Scientists from the Australian National University took part in the study along with counterparts from research institutions in Italy, France and the UK to support London's Imperial College which played the lead role.
In a statement, the ANU said cyanobacteria were able to survive in inhospitable climes with little light; thus, studying them could help scientists better understand photosynthesis, the process which plants and other organisms use to make and store energy and produce oxygen.
ANU Emeritus Professor Elmars Krausz said cyanobacteria could be used to colonise Mars and other planets, where they would, presumably, produce oxygen and create a biosphere.
“Photosynthesis could theoretically be harnessed with these types of organisms to create air for humans to breathe on Mars. Low-light adapted organisms, such as the cyanobacteria we’ve been studying, can grow under rocks and potentially survive the harsh conditions on the red planet,” he added.
Jennifer Morton at work in the research lab.
The ANU said that some kinds of cyanobacteria would thrive in Antarctica and the Mojave Desert and even on the outside of the International Space Station.
Jennifer Morton, a doctoral scholar at the ANU Research School of Chemistry and a co-author of the paper, said: “Chlorophyll adapted to absorb visible light is very important in photosynthesis for most plants, but our research identifies the so-called ‘red’ chlorophylls as critical components in photosynthesis in low-light conditions."
She said a study of the red chlorophylls would also provide leads as to where one should look for life on other planets.
“Searching for the signature fluorescence from these pigments could help identify extra-terrestrial life,” she said.
A key discovery was identifying a significantly different mechanism of photosynthesis that enhanced the understanding of the process, more broadly, Morton said.
“This work redefines the minimum energy needed in light to drive photosynthesis. This type of photosynthesis may well be happening in your garden, under a rock.”
She said an organism that had adapted to low light would be killed by exposure to sunshine.
“All photosynthetic organisms, such as coral reefs, suffer severe environmental stresses from high temperatures, high light levels and ultraviolet light, so this research helps scientists to better understand these limits,” she said.
The ANU researchers used an optical spectrometer system to analyse the role of red chlorophylls in photosynthesis and are using computer modelling to further understand the role played by these chlorophylls.
Photos: courtesy ANU