title: Determining the bacterial cell biology of Planctomycetes.
abstract: Bacteria of the phylum Planctomycetes have been previously reported to possess several features that are typical of eukaryotes, such as cytosolic compartmentalization and endocytosis-like macromolecule uptake. However, recent evidence points towards a Gram-negative cell plan for Planctomycetes, although in-depth experimental analysis has been hampered by insufficient genetic tools. Here we develop methods for expression of fluorescent proteins and for gene deletion in a model planctomycete, Planctopirus limnophila, to analyse its cell organization in detail. Super-resolution light microscopy of mutants, cryo-electron tomography, bioinformatic predictions and proteomic analyses support an altered Gram-negative cell plan for Planctomycetes, including a defined outer membrane, a periplasmic space that can be greatly enlarged and convoluted, and an energized cytoplasmic membrane. These conclusions are further supported by experiments performed with two other Planctomycetes, Gemmata obscuriglobus and Rhodopirellula baltica. We also provide experimental evidence that is inconsistent with endocytosis-like macromolecule uptake; instead, extracellular macromolecules can be taken up and accumulate in the periplasmic space through unclear mechanisms.
authors.affiliation: Leibniz Institute DSMZ, Inhoffenstraße 7b, 38124 Braunschweig, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Boedeker
authors.affiliation: Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany.
authors.forename: Margarete
authors.initials: M
authors.lastname: Schüler
authors.affiliation: Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359 Bremen, Germany.
authors.forename: Greta
authors.initials: G
authors.lastname: Reintjes
authors.affiliation: Leibniz Institute DSMZ, Inhoffenstraße 7b, 38124 Braunschweig, Germany.
authors.forename: Olga
authors.initials: O
authors.lastname: Jeske
authors.affiliation: Department of Microbiology, Radboud University, Heyendaalseweg 135, NL-6525 AJ Nijmegen, Netherlands.|Department of Cellular Microbiology, Philipps-University Marburg, Faculty of Biology, Hans-Meerwein-Straße 4, 35043 Marburg, Germany.
authors.forename: Muriel C F
authors.initials: MC
authors.lastname: van Teeseling
authors.affiliation: Leibniz Institute DSMZ, Inhoffenstraße 7b, 38124 Braunschweig, Germany.
authors.forename: Mareike
authors.initials: M
authors.lastname: Jogler
authors.affiliation: Leibniz Institute DSMZ, Inhoffenstraße 7b, 38124 Braunschweig, Germany.
authors.forename: Patrick
authors.initials: P
authors.lastname: Rast
authors.affiliation: Leibniz Institute DSMZ, Inhoffenstraße 7b, 38124 Braunschweig, Germany.
authors.forename: Daniela
authors.initials: D
authors.lastname: Borchert
authors.affiliation: Department of Cell biology and Biotechnology, CABD, Pablo de Olavide University-CSIC, Carretera de Utrera km1, 41013 Sevilla, Spain.
authors.forename: Damien P
authors.initials: DP
authors.lastname: Devos
authors.affiliation: Helmholtz Center for Infection Research GmbH, Inhoffenstraße 7, 38124 Braunschweig, Germany.|Department of Microbial Proteomics, Technical University Braunschweig, Institute for Microbiology, Spielmannstraße 7, 38106 Braunschweig, Germany.
authors.forename: Martin
authors.identifier: 0000-0002-7289-3915
authors.initials: M
authors.lastname: Kucklick
authors.affiliation: Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany.
authors.forename: Miroslava
authors.initials: M
authors.lastname: Schaffer
authors.affiliation: Department of Microbiology and Immunobiology, Harvard Medical School, Boston, Massachusetts, 02115, USA.
authors.forename: Roberto
authors.initials: R
authors.lastname: Kolter
authors.affiliation: Department of Microbiology, Radboud University, Heyendaalseweg 135, NL-6525 AJ Nijmegen, Netherlands.
authors.forename: Laura
authors.identifier: 0000-0002-7011-7234
authors.initials: L
authors.lastname: van Niftrik
authors.affiliation: Helmholtz Center for Infection Research GmbH, Inhoffenstraße 7, 38124 Braunschweig, Germany.|Department of Microbial Proteomics, Technical University Braunschweig, Institute for Microbiology, Spielmannstraße 7, 38106 Braunschweig, Germany.
authors.forename: Susanne
authors.initials: S
authors.lastname: Engelmann
authors.affiliation: Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359 Bremen, Germany.
authors.forename: Rudolf
authors.initials: R
authors.lastname: Amann
authors.affiliation: Helmholtz Center for Infection Research GmbH, Inhoffenstraße 7, 38124 Braunschweig, Germany.
authors.forename: Manfred
authors.initials: M
authors.lastname: Rohde
authors.affiliation: Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany.
authors.forename: Harald
authors.initials: H
authors.lastname: Engelhardt
authors.affiliation: Leibniz Institute DSMZ, Inhoffenstraße 7b, 38124 Braunschweig, Germany.|Department of Microbiology, Radboud University, Heyendaalseweg 135, NL-6525 AJ Nijmegen, Netherlands.
authors.forename: Christian
authors.initials: C
authors.lastname: Jogler
mesh_terms: D000641:Ammonia / Q000378:metabolism; D004705:Endocytosis; D023281:Genomics; D010084:Oxidation-Reduction; D010802:Phylogeny; D061328:Planctomycetales / Q000145:classification / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D040901:Proteomics
chemical_list: D000641:Ammonia