Capturing sialyl-glycan via a site-selective installation of boronic acid repertoire in peptides

Abstract

The broad spectrum of covalent binding modes and interactions has ‘magically’ popularized the submission of boronic acid-mediated chemistry into chemical biology and medicinal chemistry. Since borono peptide-based applications are emerging, simplistic methods for direct late-stage and site-selective installation of a versatile boronic acid (BA) repertoire onto peptides are desirable, given the limited chemical strategies. Here, we investigate the efficacy of thiol-ene click chemistry for installing functionally versatile BA derivatives on numerous bioactive, native peptides in a site-selective manner. The work emphasizes adaptable applications with BA-modified peptides, such as cyclization, conjugation, and biomolecule recognition. To this end, the click method enables us to nurture the sialyl-glycans binding aptitude of various BA-modified WGA peptides concurrently. The consequence reveals that the WGA peptide (in silico derived from wheat germ agglutinin), which shows a considerably low affinity to sialic acid, turns into a potent and selective binder in the attendance of a suitable BA probe to it. The synergistic recognition intensified the binding and profiling of sialyl-glycan on cancer cell lines compared with widely used lectin, Sambucus nigra.