TY - JOUR
T1 - Nonstatistical binding of a protein to clustered carbohydrates
AU - Horan, Nina
AU - Yan, Lin
AU - Isobe, Hiroyuki
AU - Whitesides, George M.
AU - Kahne, Daniel
PY - 1999/10/12
Y1 - 1999/10/12
N2 - Carbohydrate-derivatized self-assembled monolayers (SAMs) are used as a model system to address issues involving cell-surface carbohydrate-protein interactions. Here we examine the influence of carbohydrate surface density on protein-binding avidity. We show that the binding selectivity of Bauhinia purpurea lectin switches from one carbohydrate ligand to another as the surface density of the carbohydrate ligands increases from values of χ(sugar) ≃ 0.1-1.0. Polyvalent binding is possible at all surface densities investigated; hence, the switch in selectivity is not due simply to the achievement of a critical density that permits polyvalent contacts. Instead, secondary interactions at high surface densities promote a switch in carbohydrate-binding selectivity. These findings may have implications for how changes in the composition and the density of cell-surface carbohydrates influence biological recognition processes and regulatory pathways.
AB - Carbohydrate-derivatized self-assembled monolayers (SAMs) are used as a model system to address issues involving cell-surface carbohydrate-protein interactions. Here we examine the influence of carbohydrate surface density on protein-binding avidity. We show that the binding selectivity of Bauhinia purpurea lectin switches from one carbohydrate ligand to another as the surface density of the carbohydrate ligands increases from values of χ(sugar) ≃ 0.1-1.0. Polyvalent binding is possible at all surface densities investigated; hence, the switch in selectivity is not due simply to the achievement of a critical density that permits polyvalent contacts. Instead, secondary interactions at high surface densities promote a switch in carbohydrate-binding selectivity. These findings may have implications for how changes in the composition and the density of cell-surface carbohydrates influence biological recognition processes and regulatory pathways.
UR - http://www.scopus.com/inward/record.url?scp=0032718387&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0032718387&partnerID=8YFLogxK
U2 - 10.1073/pnas.96.21.11782
DO - 10.1073/pnas.96.21.11782
M3 - Article
C2 - 10518527
AN - SCOPUS:0032718387
VL - 96
SP - 11782
EP - 11786
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
SN - 0027-8424
IS - 21
ER -