Final Report Summary - GLYCOTUP (Novel Chemical Probes for Tuberculosis Diagnosis and Treatment)
1. Development of a dehydrative glycosylation protocol for the preparation of symmetrical 2,2'-dideoxy-2,2'-dihalo-α,α-trehalose analogues from readily available precursors.
2. Expansion of the above protocol for the preparation of unsymmetrical 2-deoxy-2-halo-α,α-trehalose analogues
3. Development of an acid-catalyzed addition of FDG to glycals from readily available precursors that allow for 18F incorporation.
4. Confirmation that unsymmetrical 2,2'-dideoxy-2-fluoro-trehalose and related derivatives are efficiently processed by M. tuberculosis mycolyltransesterase enzyme ag85C in vitro.
5. Confirmation that M. tuberculosis culture in vitro takes up decent amounts of single label 14C-labeled trehalose and derivatives.
6. Confirmation that M. tuberculosis can be selectively labelled within macrophages with a fluorescein-containing Tre probe.
7. Synthesis of carbohydrates with different configuration (gluco, galacto, manno), C-2 group (F, NHAc) and anomeric linkage (S, Se) for OtsA-mediated preparation of unsymmetrical 2-deoxy-2-substituted-α,α-trehalose and also for the development of protein engineering methods for studing the mechanistic trapping of Mtb-associated carbohydrate-processing enzymes (antigen 85 proteins).
8. Development of a combined chemical tagging method followed by Endo-A catalyzed elongation allows access to homogeneous, elaborated glycoproteins. A survey of different linkages and sugars (including F-sugars) demonstrated not only that unnatural linkages can be tolerated but they can provide insight into the scope of Endo-A transglycosylation activity.
9. Exploring new methods for the preparation of dehydroalanine as a handle for the development of Mtb-associated protein modification methods.
10. Synthesis of SeS-linked homogeneous glycoproteins as a privilege tag for X-ray analysis of Mtb-associated proteins.
11. Development of a chemical site-selective method for the incorporation of [18F]fluorine into proteins.
Contact details:
Prof. Benjamin G. Davis and Dr. Omar Boutureira
Chemistry Research Laboratory
Department of Chemistry, University of Oxford, 12 Mansfield Road,
Oxford OX1 3TA, UK
Ben.Davis@chem.ox.ac.uk
Omar.Boutureira@chem.ox.ac.uk