Figure 1
Cleavage map of the P1 adhesin. The full length proteoform (1627 amino acids) is shown as the black bar with cleavage sites above and fragments below this bar. Cleavage sites identified from dimethyl labelling and semi-tryptic sites are shown as the blue and red arrows, respectively. Sequences where these cleavage sites occur are also shown. Putative heparin binding sites (Hep, blue boxes, motif: X-[HRK]-[HRK]-X-[HRK]-X), heparan sulfate binding sites (HepS, blue boxes, motif: X-[HRK]-X-[HRK]-[HRK]-X), clusters of basic residues (HepB, blue boxes, motifs: X-[HRK]-X(0,2)-[HRK]-X(0,2)-[HRK]-X or X-[HRK]-X(1,3)-[HRK]-X(1,3)-[HRK]-X), and transmembrane domains (TmD, yellow boxes, TmD1 predicted by TMpred66, TmD2 previously predicted32, TmD3 previously predicted36, and TmD4 previously predicted in a P1 paralog73) are shown within the black bar. Putative transmembrane domains and the location of 15 subregions of P1 (grey ‘RP’ boxes) expressed as recombinant proteins from an earlier study55 are shown. Predicted disordered regions appear as purple boxes in the grey bar. Acidic and basic regions within P1 are identified as yellow and blue bars, respectively. Peptides released from surface shaving experiments and identified by mass spectrometry are shown in the light green boxes within the grey bar. Grey bars represent fragments of P1 identified during SDS-PAGE of whole cell lysates. Red bars represent fragments of P1 recovered from lysates of M. pneumoniae that have their surface proteins labelled with biotin (surface exposed fragments of P1). Peptides identified by mass spectrometry of P1 fragments isolated from affinity chromatography of fetuin (yellow bars), actin (light blue bars), A549 surface protein complexes (orange bars), fibronectin (green bars), heparin (blue bars), and plasminogen (purple bars) are shown.
