1 research outputs found
Environmental controls and composition of anoxygenic photoheterotrophs in ultraoligotrophic high-altitude lakes (Central Pyrenees)
7 páginas, 4 figuras.The phylogenetic composition of freshwater anoxygenic
photoheterotrophs (APs) has been poorly
investigated as compared with their marine counterparts.
In this study, we explored a set of
ultraoligotrophic cold high mountain lakes (Central
Pyrenees, Spain) by both pufM gene denaturing gradient
gel electrophoresis fingerprinting, and cloning
and sequencing of selected lakes samples. Different
ranges of limnological and physico-chemical values
were explored as environmental drivers of APs richness
and composition. We did not observe significant
relationships between richness/diversity of
pufM and any of the limnological characteristics
measured or trophic status, but a negative correlation
with ammonia concentration. Conductivity, pH
and nitrate concentration were significantly related
to changes in APs community composition, whereas
lake area, altitude, temperature and trophic status
did not. Most of the sequences (> 85%) had the pufM
sequences of Limnohabitans (Betaproteobacteria)
as the closest relative in databases, whereas less
abundant clones were more closely related to
Rhodobacter, Sulfitobacter and Brevundimonas
(Alphaproteobacteria), in agreement with 16S rRNA
gene sequences previously found in the area.
Congregibacter-like Gammaproteobacteria were not
detected. Comparison with available studies in
inland waters showed taxonomic partitioning along
salinity gradients, and Congregibacter-like sequences
restricted to high saline conditions in continental
water bodies.This research was supported by grant
DARKNESS CGL2012-32747 from the Spanish Office of
Science (MINECO).Peer reviewe