Optimising light-driven microalgae cell factories: Biochemical studies of Photosystem II mutants and their light harvesting systems

The global transition to reach Net Zero carbon dioxide emissions by 2050 is forecast to require US$144 trillion (or $5.5 trillion annually to 2050) of investment, highlighting an extraordinary opportunity to develop renewable technologies.

The sun is by far the largest renewable energy resource available to us, and every 2 hrs provides Earth with more energy than is required to power our entire global economy for a year.

Oxygenic photosynthetic organisms including plants, algae and cyanobacteria (and the intricate photosynthetic machinery within them) form the biological interface between the sun and our biosphere. Over 3 billion years, these intricate photosynthetic interfaces have evolved to capture this solar energy and CO2 to generate oxygen and biomass that provide the food, fuel, biomaterials, and clean water that support aerobic life on Earth.

The first step of photosynthesis and all light-driven biotechnologies is light capture by the Light Harvesting Complex (LHC) proteins associated with Photosystems I and II. This PhD project will focus on biochemically and functionally defining key LHC trimers and ~ 1MDa photosynthetic supercomplexes. This work supports the structure-guided design of next-generation high-efficiency CRISPR-engineered cell lines for light-driven biotechnology applications.

The successful PhD candidate will be part of a strong multi-disciplinary team in the Centre for Solar Biotechnology (CSB; 30 international teams, ~35 industry partners to date) within the Institute for Molecular Bioscience (IMB) at the University of Queensland (UQ). The IMB is one of Australia’s premier life sciences institutes and ranks highly internationally. UQ regularly ranks in the top 1% (top 50) universities internationally.

The CSB and our industry partners are focused on developing advanced light-driven biotechnologies based on single cell green algae that tap into this huge solar energy resource and use it to drive the production of a broad range of products from high-value recombinant proteins through to cost-competitive renewable fuels. The IMB has excellent protein biochemistry facilities (protein purification, cryo-electron microscopy and mass spectrometry) as well as powerful robotic systems (to screen for high-efficiency cell lines) to support this work.

The project will involve microalgal cell culture, light microscopy, purification of photosystem complexes by sucrose density gradient centrifugation and FPLC, biochemical and biophysical analyses of these complexes, negative stain and cryo-electron microscopy. They will also have the opportunity to use the state-of-the-art cryo-EM facilities to collect atomic resolution images for single particle analysis.

The IMB is located at the beautiful sub-tropical St Lucia Campus of the University of Queensland and provides easy access to the Brisbane CBD, Stradbroke Island, the Sunshine Coast, Gold Cost, Gold Coast hinterland and flights to the Great Barrier Reef via Brisbane Airport.

The successful PhD candidate will be part of a strong multi-disciplinary team in the Centre for Solar Biotechnology (CSB; 30 international teams, ~35 industry partners to date) within the Institute for Molecular Bioscience (IMB) at the University of Queensland (UQ). The IMB is one of Australia’s premier life sciences institutes and ranks highly internationally. UQ regularly ranks in the top 1% (top 50) universities internationally.