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Updated: May 10, 2026
10:12
Synchrotron X-ray Microdiffraction and Fluorescence Imaging of Mineral and Rock Samples
Published on: June 19, 2018
Enigmatic reticulated filaments in subsurface granite.
A Z Miller1, M Hernández-Mariné, V Jurado
1Centro de Petrologia e Geoquímica, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001, Lisboa, Portugal.
Environmental Microbiology Reports
|June 14, 2013
Summary
Geomicrobiologists discovered reticulated filaments in a 16th-century tunnel. These manganese-rich nanofiber structures, previously of unknown origin, contain microbial cells, suggesting a microbial role in their formation.
Area of Science:
- Geomicrobiology
- Microbial Ecology
- Geochemistry
Background:
- Reticulated filaments in caves and lava tubes have puzzled geomicrobiologists regarding their origin and nature.
- Previous research has been unable to affiliate these hollow tubular sheaths with known microorganisms, leaving their microbial origin elusive.
Purpose of the Study:
- To investigate the nature and origin of reticulated filaments found in a historical granite tunnel.
- To determine if microbial life is associated with these enigmatic structures.
Main Methods:
- Microscopic and chemical analysis of reticulated filaments from a 16th-century granite tunnel.
- Characterization of nanofiber composition, surface ornamentation, and associated substances.
- Identification of microbial cells within the filament structures.
Main Results:
- Identified reticulated filaments exhibiting fine geometric surface ornamentation in a 16th-century granite tunnel.
- Filaments are composed of cross-linked, manganese-rich nanofibres and abundant extracellular polymeric substances.
- Microbial cells were observed within the manganese-rich filaments for the first time.
Conclusions:
- The findings suggest a microbial origin or involvement in the formation of these reticulated filaments.
- This discovery provides new insights into geomicrobiological processes in historical man-made environments.
- The presence of microbial cells within Mn-rich nanofilaments challenges previous assumptions about their abiotic nature.
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