Dataset Information

Functional Response of Polar Bacterial Communities under Variable Organic Inputs Revealed with Metaproteomic, 16S rRNA and Organic Compositional Analysis

ABSTRACT: Organic matter recycling in marine systems is largely driven by microbial processes, particularly in the Arctic where primary production and inputs can be temporally offset from upper trophic level consumption. This study followed bacterial dynamics in the chlorophyll maximum of the Bering Strait and sediment-water interface of the Chukchi Sea using metaproteomic and 16S rRNA methods to measure cellular function and taxonomic composition under low and high marine-derived particulate organic matter (POM) treatments at 0°C. Parallel analysis of major organic components (lipids and amino acids) allowed a comparison of microbial-POM interactions. Over the 10 day experimental period, bacteria under both treatments showed rapid community responses and changes in proteomic expression, accompanied by small changes in the concentration and distributions of organic components. In the Bering Strait community, protein translation was an important immediate cellular response under both POM scenarios while specific metabolic processes were more distinct between treatments. For example, under both conditions, evidence for carboxylic acid metabolism increased at day 6 while carbohydrate utilization as an energy source showed unique patterns as the experiments progressed. With POM additions to the Bering Strait community, nitrogen transport and regulation went up, including nitrogen fixation and ammonia assimilation, by day 6. In addition, a number of vitamin enzymatic cofactors were enriched by this day, providing evidence for an increase in C1 metabolism at that time. Low POM conditions stimulated the cycling and synthesis of amino acids, which was not as pronounced under the high POM treatment. In the Chukchi Sea community, nitrate reduction and substrate-specific transporter activity was statistically higher than in the Bering Strait, especially under low POM conditions. Taxonomic inference revealed that a wide range of bacterial classes were associated with the shifting cellular functions, but that Alphaproteobacteria, Gammaproteobacteria and Flavobacteria controlled most of these protein abundances. Activities of all classes were highly variable, with less dominant bacterial groups exhibiting a particularly strong degree of niche separation.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Marine Metagenome

SUBMITTER: Emma Timmins-Schiffman

LAB HEAD: Brook L. Nunn

PROVIDER: PXD008780 | Pride | 2019-02-18

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	2014_Sept_08_BeringSea29.pep.xml	Pepxml
	2014_Sept_08_BeringSea29.raw	Raw
	2014_Sept_08_BeringSea30.pep.xml	Pepxml
	2014_Sept_08_BeringSea30.raw	Raw
	2014_Sept_08_BeringSea32.pep.xml	Pepxml

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Publications

Metaproteomics reveal that rapid perturbations in organic matter prioritize functional restructuring over taxonomy in western Arctic Ocean microbiomes.

Mikan Molly P MP Harvey H Rodger HR Timmins-Schiffman Emma E Riffle Michael M May Damon H DH Salter Ian I Noble William S WS Nunn Brook L BL

The ISME journal 20190906 1

We examined metaproteome profiles from two Arctic microbiomes during 10-day shipboard incubations to directly track early functional and taxonomic responses to a simulated algal bloom and an oligotrophic control. Using a novel peptide-based enrichment analysis, significant changes (p-value < 0.01) in biological and molecular functions associated with carbon and nitrogen recycling were observed. Within the first day under both organic matter conditions, Bering Strait surface microbiomes increased ...[more]

PMID: 31492961

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