Proposed structure for brain adenylate cyclase purified using blue dextran–Sepharose chromatography

Abstract

WE have recently shown¹ that blue dextran–Sepharose affinity chromatography can be used to advantage to abbreviate markedly the purification procedures for soluble enzymes whose nucleoside phosphate binding sites are constructed by a supersecondary structure called the NAD-domain. Preliminary measurements using lactate dehydrogenase indicated that affinity chromatography with blue dextran–Sepharose can also be done in the presence of various non-ionic detergents used to solubilise membrane proteins. Here we describe the use of blue dextran–Sepharose affinity chromatography for the purification of the membrane-bound hormone-responsive enzyme, adenylate cyclase, and propose a new structure for the membrane complex which does not contain a separate hormone receptor protein.