title: Anammox Planctomycetes have a peptidoglycan cell wall.
abstract: Planctomycetes are intriguing microorganisms that apparently lack peptidoglycan, a structure that controls the shape and integrity of almost all bacterial cells. Therefore, the planctomycetal cell envelope is considered exceptional and their cell plan uniquely compartmentalized. Anaerobic ammonium-oxidizing (anammox) Planctomycetes play a key role in the global nitrogen cycle by releasing fixed nitrogen back to the atmosphere as N2. Here using a complementary array of state-of-the-art techniques including continuous culturing, cryo-transmission electron microscopy, peptidoglycan-specific probes and muropeptide analysis, we show that the anammox bacterium Kuenenia stuttgartiensis contains peptidoglycan. On the basis of the thickness, composition and location of peptidoglycan in K. stuttgartiensis, we propose to redefine Planctomycetes as Gram-negative bacteria. Our results demonstrate that Planctomycetes are not an exception to the universal presence of peptidoglycan in bacteria.
authors.affiliation: Department of Microbiology, Institute for Water and Wetland Research, Faculty of Science, Radboud University, Nijmegen 6525AJ, The Netherlands.
authors.forename: Muriel C F
authors.initials: MC
authors.lastname: van Teeseling
authors.affiliation: Department of Microbiology, Institute for Water and Wetland Research, Faculty of Science, Radboud University, Nijmegen 6525AJ, The Netherlands.
authors.forename: Rob J
authors.initials: RJ
authors.lastname: Mesman
authors.affiliation: Interdisciplinary Biochemistry Program, Indiana University, Bloomington, Indiana 47405, USA.
authors.forename: Erkin
authors.initials: E
authors.lastname: Kuru
authors.affiliation: Department of Molecular Biology and Laboratory for Molecular Infection Medicine Sweden, Umeå Centre for Microbial Research, Umeå University, Umeå SE-90187, Sweden.
authors.forename: Akbar
authors.initials: A
authors.lastname: Espaillat
authors.affiliation: Department of Molecular Biology and Laboratory for Molecular Infection Medicine Sweden, Umeå Centre for Microbial Research, Umeå University, Umeå SE-90187, Sweden.
authors.forename: Felipe
authors.identifier: 000000015995718X
authors.initials: F
authors.lastname: Cava
authors.affiliation: Department of Biology, Indiana University, Bloomington, Indiana 47405, USA.
authors.forename: Yves V
authors.initials: YV
authors.lastname: Brun
authors.affiliation: Department of Chemistry, Indiana University, Bloomington, Indiana 47405, USA.
authors.forename: Michael S
authors.initials: MS
authors.lastname: VanNieuwenhze
authors.affiliation: 1] Department of Microbiology, Institute for Water and Wetland Research, Faculty of Science, Radboud University, Nijmegen 6525AJ, The Netherlands [2] Department of Biochemistry and Microbiology, Laboratory of Microbiology, Gent University, Gent 9000, Belgium.
authors.forename: Boran
authors.initials: B
authors.lastname: Kartal
authors.affiliation: Department of Microbiology, Institute for Water and Wetland Research, Faculty of Science, Radboud University, Nijmegen 6525AJ, The Netherlands.
authors.forename: Laura
authors.initials: L
authors.lastname: van Niftrik
mesh_terms: D064751:Ammonium Compounds / Q000378:metabolism; D000693:Anaerobiosis; D002473:Cell Wall / Q000737:chemistry / Q000378:metabolism*; D010084:Oxidation-Reduction; D010457:Peptidoglycan / Q000737:chemistry / Q000378:metabolism*; D061328:Planctomycetales / Q000145:classification / Q000166:cytology* / Q000502:physiology*
chemical_list: D064751:Ammonium Compounds; D010457:Peptidoglycan