RESEARCH

Metabolic basis of microbial persistence

Bacteria are able to dominate practically all ecosystems due to their unprecedented ability to survive environmental deprivation and change. To achieve this, environmental and pathogenic bacteria alike enter stress-resistant dormant states in response to environmental downturns. We are investigating the metabolic mechanisms that allow them to stay energised and resist stresses in their dormant states.

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For example, our research has shown that a wide range of heterotrophic bacteria scavenge atmospheric trace gases to survive carbon deprivation. Likewise, we have provided evidence that fermentation is a broadly conserved mechanism of energy conservation, even among aerobes. We are now exploring the molecular basis and macroscopic significance of such processes through an interdisciplinary approach.

Fundamental research with broad implications

Understanding the metabolism of microorganisms in their dormant state has broad implications. For example, soil bacteria in their dormant state mediate key steps in the biogeochemical cycles of climate-relevant atmospheric gases such as methane and hydrogen. Among pathogens, Mycobacterium tuberculosis depends on redox and energy homeostasis to resist drug treatment in its dormant state. We investigate microbial persistence in the context of the following core themes — click on each image to learn more:

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An interdisciplinary approach

The Greening Lab takes an interdisciplinary approach in order to understand biological processes at all levels of organisation: from enzymatic mechanisms to ecosystem importance. The benefits of an integrative microbiology approach are reflected by our work demonstrating the environmental ubiquity of microbial H2 metabolism and the medical importance of mycobacterial F420.

To achieve this, we employ a versatile suite of bacteriology, molecular biology, microbial ecology, protein biochemistry, and analytical chemistry approaches. We collaborate with world experts in areas where we are non-experts, including A/Prof Perran Cook (biogeochemistry), A/Prof Colin Jackson (structural biology), and Prof Gregory Cook (PC3 experiments). By combining internal and collaborative research, we can understand microbial processes at all levels of cellular organisation.