There is much interest in understanding how proteins are able to recognise and target specific biological membranes. For example, sea anemones produce a range of cytolysins which are cytotoxic peptides potentially lethal to vertebrates. An important class of these cytolysins are the actinoporins.  Actinoporins, such as the toxin EqtII from Actinia equina L, bind to membranes and then, depending on the composition of the membranes in the target cells, cooperatively assemble into transmembrane pores. 

To shed more light on this system, Dr David Poger and Professor Alan Mark of the Molecular Dynamics group at UQ are using atomistic molecular dynamics simulations to study in detail the interaction between EqtII and various models of biological membranes and for comparison with the available experimental data.  By simulating the interaction of EqtII with membranes containing various concentrations of sphingomyeline they hope to

1. observe the toxin in the initial stages of binding and assembly into a pore
2. determine the role of sphingomyeline in binding and pore formation
3. determine the role of specific amino acids in binding.

The Molecular Dynamics group at relatively new to UQ. The group focuses on predicting the macroscopic (experimentally observable) properties of biomolecular systems such as proteins, nucleic acids and lipid aggregates, in terms of the interactions between atoms. They primarily use and contribute to the molecular dynamics simulation packages GROMACS and GROMOS.

Participants

Dr David Poger, Professor Alan E. Mark
Molecular Dynamics Group, School of Molecular and Microbial Sciences, UQ