Anammox Planctomycetes have a peptidoglycan cell wall

• Published in: Nature communications Vol. 6; no. 1; p. 6878
• Main Authors: van Teeseling, Muriel C F, Mesman, Rob J, Kuru, Erkin, Espaillat, Akbar, Cava, Felipe, Brun, Yves V, VanNieuwenhze, Michael S, Kartal, Boran, van Niftrik, Laura
• Format: Journal Article
• Language: English
• Published: England Nature Publishing Group 12.05.2015; Nature Pub. Group
• Subjects: Ammonium Compounds - metabolism; Anaerobiosis; Cell Wall - chemistry; Cell Wall - metabolism; Oxidation-Reduction; Peptidoglycan - chemistry; Peptidoglycan - metabolism; Planctomycetales - classification; Planctomycetales - cytology; Planctomycetales - physiology
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms7878

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.