Acts as a multifunctional adhesin involved in direct interactions with host epithelial cells and host proteins, including vitronectin, laminin and plasminogen. In addition, interaction with serum vitronectin plays an important role in bacterial serum resistance, and conversion of plasminogen to plasmin at the cell surface aids in immune evasion and contributes to bacterial virulence. Induces a pro-inflammatory epithelial cell response, leading to interleukin-8 (IL-8) secretion and up-regulation of ICAM1. Homodimer. Interacts with host vitronectin, laminin and plasminogen. Can interact with both immobilized and soluble vitronectin. Mutant displays a reduced binding to vitronectin, laminin, plasminogen and epithelial cells, and is more sensitive to killing by human serum compared with the wild type.