Soil cyanobacteria are crucial components of biological soil crusts and carry out many functions in dryland ecosystems. Despite this importance, their taxonomy and population genetics remain poorly known. We isolated 42 strains of simple filamentous cyanobacteria previously identified as
Cyanobacteria are diverse prokaryotic, photosynthetic organisms present in nearly every known ecosystem. Recent investigations around the world have recovered vast amounts of novel biodiversity in seldom sampled habitats. One phylogenetically significant character, the secondary folding structures of the 16S–23S ITS rDNA region, has allowed an unprecedented capacity to erect new species. However, two questions arise: Is this feature as informative as is proposed, and how do we best employ these features? Submerged sinkholes with oxygen‐poor, sulfur‐rich ground water in Lake Huron (USA) contain microbial mats dominated by both oxygenic and anoxygenic cyanobacteria. We sought to document some of this unique cyanobacterial diversity. Using culture‐based investigations, we recovered 45 strains, of which 23 were analyzed employing 16S–23S rDNA sequences, ITS folding patterns, ecology, and morphology. With scant morphological discontinuities and nebulous 16S rDNA gene sequence divergence, ITS folding patterns were effective at articulating cryptic biodiversity. However, we would have missed these features had we not folded all the available motifs from the strains, including those with highly similar 16S rDNA gene sequences. If we had relied solely on morphological or 16S rDNA gene data, then we might well have missed the diversity of
- Award ID(s):
- 2046958
- NSF-PAR ID:
- 10422216
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Phycology
- Volume:
- 59
- Issue:
- 3
- ISSN:
- 0022-3646
- Page Range / eLocation ID:
- p. 619-634
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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