Separation of serum albumin into two fractions

Abstract

Separation of the albumin fraction of horse serum into (a) a crystalline protein (crystalbumin) free from carbohydrate, and (b) a glycoprotein containing about 10% of polysaccharide, was repeated. The properties of (b) suggest that it is a new serum protein; the name seroglycoid is suggested for it. It has a lower cystine content, higher trypto-phan, lower free amino-N and lower rotatory power than crystalbumin. When a mixture of seroglycoid with other serum proteins is heated it is carried down with the coagulum; when isolated it is not coagulated on heating. Of the albumin fraction of horse serum about 1/8 of the protein present is seroglycoid.