Synthesis and characterization of soluble concanavalin A oligomer.
Concanavalin A, (Con A, MW 26,500/monomer unit) was crosslinked with glutaraldehyde to form soluble, high-molecular-weight (larger than MW 300,000) Con A Oligomers. After filtration to remove insoluble and low-molecular-weight portions (below 300,000 daltons), the size and molecular-weight distribution were characterized by laser light scattering and gel-filtration chromatography. The molecular-size determined by laser light scattering ranged from 870 to 4070 A, while the molecular weight determined by gel chromatography ranged from 6 x 10(5) to higher than 2 x 10(6) daltons. The affinity and kinetics of Con A oligomer binding to polysaccharide (glycogen) were evaluated by precipitation test and turbidity development, respectively. The binding with glycogen was strongest at neutral pH and showed similar activity to unmodified Con A molecules. The binding constants of alpha-D-glucose and succinyl-aminophenyl alpha-D glucopyranoside-insulin to Con A oligomer were 1.0 x 10(3)M(-1) and 4.5 x 10(4)M(-1), respectively and the binding capacity of the oligomer was nearly 85% to 95% of monomeric Con A. The complexes of saccharides and soluble Con A oligomer were stable for at least 7 days.
Pai
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Department of Pharmacrautical Chemistry, Center for Controlled Chemical Delivery, University of Utah, 421 Wakara Way, Suite 318, Salt Lake City, UT 84108, USA.
Jacobs
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Bae
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Kim
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