F11R and infection: One hour after infection, the level of HA-labeled JAM1 Δ(1–133) in the lower layer was decreased by infection with P. gingivalis, but the level of JAM1 Δ(1–133) K134H R234H was unaffected (Fig 8F), indicating that the K134 and R234 residues of JAM1 were digested by gingipains derived from the upper space.