Mycoplasma hyopneumoniae is the causative pathogen of porcine enzootic pneumonia, an economically significant disease that disrupts the mucociliary escalator in the swine respiratory tract. Expression of Mhp107, a P97 paralog encoded by the gene mhp107, was confirmed using ESI-MS/MS. To investigate the function of Mhp107, three recombinant proteins, F1 Mhp107, F2 Mhp107, and F3 Mhp107, spanning the N-terminal, central, and C-terminal regions of Mhp107 were constructed. Colonization of swine by M. hyopneumoniae requires adherence of the bacterium to ciliated cells of the respiratory tract. Recent studies have identified a number of M. hyopneumoniae adhesins that bind heparin, fibronectin, and plasminogen. F1 Mhp107 was found to bind porcine heparin (K D ∼90 nM) in a dose-dependent and saturable manner, whereas F3 Mhp107 bound fibronectin (K D ∼180 nM) at physiologically relevant concentrations. F1 Mhp107 also bound porcine plasminogen (K D = 24 nM) in a dose-dependent and physiologically relevant manner. Microspheres coated with F3 Mhp107 mediate adherence to porcine kidney epithelial-like (PK15) cells, and all three recombinant proteins (F1 Mhp107-F3 Mhp107) bound swine respiratory cilia. Together, these findings indicate that Mhp107 is a member of the multifunctional M. hyopneumoniae adhesin family of surface proteins and contributes to both adherence to the host and pathogenesis. © 2011 by The American Society for Biochemistry and Molecular Biology, Inc.