Hydrocarbon biodegradation by Arctic sea-ice and sub-ice microbial communities during microcosm experiments, Northwest Passage (Nunavut, Canada)

Abstract

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Hydrocarbon-degrading bacteria in deep-water subarctic sediments (Faroe-Shetland Channel)

“…; Garneau et al . ). It is noteworthy that our own experiments using a mixture of aliphatic and aromatic hydrocarbons instead of crude oil in FSC deep‐water sediment incubations did not reveal dominance of Oleispira at any stage of the degradation process, highlighting the importance of substrate type in shaping the response of the bacterial community structure to hydrocarbon contamination (Ferguson et al .…”

Microbial responses to anthropogenic dissolved organic carbon in the Arctic and Antarctic coastal seawaters

“…In Antarctica, at the final time point, they accounted for 0.2% (AE 0.16%) of the total community, suggesting a slower or weaker response to ADOC than the one observed in Arctic waters (Supporting Information Fig. that have been found to be enriched in oil-amendments performed using sub-ice Arctic seawater (Garneau et al, 2016), and in beach sands of the Gulf of Mexico following the Deep Horizon or other oil spills (Rodriguez-R et al, 2015;Joye et al, 2016). Interestingly, in the Arctic, most of the members of the ADOC-enriched taxa corresponded to taxa belonging to the genera Nocardioides, Pseudomonas and Sphingobium, such as Sphingobium japonicum UT26 and Nocardioides sp.…”

“…Flavobacteriia and other bacteria dominated the FA desaturase Pfam that was particularly expressed in Arctic ADOC amendments after 24 h (Fig. 4; Garneau et al, 2016;Newman et al, 2016;Vergeynst et al, 2018). In order to track the second mechanism, we quantified the number of transcripts of isoprenoid biosynthesis, as hopanoids (triterpenes) are synthesized from isoprene.…”

“…Assembly of metagenomic and metatranscriptomic reads was performed with MEGAHIT using default settings (Li et al, 2015) and contigs coverage was quantified by mapping reads to contigs with Bowtie 2 (Langmead and Salzberg, 2012) and then converting to idxstats files with SAMtools (Li et al, 2009). High abundances of unidentified bacteria have been reported previously for Arctic bacterial communities exposed to oil spills (Garneau et al, 2016). After quality-trimming and filtering of added internal standards, between 32.7% and 39.2% of the potential protein-coding reads were taxonomically annotated and between 9.4% and 15.1% of the protein-coding reads had SEED functional annotations (Supporting Information Table S8).…”

Biodegradation of dispersed oil in natural seawaters from Western Greenland and a Norwegian fjord

“…Oil compounds may be degraded by a variety 1 3 of marine microbes, including bacteria, fungi, and algae (Prince 2005). While hydrocarbon-degrading bacteria in temperate seawater usually include members of the classes Alphaproteobacteria and Gammaproteobacteria, oil-polluted Arctic seawater and marine ice often become enriched by Gammaproteobacteria (Bowman and McCuaig 2003;Yakimov et al 2004;Deppe et al 2005;Gerdes et al 2005;Brakstad et al 2008;Bagi et al 2014;McFarlin et al 2014a;Garneau et al 2016). In particular, the Exxon Valdez grounding in Prince Willam Sound in 1989 drew public attention to oil biodegradation of oil discharged in the Arctic, and bioremediation was used as a secondary treatment of stranded oil in the Arctic (Bragg et al 1994).…”