Understanding the roles of bacterial communities- 3 months after DWH

The role of sediment-dwelling marine bacteria is poorly understood. The Deepwater Horizon oil spill in New Mexico in 2010 provided an opportunity to study the bacterial communities’ response to the oil. After the wellhead was capped the role of hydrocarbon degradation was predominantly undertaken by bacteria. Using metagenome analysis of communities from 13 samples of sediment along a transect up to 60 km away from the capped wellhead, the bacterial genomes were reconstructed and grouped according to taxa. Majority of the reads were associated with Gammaproteobacteria (66% or 119 Mbp). The same genomes, comprising of six Gammaproteobacteria and two Bacteriodites genome bins were found at all near well sites, at many less impacted or unimpacted distant locations. Depicting a uniform community across the transect.

The metabolic pathways of the community were established from the genes present comparing the sequences to library databases and measuring the abundances in proximal sites and distal sites. 

Genes coding for alkane-degrading pathways were abundant across the transect indicating a selection for alkane degradation in bacteria across the seabed. Enrichment occurring in proximal sites.

The paper explores the roles of the bacterial communities in the sediment in New Mexico, the changes in abundances and reveals the potential of a uniform community in an area with natural hydrocarbon seeps suggesting the retention of Alkane degrading pathways over many generations of bacteria.

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Article reviewed

Handley, K. M., Piceno, Y. M., Hu, P., Tom, L. M., Mason, O. U., Andersen, G. L., ... & Gilbert, J. A. (2017). Metabolic and spatio-taxonomic response of uncultivated seafloor bacteria following the Deepwater Horizon oil spill. The ISME journal, 11(11), 2569.

Available at: https://www.nature.com/articles/ismej2017110