Fine-Scale Distribution Patterns of Synechococcus Ecological Diversity in Microbial Mats of Mushroom Spring, Yellowstone National Park

Eric D. Becraft, Frederick M. Cohan, Michael Kühl, Sheila Ingemann Jensen, David M. Ward

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

Past analyses of sequence diversity in high-resolution protein-encoding genes have identified putative ecological species of unicellular cyanobacteria in the genus Synechococcus, which are specialized to 60°C but not 65°C in Mushroom Spring microbial mats. Because these studies were limited to only two habitats, we studied the distribution of Synechococcus sequence variants at 1°C intervals along the effluent flow channel and at 80-tim vertical-depth intervals throughout the upper photic layer of the microbial mat. Diversity at the psaA locus, which encodes a photosynthetic reaction center protein (PsaA), was sampled by PCR amplification, cloning, and sequencing methods at 60, 63, and 65°C sites. The evolutionary simulation programs Ecotype Simulation and AdaptML were used to identify putative ecologically distinct populations (ecotypes). Ecotype Simulation predicted a higher number of putative ecotypes in cases where habitat variation was limited, while AdaptML predicted a higher number of ecologically distinct phylogenetic clades in cases where habitat variation was high. Denaturing gradient gel electrophoresis was used to track the distribution of dominant sequence variants of ecotype populations relative to temperature variation and to °2' pH, and spectral irradiance variation, as measured using microsensors. Different distributions along effluent channel flow and vertical gradients, where temperature, light, and O2 concentrations are known to vary, confirmed the ecological distinctness of putative ecotypes.
Original languageEnglish
JournalApplied and Environmental Microbiology
Volume77
Issue number21
Pages (from-to)7689-7697
ISSN0099-2240
DOIs
Publication statusPublished - 2011
Externally publishedYes

Fingerprint Dive into the research topics of 'Fine-Scale Distribution Patterns of Synechococcus Ecological Diversity in Microbial Mats of Mushroom Spring, Yellowstone National Park'. Together they form a unique fingerprint.

Cite this