TY  - JOUR
A1  - Heim, Christine
A1  - Quéric, Nadia-Valérie
A1  - Ionescu, Danny
A1  - Schäfer, Nadine
A1  - Reitner, Joachim
T1  - Frutexites-like structures formed by iron oxidizing biofilms in the continental subsurface (Äspö Hard Rock Laboratory, Sweden)
Y1  - 2017
VL  - 12
IS  - 5
JF  - PLOS ONE
DO  - 10.1371/journal.pone.0177542
DO  - 10.23689/fidgeo-2397
N2  - 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 Frutexites-like biofilm, even though their functional role remains unclear. Biomarker analysis revealed abundant sterols in the biofilm most likely from algal and fungal origins. Our results indicate that the Frutexites-like biofilm was built up by a complex microbial community. The functional role of each community member in the formation of the dendritic structures, as well as their potential relation to fossil Frutexites remains under investigation.
UR  - http://resolver.sub.uni-goettingen.de/purl?gldocs-11858/6710
ER  -