About our lab
The Burns Lab is based at the University of New South Wales, Sydney, Australia. Our lab has long focused on blue skies or curiosity driven research. Our lab has a strong sustainability focus and actively addresses key UN Sustainable Development Goals, and also engages with and values Indigenous Knowledge in science. This page outlines some of our research interests and strengths.
Stromatolites and the origins of life
Stromatolites and microbial mats are model systems for studying the origins and evolution of life on our planet. They are geobiological structures composed of complex and diverse microbial communities. Biomarkers in ancient mats are evidence of life, and recent work has demonstrated these systems emerged as far back as 3.7 billion years. The key to understanding the past is to study the present, and living mats are excellent model systems to address fundamental evolutionary questions. We have access to unique field sites on the coast of Western Australia – in particular the World Heritage site of Shark Bay - and other locations around the world through our collaborators. We also work closely with the Department of Parks and Wildlife to ensure these unique ecosystems are carefully monitored in the face of threats such as climate change. In particular, the impact of extreme stressors on microbial communities and critical pathways in threatened mat systems are being assessed and critical to ascertain before any irreversible ecosystem tipping points are reached.
The study of microorganisms associated with these formations may also be applied to the search of extraterrestrial life, particularly with the discovery of unique bio-signatures. This work thus aligns well with the goals of the Australian Centre of Astrobiology and our collaborators at NASA. Our work provides new metagenome-based models into how biogeochemical cycles and adaptive responses may be partitioned in the microbial mats of Shark Bay, including the genetic basis for potential novel natural products. The traditional tree of life is also in flux, and new discoveries we are making in these systems of novel organisms and pathways is affording a dynamic and holistic view of these ecosystems and the complex network of processes occurring through space and time. In particular we are pursuing the role of ‘microbial dark matter’ in these systems including the enigmatic group of Asgard archaea. This research program is relevant to a wide range of areas including microbial evolution, geobiology, paleobiology, computational biology, and biotechnology.
Microbial communication in extreme environments – Archaea ‘join the conversation’
Halococcus hamelinensis: one of the archaea from which our lab has detected putative intercellular signals
Communication in the microbial environment often occurs over microspatial distances utilizing small signal molecules to facilitate changes in community gene expression that confer a competitive advantage. Cell signalling is a fundamental process that may have co-evolved with communities and environmental conditions on the early Earth. Without cell signalling, evolutionary pressures may have even resulted in the extinction rather than evolution of certain microbial groups. One of the biggest challenges in extremophile biology is understanding how and why some microbial functional groups are located where logically they would not be expected to survive, and tightly regulated communication may be key. Our work in this area has examined this phenomenon in a range of extremes including, salinity, temperature and pH, and for the first time describing this process in microbial mats.
While well characterised in bacteria, the process of signalling in archaea is also not well understood. Given the growing significance of archaea in both natural and anthropogenic settings, it is important to delineate how widespread this phenomenon of signalling is in this domain of life and the impact on both organisms involved and the environment. Our work has examined this phenomenon in a range of archaea we have in culture, including those surviving extreme heat, salinity, and pH. Efforts are also underway to identify potentially novel signal molecules produced by this domain. There are significant gaps in knowledge in the field of archaeal communication, with the exciting prospect of cross-domain talk that may be critical to ecosystem function. It is clear from the emerging directions in the field that archaea have well and truly ‘joined the conversation.’
Bioastronautics: The influence of microgravity on cellular function
The technological and scientific advancements in astronautics have enabled mankind’s ability to explore space. Astronauts are exposed to a series of environmental factors and one of them is the absence of gravity. Future planetary missions and construction, maintenance and use of space stations will be achieved in weightlessness. The altered gravity conditions of space can have serious detrimental effects on the health of astronauts. Understanding the cellular basis of this phenomenon could also lead to better medical treatments on Earth. The transition from terrestrial to a space environment is known to have an impact on human physiology and cause adaptive or pathological changes. Hence, understanding the effects of weightlessness/microgravity on human physiology will ensure the development of health and safety of astronauts. Life’s basic processes are conducted at the cellular level, and the effect of microgravity on a variety of cell types haven been analysed in this research program.
This work is led by a former PhD student from the Burns lab, Dr Elizabeth Blaber, who currently works for NASA. Through collaborators at NASA, we had the opportunity to fly samples on the last two space shuttle missions and compared to ground controls. With the focus on stem cells, results indicated that mechanical unloading of stem cells in microgravity inhibited their differentiation and preserves stemness, possibly providing a cellular mechanistic basis for the inhibition of tissue regeneration in space and in disuse conditions on earth. The impact of this work was highlighted by appearing on the cover of the journal Stem Cells and Development in 2015.