Synthesis and evaluation of affinity adsorbents for glycoproteins: an artificial lectin

摘要: Abstract A combination of rational design based on mimicking natural protein–carbohydrate interactions and solid-phase combinatorial chemistry has led to the identification an affinity ligand which displays selectivity for mannose moiety glycoproteins. The ligand, denoted 18/18 comprising a triazine scaffold bis-substituted with 5-aminoindan, been synthesised in solution, characterised by TLC, 1H-NMR MS. When immobilised amine-derivatised agarose at concentrations >24 μmol/g moist weight gel, selectively binds glucose oxidase. adsorbed enzyme was quantitatively eluted 0.5 M α- d -methyl-mannoside lesser extent equivalent glucoside. An investigation comparative retention times saccharidic solutes showed that significant retardation observed -mannose, mannobiose mannan, little or no evidence selective other saccharides, exception l -fucose. Interestingly, -fucose -mannose share identical configuration hydroxyl groups C-2, C-3 C-4. Analysis Scatchard plots from partition equilibrium studies interaction oxidase p-nitrophenyl-glycosides -glucose, -galactose establish constants (KAX) enzyme, glycosides mannose, fucose, p-nitrophenyl-galactoside are 4.3×105 M−1, 1.9×104 M−1 1.2×104 respectively. solution confirm involvement group C-2 position. Molecular modelling suggests formation four hydrogen bonds between positions C-4 bridging ring nitrogen atoms scaffold, aromatic stacking second against carbohydrate face. greater specificity than galactose parallels exhibited concanavalin A.