Unraveling the Glycosylation Machinery of Bothrops jararaca Snake Through Multiomics and Structural In Silico Analyses.

Glycosylation is a ubiquitous post-translational modification (PTM) that influences folding, stability, and function of proteins. In eukaryotes, N-glycosylation corresponds to the linkage to asparagine (Asn), while O-glycosylation involves the linkage to serine (Ser) or threonine (Thr). Although glycosylation is one of the main PTMs of viperid snake venoms, the enzymatic machinery associated with toxin glycosylation remains poorly characterized in venomous organisms. To fill in this gap, we performed multiomics and structural in silico analyses of publicly available experimental genomic, transcriptomic, and proteomic datasets, combined with structural modeling, to investigate the glycosylation pathway of the medically important snake B. jararaca. The multiomics analysis suggested that the glycosylation machinery is coupled to the venom production cycle and influenced by sex-specific differences, underscoring the glycosylation heterogeneity between female and male specimens. In addition, comparative transcriptomics analysis highlighted different expression patterns of glycosyltransferases and glycosidases in different tissues. Moreover, structural analysis of the predicted oligosaccharyltransferases complexes and glycosylated toxins provided insights into the glycosylation pathway in the venom gland. Collectively, our study advances the understanding of the synthesis and processing of toxins and sheds light into the conservation and variability of the glycosylation machinery.