Molecular Modelling of Mannan-Latching

Carbohydrate-Carbohydrate Interactions (CCI) are observed in many biological contexts such as cell-cell interactions and host-pathogen interaction. Although there is a considerable amount of evidence indicating that CCI mediates cell adhesion, cell signalling and cell recognition events, their specific role is mostly left to qualitative speculation/treatments. This is in part due to researchers having very little interest in carbohydrates for historical reasons, and in part due to the very weak self-association strength of CCI –thus posing a major research challenge for both experimentalists and theoreticians.

In this project we devise atomistic simulations of CCI using the CHARMM force field (and other carbohydrate  forcefield variants) to study the qualitative properties of CCI and their relation to glycobiology. In particular, we are interested in mannans (linear polysaccharides made up of mannose residues) and how they aid cell adhesion and cell recognition events.

Although the project is still in progress, we find that molecular dynamic simulations of CCI show very weak interaction strengths. We also find that in solution, glucose and mannose disaccharides, trisaccharides and tetrasaccharides do not form clusters and have a relatively short life-span of interactions.