Microarray Strategies for Exploring Bacterial Surface Glycans and Their Interactions With Glycan-Binding Proteins

Abstract

Bacterial surfaces are decorated with distinct carbohydrate structures that may substantially differ among species and strains. These structures can be recognized by a variety of glycan-binding proteins, playing an important role in the bacteria cross-talk with the host and invading bacteriophages, and also in the formation of bacterial microcolonies and biofilms. In recent years, different microarray approaches for exploring bacterial surface glycans and their recognition by proteins have been developed. A main advantage of the microarray format is the inherent miniaturization of the method, which allows sensitive and high-throughput analyses with very small amounts of sample. Antibody and lectin microarrays have been used for examining bacterial glycosignatures, enabling bacteria identification and differentiation among strains. In addition, microarrays incorporating bacterial carbohydrate structures have served to evaluate their recognition by diverse host/phage/bacterial glycan-binding proteins, such as lectins, effectors of the immune system, or bacterial and phagic cell wall lysins, and to identify antigenic determinants for vaccine development. The list of samples printed in the arrays includes polysaccharides, lipopoly/lipooligosaccharides, (lipo)teichoic acids, and peptidoglycans, as well as sequence-defined oligosaccharide fragments. Moreover, microarrays of cell wall fragments and entire bacterial cells have been developed, which also allow to study bacterial glycosylation patterns. In this review, examples of the different microarray platforms and applications are presented with a view to give the current state-of-the-art and future prospects in this field.

Glycans in Virus-Host Interactions: A Structural Perspective

“…We highlight the potential for a screen searching for novel chimeric topological mAbs, via grafting of known glycan-binding CDRs onto the 2G12 scaffold or by induction of domain exchange via mutation of the cross-over residues. In particular, anti-Bacterial glycan-targeting mAbs which tend to have desirable qualities—flexible recognition of multiple species due to targeting of “minimal” glycoepitopes Rollenske et al (2018) —as well as diagnostic microarrays, which have already characterized sets of mAbs and their glycan specificities Campanero-Rhodes et al (2020) , may serve as logical starting points. As described earlier, computational methods to predict glycan cluster topology and variability would greatly enhance these efforts.…”

Aberrant glycosylation patterns on cancer cells: Therapeutic opportunities for glycodendrimers/metallodendrimers oncology

“…These peculiarities have opened their use as targeting opportunities for cancer vaccines. Moreover, the specific binding of three members of the galectin family, that is, galectin 3, a chimera type, and galectins 4 and 8, having tandem-repeat-types ( Figure 7), has identified some of the above-discussed TACAs as ligands (Campanero-Rhodes, Sa Palma, Menéndez, & Solís, 2020). Galectins, which bind β-D-galactopyranoside residues, are widely expressed in epithelial and immune cells.…”

“…This section will highlight the pioneering work from the main author's laboratory together with recent investigations published since then. Of particular interest in this regard is the finding that some human sera of healthy individuals already contained antibodies against the TACAs, as determined using modern glycan microarrays (Campanero-Rhodes et al, 2020). This suggested that people have been somehow previously exposed to these biomarkers further highlighting the immunogenicity of glycans and their potential utility to generate immunotherapeutic agents.…”

Recent progress in chemical synthesis of bacterial surface glycans

“…bacterial surface glycans, peptidoglycans, glycoproteins for some species, and capsular polysaccharides (CPSs) are presented by both Gram-positive and Gram-negative bacteria. The former also contain lipoteichoic acids (LTAs) and wall teichoic acids (WTAs) while the latter contain lipopolysaccharides (LPSs) or lipooligosaccharides (LOSs) [1]. Some bacteria also produce exopolysaccharides (EPSs) which are a part of biofilm [2].…”