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Related Articles Barcoded Pyrosequencing Reveals Shared Bacterial Community Properties along Two Alkaline Hot Spring Temperature Gradients in Yellowstone National Park.
Appl Environ Microbiol. 2009 May 8;
Authors: Miller SR, Strong AL, Jones KL, Ungerer MC
Understanding how communities are organized is a fundamental goal of ecology, but one which has historically been elusive for microbial systems. We used a barcoded pyrosequencing approach targeting the V3 region of the bacterial small-subunit ribosomal RNA gene to address the factors that structure communities along the thermal gradients of two alkaline hot springs in the Lower Geyser Basin of Yellowstone National Park. The filtered data set included a total of nearly 34,000 sequences from 39 environmental samples. Each was assigned to one of 391 OTUs identified by their unique V3 sequence signatures. Though the two hot springs differed in OTU composition, community resemblance and diversity changed with strikingly similar dynamics along the two outflow channels. Two lines of evidence suggest that these community properties are primarily controlled by environmental temperature. First, community resemblance decayed exponentially with increasing difference in temperature between samples, but was only weakly correlated with physical distance. Second, diversity decreased with increasing temperature at the same rate along both gradients, but was uncorrelated with other measured environmental variables. This study also provides novel insights into the nature of the ecological interactions among important taxa in these communities. A strong negative association was observed between cyanobacteria and Chloroflexi, which together accounted for approximately 70% of the sequences sampled. This pattern contradicts the longstanding hypothesis that co-adapted lineages of these bacteria maintain tightly co-occurring distributions along these gradients as a result of a producer-consumer relationship. We propose that they instead compete for some limiting resource(s).
PMID: 19429553 [PubMed - as supplied by publisher]
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Related Articles Barcoded Pyrosequencing Reveals Shared Bacterial Community Properties along Two Alkaline Hot Spring Temperature Gradients in Yellowstone National Park.
Appl Environ Microbiol. 2009 May 8;
Authors: Miller SR, Strong AL, Jones KL, Ungerer MC
Understanding how communities are organized is a fundamental goal of ecology, but one which has historically been elusive for microbial systems. We used a barcoded pyrosequencing approach targeting the V3 region of the bacterial small-subunit ribosomal RNA gene to address the factors that structure communities along the thermal gradients of two alkaline hot springs in the Lower Geyser Basin of Yellowstone National Park. The filtered data set included a total of nearly 34,000 sequences from 39 environmental samples. Each was assigned to one of 391 OTUs identified by their unique V3 sequence signatures. Though the two hot springs differed in OTU composition, community resemblance and diversity changed with strikingly similar dynamics along the two outflow channels. Two lines of evidence suggest that these community properties are primarily controlled by environmental temperature. First, community resemblance decayed exponentially with increasing difference in temperature between samples, but was only weakly correlated with physical distance. Second, diversity decreased with increasing temperature at the same rate along both gradients, but was uncorrelated with other measured environmental variables. This study also provides novel insights into the nature of the ecological interactions among important taxa in these communities. A strong negative association was observed between cyanobacteria and Chloroflexi, which together accounted for approximately 70% of the sequences sampled. This pattern contradicts the longstanding hypothesis that co-adapted lineages of these bacteria maintain tightly co-occurring distributions along these gradients as a result of a producer-consumer relationship. We propose that they instead compete for some limiting resource(s).
PMID: 19429553 [PubMed - as supplied by publisher]
More...