Structural studies of bio-molecules and lipid assemblies using polarized light spectroscopy

Licentiate thesis, 2011

The focus of the research presented in this thesis is structural studies of biological macromolecules using Linear Dichroism (LD) spectroscopy. The first part covers the flow alignment and structure of DMPC/DHPC phospholipid aggregates. By using membrane probes, we investigate the orientation behaviour of the lipid phase over a broad range of conditions such as temperature, hydration and shear gradient. The biophysical application of DMPC/DHPC membrane systems for structural studies of membrane bound proteins is demonstrated for the Cytochrome C protein. Second part of this thesis concerns the intercalation of a bidppz-bridged binuclear ruthenium complex (ΔΔ-P) into imperfectly paired DNA. We find that incorporation of an unpaired region in an oligonucleotide duplex strongly reduces the activation barrier, suggesting that such a structure may be proposed as a model for the DNA intercalation transition state.