Presenter 1: Nicole Wheatley (PhD Student, Mark Group, SCMB)

Title: Structure refinement and validation of protein:ligand complexes, and its application to computational drug design

Abstract: Drug design is critically dependent on the accuracy of protein:ligand complexes. This is reflected by the exponential growth of the structures deposited within the Protein Data bank (PDB), of the more than 110 000 protein structures 20% contain a ligand bound within. While many regard structures solved using crystallographic techniques uncritically; errors in the protonation state, geometry, and binding pose of the ligands are difficult to identify based on standard X-ray refinement measures of quality (R-values).  As a consequence, a significant number of structures are either known to, or potentially have errors. The focus of my project is to test and develop potential approaches, based on the use of physically realistic molecular interaction functions, to detect and correct such errors in known structures.


Presenter 2: Ann Bui (Research Fellow, Bernhardt Group, AIBN)

Title: Calibration of optical tweezers for force microscopy

Abstract: Optical tweezers are an important tool in biophysics for their ability to noninvasively control microscopic particles, and perform quantitative force measurements in cellular environments. Quantitative force measurements require a calibration. Force calibration of optical tweezers for unknown environments is difficult as existing methods rely on detailed knowledge of the medium and the trapped particle's properties. I shall discuss the calibration methods used to determine the forces acting on chromosomes, the development of a method of absolute force calibration and how this can be used to measure non-optical forces like membrane forces and swimming forces. This leads to my current work which is considering non-equilibrium thermodynamics to determine membrane potentials, or force landscapes.



AIBN Seminar Room