Exiguobacterium antarcticum is a psychotropic bacterium isolated for the first time from microbial mats of Lake Fryxell in Antarctica. Many organisms of the genus Exiguobacterium are extremophiles and have properties of biotechnological interest, e.g., the capacity to adapt to cold, which make this genus a target for discovering new enzymes, such as lipases and proteases, in addition to improving our understanding of the mechanisms of adaptation and survival at low temperatures. This study presents the genome of E. antarcticum B7, isolated from a biofilm sample of Ginger Lake on King George Island, Antarctic peninsula.
BackgroundExiguobacterium antarcticum strain B7
is a Gram-positive psychrotrophic bacterial species isolated in
Antarctica. Although this bacteria has been poorly studied, its genome
has already been sequenced. Therefore, it is an appropriate model for the
study of thermal adaptation. In the present study, we analyzed the
transcriptomes and proteomes of E.
antarcticum B7 grown at 0°C and 37°C by SOLiD RNA-Seq, Ion
Torrent RNA-Seq and two-dimensional difference gel electrophoresis tandem
mass spectrometry (2D-DIGE-MS/MS).ResultsWe found expression of 2,058 transcripts in all replicates from both
platforms and differential expression of 564 genes (absolute log2FC ≥1,
P-value <0.001) comparing the two temperatures by RNA-Seq. A total of
73 spots were differentially expressed between the two temperatures on
2D-DIGE, 25 of which were identified by MS/MS. Some proteins exhibited
patterns of dispersion in the gel that are characteristic of
post-translational modifications.ConclusionsOur findings suggest that the two sequencing platforms yielded similar
results and that different omic approaches may be used to improve the
understanding of gene expression. To adapt to low temperatures, E. antarcticum B7 expresses four of the six
cold-shock proteins present in its genome. The cold-shock proteins were
the most abundant in the bacterial proteome at 0°C. Some of the
differentially expressed genes are required to preserve transcription and
translation, while others encode proteins that contribute to the
maintenance of the intracellular environment and appropriate protein
folding. The results denote the complexity intrinsic to the adaptation of
psychrotrophic organisms to cold environments and are based on two omic
approaches. They also unveil the lifestyle of a bacterial species
isolated in Antarctica.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2164-15-986) contains supplementary material, which is available to
authorized users.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.