Structural identification of ladderane and other membrane lipids of planctomycetes capable of anaerobic ammonium oxidation (anammox) Jaap S. Sinninghe Damste´ 1, W. Irene C. Rijpstra1, Jan A. J. Geenevasen2, Marc Strous3 and Mike S. M. Jetten3 1 Royal Netherlands Institute for Sea Research (NIOZ), Department of Marine Biogeochemistry and Toxicology, Texel, the Netherlands 2 van ‘t Hoff Institute for Molecular Science (HIMS), University of Amsterdam, the Netherlands 3 Department of Microbiology, Institute of Water and Wetland Research, Radboud University Nijmegen, the Netherlands Keywords The membrane lipid composition of planctomycetes capable of the an- ether lipids; fatty acids; mass spectrometry; aerobic oxidation of ammonium (anammox), i.e. Candidatus ‘Brocadia mixed glycerol ester/ether lipids; NMR anammoxidans’ and Candidatus ‘Kuenenia stuttgartiensis’, was shown to be composed mainly of so-called ladderane lipids. These lipids are com- Correspondence J. S. Sinninghe Damste´ , Royal Netherlands prised of three to five linearly concatenated cyclobutane moieties with cis Institute for Sea Research (NIOZ), ring junctions, which occurred as fatty acids, fatty alcohols, alkyl glycerol Department of Marine Biogeochemistry and monoethers, dialkyl glycerol diethers and mixed glycerol ether ⁄ esters. The Toxicology, PO Box 59, 1790 AB Den Burg, highly strained ladderane moieties were thermally unstable, which resulted the Netherlands in breakdown during their analysis with GC. This was shown by isolation Fax: +31 222 319 674 of a thermal product of these ladderanes and subsequent analysis with Tel: +31 222 369 550 two-dimensional NMR techniques. Comprehensive MS and relative retent- E-mail:
[email protected] ion time data for all the encountered ladderane membrane lipids is repor- (Received 26 May 2005, revised 23 June ted, allowing the identification of ladderanes in other bacterial cultures and 2005, accepted 1 July 2005) in the environment.