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.2014 Jan;8(1):139-49.
doi: 10.1038/ismej.2013.140. Epub 2013 Aug 29.

Bacterial genome replication at subzero temperatures in permafrost

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Bacterial genome replication at subzero temperatures in permafrost

Steven J Tuorto et al. ISME J.2014 Jan.

Abstract

Microbial metabolic activity occurs at subzero temperatures in permafrost, an environment representing ∼25% of the global soil organic matter. Although much of the observed subzero microbial activity may be due to basal metabolism or macromolecular repair, there is also ample evidence for cellular growth. Unfortunately, most metabolic measurements or culture-based laboratory experiments cannot elucidate the specific microorganisms responsible for metabolic activities in native permafrost, nor, can bulk approaches determine whether different members of the microbial community modulate their responses as a function of changing subzero temperatures. Here, we report on the use of stable isotope probing with (13)C-acetate to demonstrate bacterial genome replication in Alaskan permafrost at temperatures of 0 to -20 °C. We found that the majority (80%) of operational taxonomic units detected in permafrost microcosms were active and could synthesize (13)C-labeled DNA when supplemented with (13)C-acetate at temperatures of 0 to -20 °C during a 6-month incubation. The data indicated that some members of the bacterial community were active across all of the experimental temperatures, whereas many others only synthesized DNA within a narrow subzero temperature range. Phylogenetic analysis of (13)C-labeled 16S rRNA genes revealed that the subzero active bacteria were members of the Acidobacteria, Actinobacteria, Chloroflexi, Gemmatimonadetes and Proteobacteria phyla and were distantly related to currently cultivated psychrophiles. These results imply that small subzero temperature changes may lead to changes in the active microbial community, which could have consequences for biogeochemical cycling in permanently frozen systems.

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Figures

Figure 1
Figure 1
Schematic of SIP/carrier method and TRFLP analysis. Separation of12C and13C-DNA in a cesium gradient allows for the fingerprinting of the resident members (blue profile) and active members (red profile) of the bacterial community. The13C experimental treatment (top path) yields amplification in the carrier band (red peaks), whereas the12C-control incubations (bottom path) have no PCR/TRFLP signal in the carrier band (red flat-line).
Figure 2
Figure 2
Representative control and experimental SIP profiles from the −20 °C permafrost incubations. (a) Control12C-acetate treatment demonstrating the resident (blue) and active (red) community fingerprints. (b) Experimental13C-acetate treatment with resident (blue) and active (red) profiles. (c) Composite profiles from the replicate13C- treatments with the resident profiles (blue line/above axis) and the active profiles (red line/below axis). Specific TRFs that are suppressed (dashed arrows) or enriched (solid arrows) are indicated.
Figure 3
Figure 3
Heat map displaying relative contribution (see color key) of active bacterial OTUs (y axis) in the permafrost-community profiles at the various incubation temperatures (x axis). The OTUs that were cloned and sequenced in the current study are denoted by colored circles on they axis (also see Figure 4).
Figure 4
Figure 4
Maximum likelihood phylogenetic tree reconstruction of 16S rRNA genes from the13C-DNA fraction from the −9 and −20 °C incubations with cultivated psychroactive strains, uncultured phylotypes and other representative species (784 unambiguously aligned bases and 91 taxa). The13C-labeled TRFs from this study and their respective temperature grouping are indicated by colored circles (see also Figure 3). Source habitat information and GenBank accession numbers of ALL taxa included in the tree construction are presented in Supplementary Table S2.
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References

    1. Babcock DA, Wawrik B, Paul JH, McGuinness L, Kerkhof LJ. Rapid screening of a large insert BAC library for specific 16S rRNA genes using TRFLP. J Microbiol Meth. 2007;71:156–161. - PubMed
    1. Bakermans C, Nealson KH. Relationship of critical temperature to macromolecular synthesis and growth yield in Psychrobacter cryopegella. J Bacteriol. 2004;186:2340–2345. - PMC - PubMed
    1. Bergholz PW, Bakermans C, Tiedje JM. Psychrobacter arcticus 273-4 uses resource efficiency and molecular motion adaptations for subzero temperature growth. J Bacteriol. 2009;191:2340–2352. - PMC - PubMed
    1. Bowman JS, Deming JW.2010Elevated bacterial abundance and exopolymers in saline frost flowers and implications for atmospheric chemistry and microbial dispersal Geophys Res Lett 37doi: 10.1029/2010GL043020 - DOI
    1. Carpenter EJ, Lin S, Capone DG. Bacterial activity in South Pole Snow. Appl Environ Microbiol. 2000;66:4514–4517. - PMC - PubMed

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