A Workflow to Analyze ETHcD Mass Spectrometry Data for Studying HIV gp120 Glycosylation

Abstract

The great heterogeneity of HIV populations and richness of surface glycan clouds makes it difficult to locate a conserved and exposed protein epitope as an effective vaccine target. However, more than 80% new infections result from single transmitted founder (T/F) viruses. We set out to design a workflow to study the traits of T/Fs that allow for their superior infectivity, specifically, the glycosylation patterns of gp120, a subunit of HIV envelope protein responsible for binding to host cell receptors. Our main research methods include Western blot and mass spectrometry. Our current understanding of the mass spectrometry data indicates that our T/F and chronic HIV strains have differential distributions of glycan density at several key N-sites throughout the gp120 peptide backbones, which may be related to the differential transmission fitness of the two strains and potentially used as novel glycopeptide-based HIV vaccine targets