1.B.57 The Legionella Major-Outer Membrane Protein (LM-OMP) Family

The genome of Legionella pneumophila reveals the presence of a large number of genes coding for eukaryotic-like proteins. Khemiri et al. (2008) identified proteins in L. pneumophila whose sequences share similarities with those of eukaryotic polypeptides (lpg0211, lpg1974 and lpg1982). In eukaryotes, the corresponding proteins (PBR, peripheral benzodiazepine receptor; VDAC, voltage-dependant anion channel; and CypD, cyclophilin D) participate in the formation of the mammalian mitochondrial permeability transition pore (MPTP), a complex involved in cell apoptosis. Lpg1974 is a major OMP of Legionella and may be a porin. Multiple paralogues are sometimes formed in a single bacterium.