Physicochemical properties of the soluble Mn2+-dependent adenylate cyclase in the blue fox testis

Physicochemical properties of the soluble Mn2+-dependent adenylate cyclase (MnAC) in the blue fox testis were examined. MnAC activity in the cytosol fraction (106,000 g) migrated in a linear sucrose gradient as a single peak with a sedimentation coefficient (S20,W) of 4.2 Gel filtration on a Sephadex G-200 column revealed an Einstein-Stokes radius of 28 A and a frictional ratio of 1.15, indicating a molecular weight of approximately 51,000. The MnAC migrated as a single peak of activity during polyacrylamide gel electrophoresis with an Rf of 0.52. The isoelectric point (pI) estimated by isoelectric focusing was 5.5.