Changing Microspatial Patterns of Sulfate-Reducing Microorganisms (SRM) during Cycling of Marine Stromatolite Mats

International Journal of Molecular Sciences

Alexandru I. Petrisor²  Sandra Szyjka¹  Tomohiro Kawaguchi¹  Pieter T. Visscher³  Robert Sean Norman¹ 

[1]Department of Environmental Health Sciences, Arnold School of Public Health, University of South Carolina, Columbia, SC 29208, USA

[2] E-Mails:

[3]Department of Urban and Landscape Planning, School of Urban Planning, “Ion Mincu” University of Architecture and Urban Planning, str. Academiei nr. 18-20, sector 1, Bucharest 010014, Romania

[4] E-Mail:

[5]Center for Integrative GeoSciences, University of Connecticut, 345 Mansfield Rd., U-2045 Storrs, CT 06269, USA

[6] E-Mail:

关键词: biofilms;    EPS;    microbial mats;    microspatial;    sulfate-reducing microorganisms;    dsrA probe;    chemical signals;    CaCO₃;    AHLs;    ³⁵SO₄ ²⁻ silver-foil;   

DOI  :  10.3390/ijms15010850

来源: mdpi

【 摘 要 】

Microspatial arrangements of sulfate-reducing microorganisms (SRM) in surface microbial mats (~1.5 mm) forming open marine stromatolites were investigated. Previous research revealed three different mat types associated with these stromatolites, each with a unique petrographic signature. Here we focused on comparing “non-lithifying” (Type-1) and “lithifying” (Type-2) mats. Our results revealed three major trends: (1) Molecular typing using the dsrA probe revealed a shift in the SRM community composition between Type-1 and Type-2 mats. Fluorescence in-situ hybridization (FISH) coupled to confocal scanning-laser microscopy (CSLM)-based image analyses, and ³⁵SO₄ ²⁻-silver foil patterns showed that SRM were present in surfaces of both mat types, but in significantly (p < 0.05) higher abundances in Type-2 mats. Over 85% of SRM cells in the top 0.5 mm of Type-2 mats were contained in a dense 130 μm thick horizontal layer comprised of clusters of varying sizes; (2) Microspatial mapping revealed that locations of SRM and CaCO₃ precipitation were significantly correlated (p < 0.05); (3) Extracts from Type-2 mats contained acylhomoserine-lactones (C4-, C6-, oxo-C6 C7-, C8-, C10-, C12-, C14-AHLs) involved in cell-cell communication. Similar AHLs were produced by SRM mat-isolates. These trends suggest that development of a microspatially-organized SRM community is closely-associated with the hallmark transition of stromatolite surface mats from a non-lithifying to a lithifying state.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland