Isolation and partial characterization of bovine periodontal ligament alkaline phosphatase

An alkaline phosphatase which binds to hyaluronate with a high affinity has been extracted from the bovine periodontal ligament and purified. The procedure consisted of extraction with a 10 mM Tris/Mg buffer containing 0.1% Nonidet P40, chromatography on a hyaluronate-conjugated Affi-Gel 15, and fast protein liquid chromatography. The hyaluronate-binding alkaline phosphatase has an apparent molecular weight of 110,000, contained sialic acid and was more stable to heat treatment than were two other species (Mr = 120,000 and 130,000) extracted from PDL. The heat stability and influence of inhibitors on its activity show that the hyaluronate-binding alkaline phosphatase of periodontal ligament was similar to the bone alkaline phosphatase.