The membrane lipid composition of planctomycetes capable of the an-aerobic oxidation of ammonium (anammox), . Candidatus‘Brocadia anammoxidans’ and Candidatus‘Kuenenia stuttgartiensis’, was shown to be composed mainly of so-called ladderane lipids. These lipids are com-prised of three to five linearly concatenated cyclobutane moieties withcis ring junctions, which occurred as fatty acids, fatty alcohols, alkyl glycerol monoethers, dialkyl glycerol diethers and mixed glycerol ether⁄esters. .
