In a paper just published in the journal Proceedings of the National Academy of Sciences (PNAS), Professor Greg Cook and colleagues have demonstrated for the first time that acidobacteria, the second most dominant bacteria in global soils, rely on hydrogen gas for survival.
It is well-established that the majority of bacteria in soil ecosystems live in dormant states due to nutrient deprivation, but the metabolic strategies that enable their survival had not yet been shown.
The researchers took an extreme approach to resolving this enigma. They studied a strain of acidobacteria named Pyrinomonas methylaliphatogenes that was cultivated from heated and acidic geothermal soils in the Taupō Volcanic Zone. Remarkably, the bacterium was living in this inhospitable ecosystem despite its soil lacking the nutrients the microbe usually relied on.
This publication is the latest in a trilogy of PNAS papers authored by Professor Cook and former PhD student Dr Chris Greening. Their other recent work showed that soil actinobacteria, another dominant phylum, demonstrate a similar metabolic flexibility in switching to scavenging hydrogen when starved of other nutrients.
L to R: Professor Greg Cook and Dr Chris Greening