Project Title: Life in the freezer: the role of dimethylsulfoniopropionate (DMSP) in the physiological and biochemical adaptations of Antarctic microalgae
Email Contact: Cristin.E.Sheehan@student.uts.edu.au
Parts of the Antarctic are warming at a rate far in excess of the rest of the planet, this very real and present threat to Antarctic life – life adapted to living in a freezer- is exacerbated by high levels of ultraviolet radiation (UVR) in the spring. During periods of increased environmental stress, marine microalgae have shown an increased accumulation of reactive oxygen species (ROS) leading to oxidative stress within the algal cells photosystem, which can cause a suppression in cell growth or induce cell death. Microalgal cells have mechanisms to protect themselves from the damaging effects of ROS, such as initiating non-photochemical quenching processes and the use of antioxidants. Recent studies have suggested that algal secondary metabolite dimethylsulfionopropionate (DMSP), and its breakdown products, may act as an effective antioxidant quenching ROS.
This project will investigate the physiological and biochemical responses to light and UVR in Antarctic marine microalgae, looking at oxidative stress, antioxidant activity and the synthesis and utilisation of dimethylsulfionopropionate (DMSP) and its degradation products (DMS and DMSO). Using fluorometry and advanced imaging tools in conjunction with biochemical analyses this project aims to gain an understanding of the links between physiological stress, ROS production and DMSP synthesis. This study will deliver new information on the mechanisms for stress management that underpin the evolutionary adaptation of these organisms to their unique environment.