Mycoplasma pneumoniae (Mpn) is responsible for 15-20% of cases of community-acquired pneumonia. Up to 25% of infected patients develop extrapulmonary complications that can affect neurological, musculoskeletal, haematological and cardiovascular sites. An extracellular extension called the attachment organelle mediates attachment to the respiratory epithelium via the P1 and P30 adhesins. Vaccines incorporating both adhesins unfortunately exacerbate disease and a successful vaccine is yet to be developed. Our surfaceome studies identify about 160 proteins on the surface of Mpn including a number that lack signal secretion sequences. One of these, elongation factor Tu (Ef-Tu), is a protein that moonlights on the surface of Gram positive and Gram negative pathogens. Dallo et al., (2002¹) used immunogold EM microscopy to confirm Ef-Tu on the cell surface of Mpn and also described its ability to bind fibronectin (Fn). Subsequent studies identified two Fn binding motifs and six key amino acids in those regions that are needed to bind Fn in Ef-Tu (Balasubramanian et al., 2008², 2009³). Notably, whole cell Labelling studies that target N-terminal amino acids identified nine neo-N-termini within Ef-Tu. LC-MS/MS analysis of protein spots separated by 2D SDS-PAGE and analysis of eluents from affinity chromatography columns loaded with fetuin, actin, plasminogen, heparin and Fn as bait has allowed us to map 15 putative cleavage fragments of Ef-Tu. Preliminary microscale thermophoresis experiments indicate that purified recombinant Ef-Tu binds heparin, plasminogen and actin and further experiments are underway to validate interactions between Ef-Tu and other host molecules implicated in our affinity studies. Our data indicates that Ef-Tu is a multifunctional adhesin that is processed into functional domains on the cell surface of Mpn.