Assoc Prof Duncan McGillivray
Surface Chemistry and Materials
Duncan's research involves looking at the surface structures of biological systems using surface sensitive methods, particularly neutron and X-ray scattering.
The recent commissioning of the OPAL research nuclear reactor in Sydney, and the opening of the Australian Synchrotron X-ray source in Melbourne, provide world-class facilities within easy reach of Auckland. Through measurements performed at these facilities the behaviour of surfaces – and in particular biological membranes – can be studied in detail.
Oxidative stress on cellular membranes
Cellular membranes act as both a support and a gateway for biological cells, and achieve their multiple purposes through their complex compositions including lipids, proteins and sugars. When these membranes are attacked by oxidative stresses (e.g., free radicals) their behaviour changes, and this has been linked to a number of diseases including heart disease, Alzheimer’s and Parkinson’s. By using a simpler model membrane the relationships between the membrane damage, cellular defences and disease pathologies can be investigated. This work is also related to a study on antioxidants in foods with Prof Melton of Food Science.
Membrane-incorporated membrane proteins
Membrane proteins – those that function through interactions with cellular membranes – are some of the most significant functional proteins in biology, but are also some of the least well understood. The complex and highly asymmetric environment in which these proteins operate makes them challenging targets for study. Using the same model membrane system on a solid support, as above, functional membrane proteins can be incorporated and studied in situ. This approach has already been used in looking at the bacterial toxin a-hemolysin, and will be extended to other related membrane proteins (in collaboration with A/Prof. Mitra, SBS) and synthetic biological materials (with Prof. Middelberg, University of Queensland).
Functional foods are those that provide a health benefit beyond simple nutrition – for example cholesterol-lowering margarines. Designing functional foods relies on an understanding of their physical properties and interactions with digestive systems, which can be determined in part from their structural characteristics. With Dr Quek of Food Science work on emulsions on cholesterol-lowering food additives is underway.
The development of sensors for biological analytes, such as DNA, is an area of much research interest. In collaboration with Dr Travas-Sejdic and Prof Williams the structural response of biosensor-type materials to analytes can be studied in response to environmental conditions.