The 102 kDa chicken liver acid phosphatase: dimeric structure, glycoprotein nature and immunological properties

In this study we isolated a highly purified, homogeneous high molecular weight (HMW) AcPase (Mr 102 kDa) from the chicken liver. This enzyme was shown to be a slightly acidic (pI 5.0-6.1), dimeric sialoglycoenzyme, composed of two equivalent subunits. Its sugar moiety, characterized by interactions with specific lectins, was shown to be composed of hybrid and complex type of carbohydrate chains. Heterogeneity of the high molecular weight AcPase arising from variations of the sugar components was demonstrated by isoelectric focusing, followed by reactions of the isoelectric components with specific lectins on NC membranes. Structural relationship based on immunological similarities was shown between the HMW AcPases from carp, frog, and chicken livers.