manfred
authors.initials: M
authors.lastname: Auer
mesh_terms: D018441:Biofilms / Q000254:growth & development*; D002876:Chromosomes, Bacterial / Q000648:ultrastructure; D022162:Cytoplasmic Vesicles / Q000648:ultrastructure; D055032:Electron Microscope Tomography / Q000379:methods*; D010861:Fimbriae, Bacterial / Q000648:ultrastructure; D021621:Imaging, Three-Dimensional; D016941:Myxococcus xanthus / Q000502:physiology / Q000648:ultrastructure*