Lectin-mediated adhesion: Testing of tailor-made cellulose derivatives with ConA and live E. coli bacteria

Due to the high exigence for treatment of bacterial infections, anti-adhesion therapy has emerged as an alternative method in an era of antibiotic resistance. Here, we have conjugated azido-functionalized cellulose with specific carbohydrate ligands (mannose and glucose, respectively) via copper-catalyzed azide-alkyne click chemistry (CuAAC) resulting in homo- and hetero-glycosylated cellulose derivatives with a DS > 0.9. The new materials, Cellul^Man and Cellul^ManGlc, were evaluated as potential anti-adhesive reagents with type 1-fimbriated E. coli bacteria and additionally with the plant lectin Concanavalin A (ConA). We have determined the adhesion properties of the new glycopolymers as well as their agglutination behavior in an in-depth study combining two- and three-dimensional assays. The tested synthetic glycopolymers differ in their biological behavior as lectin ligands depending on the respective glycodecoration. In particular, Cellul^Man shows a remarkably low minimal effective concentration c_min ≤ 2 pg/mL as adhesive material with E. coli. Overall, the assays demonstrate that glyco-modified cellulose serves as an excellent antiadhesive as well as adhesive surface material for both type 1 fimbriated E. coli and ConA, being superior to natural polysaccharides.