Synthesis of a Library of Fucosylated Glycoclusters and Determination of their Binding toward Pseudomonas aeruginosa Lectin B (PA-IIL) Using a DNA-Based Carbohydrate Microarray

Abstract

Pseudomonas aeruginosa (PA) is a Gram negative opportunistic pathogen and is the major pathogen encounter in the cystic fibrosis (CF) lung airways. It often leads to chronic respiratory infection despite aggressive antibiotic therapy due to the emergence of resistant strains and to the formation of biofilm. The lectin PA-IIL (LecB) is a fucose-specific lectin from PA suspected to be involved in host recognition/adhesion and in biofilm formation. Thus, it can be foreseen as a potential therapeutic target. Herein, 16 fucosylated glycoclusters with antenna-like, linear, or crown-like spatial arrangements were synthesized using a combination of DNA solid-phase synthesis and alkyne azide 1,3-dipolar cycloaddition (CuAAC). Their binding properties toward PA-IIL were then evaluated based on DNA directed immobilization (DDI) carbohydrate microarray. Our results suggested that the antenna-like scaffold was preferred to linear or crown-like glycoclusters. Among the crown-like carbohydrate centered fucosylated glycoclusters, mannose-based core was better than glucose- and galactose-based ones. The influence of the linker arm was also evaluated, and long linkers between fucoses and the core led to a slight better binding than the short ones.

Importance of topology for glycocluster binding to Pseudomonas aeruginosa and Burkholderia ambifaria bacterial lectins

“…We have previously reported the syntheses of glycoclusters with a hexose-platform exhibiting either galactose [11][12][13] or fucose 12,14 epitopes for interactions with LecA and LecB respectively. To gain more insight into the effect of topology and valency on the affinity of the corresponding glycoclusters toward LecA and LecB, we have designed two new families of glycoclusters.…”

Mannose-centered aromatic galactoclusters inhibit the biofilm formation of Pseudomonas aeruginosa

“…The methodologies for K d and IC 50 values determination have been previously reported. 40,55,56 K d determination by glycoarray. Galactocluster oligonucleotide conjugates 1 DNA to 3 DNA (1 μM final concentration) were diluted in PBS-0.02% Tween 20 -2% BSA solution.…”

Effects of the Surface Densities of Glycoclusters on the Determination of Their IC50 and Kd Value Determination by Using a Microarray

“…[16][17][18] Ta rgeting of lectins of PA with glycoclusters appears to be an ew therapeutic option. [19][20][21][22][23][24][25][26] The "cluster glycoside effect", combined with an appropriate topology of the glycocluster,would allow aperfect match between its carbohydratesa nd the CDRs of the lectin. Furthermore, the stabilization of such al ectin·glycocluster complex, thankst oa dditional interactions, should lead to the identification of the best candidates with which to target lectins of PA. [27][28][29] However, multivalent interactions are highly dependento nm atching between the glycocluster and the lectin topologies, and also to acertain extent on the number of carbohydrate residues and on the chemicaln ature of the linkers between the carbohydrate residues and the cores of the clusters.…”