Sialic acids placenta

Beckman et al. (28) have studied the electrophoretic separation of the acid phosphatase activity in tissue extracts on starch gel at pH 8. They described four electrophoretic bands A, B, C, and D. Table IV (28) shows the distribution of activity in different organ extracts. The ABD pattern predominated in kidney BD in liver, intestine, heart, and skeletal muscle B in skin and D in pancreas. The C component was present in a large number of placentae but not in other adult organs. All four electrophoretic components were inhibited by d-(- -)-tartrate A contained sialic acid, D had a lower pH optimum and was more heat resistant than A, B, and C. Components C and D showed parallel electrophoretic behavior. In human skin fibroblasts grown in tissue culture, the acid phosphatase was generally high and the most common pattern was BD. Almost every culture showed some activity. The BD... 

Alkaline phosphatase is an enzyme of the cellular membranes. Its isoforms can be found in liver, digestive tract, placenta, and some tumor tissues. Bone isoform, BALP, is a membrane enzyme of the osteoblasts. Bone, liver, and intestinal isoforms are the posttranslational modifications of the same isoenzyme exprimed by the same gene, and the difference among them lies in various ways of reaction with a saccharide component, sialic acid (M9). 

Ahmed, H., and Gabius, H.-J., 1989, Purification and properties of a Ca +-independent sialic acid binding lectin from human placenta with preferential affinity to O-acetylsialic acids, J. Biol. Chem. 264 18673-18678. 

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