Is a virulence factor capable of inducing inflammation in the lower respiratory tract, by increasing tumor necrosis factor alpha (TNF-alpha) concentration in the lungs. Also appears to have other functions important in virulence in models of pneumonia and septicemia. Binds 1 zinc ion per subunit. The Gram-positive cell-wall anchor motif LPXTG is located in the N-terminal part, in contrast to such motifs in other known streptococcal and staphylococcal proteins. The protease could be cleaved by the sortase and anchored in the membrane via the two potential N-terminal transmembrane domains, whereas the propeptide located prior to the LPXTG motif would remain attached to the cell wall peptidoglycan by an amide bond. Belongs to the peptidase M26 family. Was originally (PubMed:10792723) thought to control translocation of choline-binding proteins to the cell surface but PubMed:11260480 failed to confirm this observation. The conflicting observations could be explained by the fact that the mutant strain used in PubMed:10792723 lacked capsule.