Rapid screening for specific glycosylation and pathogen interactions on a 78 species avian egg white glycoprotein microarray

There is an urgent need for discovery of novel antimicrobials and carbohydrate-based anti-adhesive strategies are desirable as they may not promote resistance. Discovery of novel anti-adhesive molecules from natural product libraries will require the use of a high throughput screening platform. Avian egg white (EW) provides nutrition for the embryo and protects against infection, with glycosylation responsible for binding certain pathogens. In this study, a microarray platform of 78 species of avian EWs was developed and profiled for glycosylation using a lectin panel with a wide range of carbohydrate specificities. The dominating linkages of sialic acid in EWs were determined for the first time using the lectins MAA and SNA-I. EW glycosylation similarity among the different orders of birds did not strictly depend on phylogenetic relationship. The interactions of five strains of bacterial pathogens, including Escherichia coli , Staphylococcus aureus and Vibrio cholera , identified a number of EWs as potential anti-adhesives, with some as strain- or species-specific. Of the two bacterial toxins examined, shiga-like toxin 1 subunit B bound to ten EWs with similar glycosylation more intensely than pigeon EW. This study provides a unique platform for high throughput screening of natural products for specific glycosylation and pathogen interactions. This platform may provide a useful platform in the future for discovery of anti-adhesives targeted for strain and species specificity.