An improved isolation procedure for carbonic anhydrase C from red cell lysate.

An effective isolation of carbonic anhydrase C (CA-C) from red cell lysate was described. The lysate dialyzed against 0.0175 M phosphate buffer pH 6.3 was applied onto a CM-Sephadex column equilibrated with the same buffer. The elution was performed with the starting buffer and 0.1 M dibasic potassium phosphate containing 0.14 M NaCl. The hemoglobin fraction eluted with the second eluant was applied onto a DEAE-cellulose column and eluted with 0.2 M glycine containing 0.01 percent KCN, resulting in complete isolation of CA-C at high recovery rate. For the preparation in a large scale, the hemoglobin fraction prepared from CM-Sephadex semi-batch-type chromatography was treated with cold ethanol and chloroform. The purity of these preparations was confirmed by polyacrylamide gel disc electrophoresis and immunoelectrophoresis.