Synthesis of FRET Probes for the Determination of Activity of a Catalytic Monoclonal Antibody

PS2 Poster session 2 Even numbers
Location (hall): 
Start/end time: 
Tuesday, July 2, 2019 - 15:45 to 17:15
Conor Joseph

Conor Joseph Crawford1, Lorenzo Guazzelli1,2, Arturo Casadevall3, Stefan Oscarson1

1University College Dublin, Dublin, Ireland, 2Università di Pisa, Pisa, Italy, 3John Hopkins University, Baltimore, USA

18B7 a monoclonal antibody against the glucuronoxylomannan (GXM), a major component of the polysaccharide capsule that surrounds Cryptococcus neoformans, has been identified to have catalytic activity.1 18B7 is able to hydrolyse GXM oligosaccharides, providing the first example of a naturally occurring catalytic antibody for polysaccharides. To better understand the kinetic activity, synthesis of oligosaccharide Förster Resonance Energy Transfer (FRET) probes has been undertaken. Details of the synthesis and the problems encountered towards these oligosaccharide FRET will be presented.

Figure 1. Schematic representation of oligosaccharide FRET probe. FRET uses a fluorophore and quencher pair. When in the same molecule the fluorophore is ‘quenched’ by the quencher. However when the probe is hydrolysed the fluorophore returns to its original fluorescence. This change in fluorescence allows for kinetic activity to be calculated.

  1. Bowen, A. et al. Journal of Biological Chemistry. 2016, 292, 417-434.