Molecular and metabolic characterization of cold-tolerant alpine soil Pseudomonas sensu stricto.
Alpine soils undergo dramatic temporal changes in their microclimatic properties, suggesting that the bacteria there encounter uncommon shifting selection gradients. Pseudomonads constitute important members of the alpine soil community. In order to characterize the alpine Pseudomonas community and to assess the impact of shifting selection on this community, we examined the ability of cold-tolerant Pseudomonas isolates to grow on a variety of carbon sources, and we determined their phylogenetic relationships based on 16S ribosomal DNA sequencing. We found a high prevalence of Pseudomonas in our soil samples, and isolates from these soils exhibited extensive metabolic diversity. In addition, our data revealed that many of our isolates form a unique cold-adapted clade, representatives of which are also found in the Swedish tundra and Antarctica. Our data also show a lack of concordance between the metabolic properties and 16S phylogeny, indicating that the metabolic diversity of these organisms cannot be predicted by phylogeny.
Meyer
A F
AF
Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado 80309, USA.
Lipson
D A
DA
Martin
A P
AP
Schadt
C W
CW
Schmidt
S K
SK
D000531:Altitude; D015373:Bacterial Typing Techniques; D003080:Cold Temperature; D015169:Colony Count, Microbial; D003120:Colorado; D003470:Culture Media; D004269:DNA, Bacterial / Q000032:analysis; D004275:DNA, Ribosomal / Q000032:analysis; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011549:Pseudomonas / Q000145:classification* / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology
D003470:Culture Media; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S