SEPARATION OF THE VALYL-LEUCYL- AND VALYL-GLUTAMYL-POLYPEPTIDE CHAINS OF HORSE GLOBIN BY FRACTIONAL PRECIPITATION AND COLUMN CHROMATOGRAPHY

Abstract

Horse globin has been fractionated into two components by stepwise addition of acid acetone to an acidified globin solution and by gradient elution with urea from a carboxylic-type ion exchange resin at low pH.The components obtained by both methods are similar to those prepared earlier by electrophoresis. They have similar molecular weights (about 16,000) and appear to be present in nearly equal amounts. One has the N-terminal sequence valyl-leucyl- and the other valyl-glutamyl-. They differ electrokinetically and in other properties.