The specific objectives are: 

i. to identify and characterise candidate bacterial mucin-targeting metallopeptidases with ability to differentiate mucin-type O-glycosylation and recognise distinct O-glycan structures; 

ii. to map the molecular determinants of O-glycan and peptide recognition for application or modulation of enzyme specificity and selectivity in O-glycoproteomics and O-glycomics; 

iii. to evaluate the enzyme toolbox for analysis of cancer-associated glycoproteins in gastrointestinal cancer cell models. 

GlycOSELECT gathers an interdisciplinary team in molecular biology, protein biochemistry, structural biology, chemoenzymatic synthesis, technologies in functional glycomics, glycoproteomics and cancer cell biology.

The innovation underlying the proposed research plan relies on the expertise of the PI and the team in designing glycan microarray strategies that will target the screening of not only a wide diversity of bacterial proteins but also a unique collection of mucin-type glycoproteins with innumerable O-glycan structures.

This approach will direct research for the detailed characterization at molecular level of the specificity of the bacterial metallopeptidases and their peptide sequence selectivity for the structure-based rational design of bacterial proteins to apply in cancer research.

A predicted outcome is to obtain proof-of-concept data to exploit the protein toolbox for molecular analysis of cancer-associated glycoproteins derived from clinical samples using site-specific extraction of O-linked glycopeptides. This is crucial to understand their function in a disease setting. We anticipate that the protein tools we will develop will enable the discovery of additional altered mucin glycosylation patterns that contribute to disease and reveal specific mucin-type O-glycosylation biomarkers that correlate with clinical outcomes for cancer diagnosis and therapy. The potential of identifying the O-glycan selectivity of the novel enzymes, with translation towards analysis of clinical samples and human epithelial tissues, will also advance the development of the human epithelial mucin/O-glycome resources for recognition studies in disease.