Microbial Communities across Global Marine Basins Show Important Compositional Similarities by Depth

Abstract

The environmental surveys following the 2010 Deepwater Horizon (DWH) spill identified a variety of hydrocarbon-degrading microorganisms, and laboratory studies with field-collected water samples then demonstrated faster-than-expected hydrocarbon biodegradation rates at 5°C. Knowledge about microbial community composition, diversity, and functional metabolic capabilities aids in understanding and predicting petroleum biodegradation by microbial communities in situ and is therefore an important component of the petroleum spill response decision-making process. This study investigates the taxonomic composition of microbial communities in six different global basins where petroleum and gas activities occur. Shallow-water communities were strikingly similar across basins, while deep-water communities tended to show subclusters by basin, with communities from the epipelagic, mesopelagic, and bathypelagic zones sometimes appearing within the same cluster. Microbial taxa that were enriched in the water column in the Gulf of Mexico following the DWH spill were found across marine basins. Several hydrocarbon-degrading genera (e.g., Actinobacteria, Pseudomonas, and Rhodobacteriacea) were common across all basins. Other genera such as Pseudoalteromonas and Oleibacter were highly enriched in specific basins. IMPORTANCE Marine microbial communities are a vital component of global carbon cycling, and numerous studies have shown that populations of petroleum-degrading bacteria are ubiquitous in the oceans. Few studies have attempted to distinguish all of the taxa that might contribute to petroleum biodegradation (including, e.g., heterotrophic and nondesignated microbes that respond positively to petroleum and microbes that grow on petroleum as the sole carbon source). This study quantifies the subpopulations of microorganisms that are expected to be involved in petroleum hydrocarbon biodegradation, which is important information during the decision-making process in the event of a petroleum spill accident.

Comparison of Hydrocarbon-Degrading Consortia from Surface and Deep Waters of the Eastern Mediterranean Sea: Characterization and Degradation Potential

“…Yet, Q10 remains close to 1 for all hydrocarbon fractions, demonstrating the adaptation of deep-water microbes in the Eastern Mediterranean to ambient conditions and their ability to degrade hydrocarbons at comparable, if not greater, rates to surface communities. Our results confirm findings of faster-than-expected hydrocarbon degradation rates in deep waters of the GoM following DWH [48].…”

Metagenomics and Quantitative Stable Isotope Probing Offer Insights into Metabolism of Polycyclic Aromatic Hydrocarbon Degraders in Chronically Polluted Seawater

“…Previous studies revealed that in many systems bioremediation of crude oil can be enhanced by addition of nitrogen and phosphorus ( 17 , 63 ). While oil-degrading bacteria are found in many marine systems ( 64 ), their metabolic requirements may vary by system, depending on limitations in situ . The significant genomic dissimilarity between the strains of Colwellia and Cycloclasticus found at POLA and the ones found at the Gulf of Mexico implies that we cannot assume similarity in metabolic requirements between systems.…”

Environmental Factors Associated with the Eukaryotic Microbial Community and Microalgal Groups in the Mountain Marshes of South Korea

“…While 68.71% of the microbial community in Jeonglyeongchi was dominated by one species belonging to Platyhelminthes, the microbial community of Weagok and Wangdeungjae was composed of several species belonging to 3–4 phyla ( Table II ). Thus, it is believed that the similarity between microbial communities does not depend on diversity indicators ( Miller et al 2020 ; Wen et al 2020 ). Nonetheless, we support that the comparison between microbial communities should be accompanied by a composition comparison factor ( Shi et al 2020 ).…”