Deep-Sea Genome/Proteome

Deep-Sea Genome/Proteome

Microbial sulfate reduction is an important process in deep-sea habitats. Furthermore deep-sea sulfate reduction is an important component of the oceanic sulphur cycle as a whole. More specifically, this terminal electron accepting pathway is of major importance for the degradation of organic matter in the deep. As described in other blogs, deep-sea wood falls are firstly colonised by heterotrophic bacteria who break down the cellulose and provide substrates for fermentation reactions. From this point sulfate reducing bacteria can use the produced H₂ and create sulfidic niches, which are postulated to attract higher chemosynthetic organisms and their symbionts. Pradel et al. (2013) were interested in one specific sulfate reducing bacteria, Desulfovibrio piezophilus, a piezophilic (organism which thrives at high pressures) anaerobe which was isolated from a wood fall in the Mediterranean. The authors used D.piezophilus as a model organism to study the adaption of sulfate reducing bacteria to high hydrostatic pressure habitats.

Pradel et al. (2013) present the first genomic and proteomic characterisation of a deep-sea sulfate reducer. Briefly, the organism has 3.6Mbp arranged in one circular molecule, a GC content of 50%, 7 genomic islands and 3,424 coding DNA sequences (CDs). Comparing proteomic data at different pressures allowed the detection of pressure related changes in protein production which was speculated to be important points for pressure adaption. Some key enzymes in sulfate reduction were indeed pressure dependant.

On its own this genome/proteome publication is merely another species specific contribution to the literature. However it clearly provides much needed in-depth detail on the structure of the genes and proteins present which could be useful candidates for further work. With the genome/proteome data, there is now opportunity to understand both the deep-sea microbial contribution to the oceanic sulphur cycle and adaption strategies to high pressure environments. Using the candidate genes and proteins identified by this study, further work should include experimental methods to increase understanding of function.

Pradel, N., Ji, B., Gimenez, G., Talla, E., Lenoble, P., Garel, M., Tamburini, C., et al. (2013). The First Genomic and Proteomic Characterization of a Deep-Sea Sulfate Reducer: Insights into the Piezophilic Lifestyle of Desulfovibrio piezophilus. (V. de Crécy-Lagard, Ed.)PLoS ONE, 8(1)

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0055130