Neoglycoconjugates of Mannan with Bovine Serum Albumin and their Interaction with Lectin Concanavalin A

Mannan from Saccharomyces cerevisiae was modified by periodate oxidation to dialdehyde derivatives with different oxidation degree and Mw. The reactive mannans were subsequently bound to bovine serum albumin (BSA) forming mannan-BSA conjugates. These neoglycoproteins, containing 25—30 % w/w of the saccharide, Mw within the range 169—246 kDa, show dispersion (Mw/Mn) from 2.8 to 3.6. The interaction of mannan-BSA conjugates with Concanavalin A was studied. In comparison with the original mannan, only insignificant changes in the precipitation course of mannan-BSA conjugates with Concanavalin A were observed. The interaction of mannan- BSA conjugates with Concanavalin A was confirmed also by sorption experiments with lectin immobilized on bead cellulose matrix as well as by surface plasmon resonance method using a chip with surface modified by immobilized lectin. The determined dissociation constants of the modified mannans and their albumin conjugates interacting with Concanavalin A ranged between 10-6—10-8 M.