PPase-2B is a heterodimeric enzyme composed of a 19kDa calcium-binding subunit and a catalytic subunit (61kDa) that binds calmodulin. PPase-2B was originally identified based on its calcium- and calmodulin-dependent activity toward phosphorylase kinase and inhibitor-1. PPase-2B is identical to the brain protein calcineurin, which constitutes up to 1% of total brain protein. The immunosuppressive drugs FK-506 and cyclosporin A inhibit PPase-2B activity in immune cells, implicating a role for this enzyme in regulation of the immune system. PPase-2B also plays a major role in regulating secretory functions of a variety of cells.
PPase-2B is less sensitive to okadaic acid than PPase-2A and PPase-1, requiring micromolar concentrations of okadaic acid for inhibition. It is not inhibited by Inhibitor-1 or Inhibitor-2. Promega PPase-2B is isolated from bovine brain.Unit Definfition: One unit is the amount of PPase-2B required to release 1nmol of phosphate per minute at 30°C, using p-nitrophenyl phosphate (PNPP) as the substrate.
Storage Buffer: 50mM Tris-HCl (pH 7.0), 50% glycerol.