Determination of lectin-sugar dissociation constants by agarose affinity electrophoresis.
Agarose crossed affinity electrophoresis (aff-EP) was employed for the determination of lectin-sugar dissociation constants (Ki). In the first dimension of the aff-EP increasing amounts of sugar (alpha-methyl-D-mannoside) were added to a given concentration of lectin (concanavalin A). Then the electrophoresis was run with alpha 1-acid glycoprotein, alpha 1-antitrypsin and alpha-fetoprotein as markers of lectin-sugar interactions. Mathematical equations for determination of the mechanisms and constants of lectin-sugar-glycoprotein interactions were developed. The mean value of the concanavalin A-alpha-methyl-D-mannoside dissociation constant calculated according to the introduced equations was 0.28 mM. In this system it was also possible to determine lectin-glycoprotein dissociation constants (K). The observed influence of the sugar on lectin-glycoprotein binding might be due to hydrophobic interactions since the addition of nonionic detergent caused reversal of this phenomenon.
D002241:Carbohydrates / Q000032:analysis*; D003208:Concanavalin A; D004587:Electrophoresis, Agar Gel; D006801:Humans; D037102:Lectins / Q000032:analysis*; D009961:Orosomucoid / Q000032:analysis; D000515:alpha 1-Antitrypsin / Q000032:analysis; D000509:alpha-Fetoproteins / Q000032:analysis
D002241:Carbohydrates; D037102:Lectins; D009961:Orosomucoid; D000515:alpha 1-Antitrypsin; D000509:alpha-Fetoproteins; D003208:Concanavalin A