Frutexites-like structures formed by iron oxidizing biofilms in the continental subsurface (Aspo Hard Rock Laboratory, Sweden).

ABSTRACT: Stromatolitic iron-rich structures have been reported from many ancient environments and are often described as Frutexites, a cryptic microfossil. Although microbial formation of such structures is likely, a clear relation to a microbial precursor is lacking so far. Here we report recent iron oxidizing biofilms which resemble the ancient Frutexites structures. The living Frutexites-like biofilms were sampled at 160 m depth in the Äspö Hard Rock Laboratory in Sweden. Investigations using microscopy, 454 pyrosequencing, FISH, Raman spectroscopy, biomarker and trace element analysis allowed a detailed view of the structural components of the mineralized biofilm. The most abundant bacterial groups were involved in nitrogen and iron cycling. Furthermore, Archaea are widely distributed in the Fr

SUBMITTER: Heim C 

PROVIDER: S-EPMC5438144 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature