Home About Browse Search
Svenska


Oxygen-deficient water zones in the Baltic Sea promote uncharacterized Hg methylating microorganisms in underlying sediments

Capo, Eric and Broman, Elias and Bonaglia, Stefano and Bravo, Andrea G. and Bertilsson, Stefan and Soerensen, Anne L. and Pinhassi, Jarone and Lundin, Daniel and Buck, Moritz and Hall, Per O. J. and Nascimento, Francisco J. A. and Bjorn, Erik (2022). Oxygen-deficient water zones in the Baltic Sea promote uncharacterized Hg methylating microorganisms in underlying sediments. Limnology and Oceanography. 67 :1 , 135-146
[Research article]

[img] PDF
1MB

Abstract

Human-induced expansion of oxygen-deficient zones can have dramatic impacts on marine systems and its resident biota. One example is the formation of the potent neurotoxic methylmercury (MeHg) that is mediated by microbial methylation of inorganic divalent Hg (Hg-II) under oxygen-deficient conditions. A negative consequence of the expansion of oxygen-deficient zones could be an increase in MeHg production due to shifts in microbial communities in favor of microorganisms methylating Hg. There is, however, limited knowledge about Hg-methylating microbes, i.e., those carrying hgc genes critical for mediating the process, from marine sediments. Here, we aim to study the presence of hgc genes and transcripts in metagenomes and metatranscriptomes from four surface sediments with contrasting concentrations of oxygen and sulfide in the Baltic Sea. We show that potential Hg methylators differed among sediments depending on redox conditions. Sediments with an oxygenated surface featured hgc-like genes and transcripts predominantly associated with uncultured Desulfobacterota (OalgD group) and Desulfobacterales (including Desulfobacula sp.) while sediments with a hypoxic-anoxic surface included hgc-carrying Verrucomicrobia, unclassified Desulfobacterales, Desulfatiglandales, and uncharacterized microbes. Our data suggest that the expansion of oxygen-deficient zones in marine systems may lead to a compositional change of Hg-methylating microbial groups in the sediments, where Hg methylators whose metabolism and biology have not yet been characterized will be promoted and expand.

Authors/Creators:Capo, Eric and Broman, Elias and Bonaglia, Stefano and Bravo, Andrea G. and Bertilsson, Stefan and Soerensen, Anne L. and Pinhassi, Jarone and Lundin, Daniel and Buck, Moritz and Hall, Per O. J. and Nascimento, Francisco J. A. and Bjorn, Erik
Title:Oxygen-deficient water zones in the Baltic Sea promote uncharacterized Hg methylating microorganisms in underlying sediments
Series Name/Journal:Limnology and Oceanography
Year of publishing :2022
Volume:67
Number:1
Page range:135-146
Number of Pages:12
Publisher:WILEY
ISSN:0024-3590
Language:English
Publication Type:Research article
Article category:Scientific peer reviewed
Version:Published version
Copyright:Creative Commons: Attribution-Noncommercial-No Derivative Works 4.0
Full Text Status:Public
Subjects:(A) Swedish standard research categories 2011 > 1 Natural sciences > 105 Earth and Related Environmental Sciences > Oceanography, Hydrology, Water Resources
URN:NBN:urn:nbn:se:slu:epsilon-p-114509
Permanent URL:
http://urn.kb.se/resolve?urn=urn:nbn:se:slu:epsilon-p-114509
Additional ID:
Type of IDID
DOI10.1002/lno.11981
Web of Science (WoS)000720132500001
ID Code:27082
Faculty:NJ - Fakulteten för naturresurser och jordbruksvetenskap
Department:(NL, NJ) > Dept. of Aquatic Sciences and Assessment
Deposited By: SLUpub Connector
Deposited On:14 Feb 2022 12:25
Metadata Last Modified:16 May 2022 20:35

Repository Staff Only: item control page

Downloads

Downloads per year (since September 2012)

View more statistics

Downloads
Hits