title: Concanavalin A perturbation of membrane enzymes of mammary gland.
abstract: The plant lectin concanavalin A (Con A) specifically inactivates the 5'-nucleotidase of a plasma membrane-enriched fraction from lactating mammary gland. The lectin also causes an activation of the membrane Mg++-ATPase, but does not affect galactosyltransferase or alkaline phosphatase. The enzyme perturbations are prevented by alpha-methylmannoside, an inhibitor of Con A binding, indicating that specific binding to carbohydrate structures rather than nonspecific protein-protein interaction is involved. Solubilization of the 5'-nucleotidase in detergents (0.2% Triton X-100 or 1% deoxycholate) does not prevent Con A inactivation, indicating that incorporation into the membrane structure is not a requirement for the Con A effect. the results suggest that Con A inactivates the 5'-nucleotidase by a direct interaction with the enzyme and that this enzyme is a Con A receptor site on the surface of mammary cells.
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D002462:Cell Membrane / Q000201:enzymology; D003840:Deoxycholic Acid / Q000494:pharmacology; D003864:Depression, Chemical; D003902:Detergents / Q000494:pharmacology; D005260:Female; D005700:Galactosyltransferases / Q000378:metabolism; D008321:Mammary Glands, Animal / Q000201:enzymology*; D008766:Methylmannosides / Q000494:pharmacology; D009708:Nucleotidases / Q000378:metabolism*; D011092:Polyethylene Glycols / Q000494:pharmacology; D051381:Rats
chemical_list: D003902:Detergents; D008766:Methylmannosides; D003840:Deoxycholic Acid; D011092:Polyethylene Glycols; D005700:Galactosyltransferases; D009708:Nucleotidases; D000469:Alkaline Phosphatase; D000251:Adenosine Triphosphatases