Microbes produce nanobacteria-like structures, avoiding cell entombment

Research Article| August 01, 2008 Microbes produce nanobacteria-like structures, avoiding cell entombment Tomaso R.R. Bontognali; Tomaso R.R. Bontognali 1ETH-Zurich, Geological Institute, Universitätstrasse 16, 8092 Zurich, Switzerland Search for other works by this author on: GSW Google Scholar Crisógono Vasconcelos; Crisógono Vasconcelos 1ETH-Zurich, Geological Institute, Universitätstrasse 16, 8092 Zurich, Switzerland Search for other works by this author on: GSW Google Scholar Rolf J. Warthmann; Rolf J. Warthmann 1ETH-Zurich, Geological Institute, Universitätstrasse 16, 8092 Zurich, Switzerland Search for other works by this author on: GSW Google Scholar Christophe Dupraz; Christophe Dupraz 2Center for Integrative Geosciences, University of Connecticut, 354 Mansfield Road, Storrs, Connecticut 06269, USA Search for other works by this author on: GSW Google Scholar Stefano M. Bernasconi; Stefano M. Bernasconi 1ETH-Zurich, Geological Institute, Universitätstrasse 16, 8092 Zurich, Switzerland Search for other works by this author on: GSW Google Scholar Judith A. McKenzie Judith A. McKenzie 1ETH-Zurich, Geological Institute, Universitätstrasse 16, 8092 Zurich, Switzerland Search for other works by this author on: GSW Google Scholar Geology (2008) 36 (8): 663–666. https://doi.org/10.1130/G24755A.1 Article history received: 07 Jan 2008 rev-recd: 25 Apr 2008 accepted: 04 May 2008 first online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share MailTo Twitter LinkedIn Tools Icon Tools Get Permissions Search Site Citation Tomaso R.R. Bontognali, Crisógono Vasconcelos, Rolf J. Warthmann, Christophe Dupraz, Stefano M. Bernasconi, Judith A. McKenzie; Microbes produce nanobacteria-like structures, avoiding cell entombment. Geology 2008;; 36 (8): 663–666. doi: https://doi.org/10.1130/G24755A.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Microsedimentary structures referred to as nanobacteria-like particles were described from modern carbonate environments, where they form in close spatial association with sulfate-reducing bacteria (SRB). However, the exact mechanism of their formation, as well as their paleontological significance, remains controversial. Here we report on an investigation of microbe-mineral interactions in experimentally produced carbonate globules. The experiments were carried out under anoxic conditions at 30 °C with Desulfovibrio brasiliensis, a SRB known to mediate dolomite formation. We observed that extracellular polymeric substances (EPS) secreted by the microbial community play a key role in the mineralization process. Nanobacteria-like particles represent the early stage of carbonate nucleation within the EPS, which progressively evolve to larger globules displaying a grainy texture. We excluded the possibilities that these structures are fossils of nanobacteria, dissolution surfaces, or artifacts created during sample preparation. D. brasiliensis cells are predominantly located outside of the EPS aggregates where mineral growth takes place. As a result, they remain mobile and are rarely entombed within the mineral. This self-preservation behavior may not be limited to D. brasiliensis. Other microbes may produce, or may have produced during the geological past, biogenic minerals through a similar process. Mineralization within EPS explains why microbial relics are not necessarily present in biogenic carbonates. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.