Rapid reactivation of deep subsurface microbes in the presence of C-1 compounds

Microorganisms in the deep biosphere are believed to conduct little metabolic activity due to low nutrient availability in these environments. However, destructive penetration to long-isolated bedrock environments during construction of underground waste repositories can lead to increased nutrient availability and potentially affect the long-term stability of the repository systems. Here we studied how microorganisms present in fracture fluid from a depth of 1500 m in Outokumpu, Finland respond to simple carbon compounds (C-1 compounds) in the presence or absence of sulphate as an electron acceptor.