PMID- 28420738
OWN - NLM
STAT- MEDLINE
DCOM- 20170428
LR  - 20240214
IS  - 2150-7511 (Electronic)
VI  - 8
IP  - 2
DP  - 2017 Apr 18
TI  - SAR202 Genomes from the Dark Ocean Predict Pathways for the Oxidation of 
      Recalcitrant Dissolved Organic Matter.
LID - 10.1128/mBio.00413-17 [doi]
LID - e00413-17
AB  - Deep-ocean regions beyond the reach of sunlight contain an estimated 615 Pg of 
      dissolved organic matter (DOM), much of which persists for thousands of years. It 
      is thought that bacteria oxidize DOM until it is too dilute or refractory to 
      support microbial activity. We analyzed five single-amplified genomes (SAGs) from 
      the abundant SAR202 clade of dark-ocean bacterioplankton and found they encode 
      multiple families of paralogous enzymes involved in carbon catabolism, including 
      several families of oxidative enzymes that we hypothesize participate in the 
      degradation of cyclic alkanes. The five partial genomes encoded 152 flavin 
      mononucleotide/F420-dependent monooxygenases (FMNOs), many of which are predicted 
      to be type II Baeyer-Villiger monooxygenases (BVMOs) that catalyze oxygen 
      insertion into semilabile alicyclic alkanes. The large number of oxidative 
      enzymes, as well as other families of enzymes that appear to play complementary 
      roles in catabolic pathways, suggests that SAR202 might catalyze final steps in 
      the biological oxidation of relatively recalcitrant organic compounds to 
      refractory compounds that persist.IMPORTANCE Carbon in the ocean is massively 
      sequestered in a complex mixture of biologically refractory molecules that 
      accumulate as the chemical end member of biological oxidation and diagenetic 
      change. However, few details are known about the biochemical machinery of carbon 
      sequestration in the deep ocean. Reconstruction of the metabolism of a deep-ocean 
      microbial clade, SAR202, led to postulation of new biochemical pathways that may 
      be the penultimate stages of DOM oxidation to refractory forms that persist. 
      These pathways are tied to a proliferation of oxidative enzymes. This research 
      illuminates dark-ocean biochemistry that is broadly consequential for 
      reconstructing the global carbon cycle.
CI  - Copyright (c) 2017 Landry et al.
FAU - Landry, Zachary
AU  - Landry Z
AD  - Department of Microbiology, Oregon State University, Corvallis, Oregon, USA.
FAU - Swan, Brandon K
AU  - Swan BK
AD  - Bigelow Laboratory for Ocean Sciences, Single-Cell Genomics Center, East 
      Boothbay, Maine, USA.
AD  - National Biodefense Analysis and Countermeasures Center, Frederick, Maryland, 
      USA.
FAU - Herndl, Gerhard J
AU  - Herndl GJ
AD  - Department of Marine Biology, University of Vienna, Vienna, Austria.
AD  - Department of Marine Microbiology and Biogeochemistry, NIOZ, Royal Netherlands 
      Institute for Sea Research, Utrecht University, Texel, The Netherlands.
FAU - Stepanauskas, Ramunas
AU  - Stepanauskas R
AD  - Bigelow Laboratory for Ocean Sciences, Single-Cell Genomics Center, East 
      Boothbay, Maine, USA.
FAU - Giovannoni, Stephen J
AU  - Giovannoni SJ
AD  - Department of Microbiology, Oregon State University, Corvallis, Oregon, USA 
      steve.giovannoni@oregonstate.edu.
LA  - eng
GR  - I 486/FWF_/Austrian Science Fund FWF/Austria
GR  - Z 194/FWF_/Austrian Science Fund FWF/Austria
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, Non-P.H.S.
DEP - 20170418
PL  - United States
TA  - mBio
JT  - mBio
JID - 101519231
RN  - 0 (Organic Chemicals)
SB  - IM
MH  - *Genome, Bacterial
MH  - Metabolic Networks and Pathways/*genetics
MH  - *Metagenome
MH  - Oceans and Seas
MH  - Organic Chemicals/*metabolism
MH  - Oxidation-Reduction
MH  - Seawater/*chemistry/*microbiology
PMC - PMC5395668
OTO - NOTNLM
OT  - Chloroflexi
OT  - SAR202
OT  - bathypelagic
OT  - dissolved organic matter
OT  - mesopelagic
OT  - monooxygenase
OT  - single-cell genomics
EDAT- 2017/04/20 06:00
MHDA- 2017/04/30 06:00
PMCR- 2017/04/18
CRDT- 2017/04/20 06:00
PHST- 2017/04/20 06:00 [entrez]
PHST- 2017/04/20 06:00 [pubmed]
PHST- 2017/04/30 06:00 [medline]
PHST- 2017/04/18 00:00 [pmc-release]
AID - mBio.00413-17 [pii]
AID - mBio00413-17 [pii]
AID - 10.1128/mBio.00413-17 [doi]
PST - epublish
SO  - mBio. 2017 Apr 18;8(2):e00413-17. doi: 10.1128/mBio.00413-17.