TY - JOUR
T1 - The biogeochemical sulfur cycle of marine sediments
AU - Jørgensen, Bo Barker
AU - Findlay, Alyssa J.
AU - Pellerin, André
PY - 2019/4
Y1 - 2019/4
N2 - Microbial dissimilatory sulfate reduction to sulfide is a predominant terminal pathway of organic matter mineralization in the anoxic seabed. Chemical or microbial oxidation of the produced sulfide establishes a complex network of pathways in the sulfur cycle, leading to intermediate sulfur species and partly back to sulfate. The intermediates include elemental sulfur, polysulfides, thiosulfate, and sulfite, which are all substrates for further microbial oxidation, reduction or disproportionation. New microbiological discoveries, such as long-distance electron transfer through sulfide oxidizing cable bacteria, add to the complexity. Isotope exchange reactions play an important role for the stable isotope geochemistry and for the experimental study of sulfur transformations using radiotracers. Microbially catalyzed processes are partly reversible whereby the back-reaction affects our interpretation of radiotracer experiments and provides a mechanism for isotope fractionation. We here review the progress and current status in our understanding of the sulfur cycle in the seabed with respect to its microbial ecology, biogeochemistry, and isotope geochemistry.
AB - Microbial dissimilatory sulfate reduction to sulfide is a predominant terminal pathway of organic matter mineralization in the anoxic seabed. Chemical or microbial oxidation of the produced sulfide establishes a complex network of pathways in the sulfur cycle, leading to intermediate sulfur species and partly back to sulfate. The intermediates include elemental sulfur, polysulfides, thiosulfate, and sulfite, which are all substrates for further microbial oxidation, reduction or disproportionation. New microbiological discoveries, such as long-distance electron transfer through sulfide oxidizing cable bacteria, add to the complexity. Isotope exchange reactions play an important role for the stable isotope geochemistry and for the experimental study of sulfur transformations using radiotracers. Microbially catalyzed processes are partly reversible whereby the back-reaction affects our interpretation of radiotracer experiments and provides a mechanism for isotope fractionation. We here review the progress and current status in our understanding of the sulfur cycle in the seabed with respect to its microbial ecology, biogeochemistry, and isotope geochemistry.
KW - Stable isotopes
KW - Sulfate reducing bacteria
KW - Sulfate reduction
KW - Sulfide oxidation
KW - Sulfide oxidizing bacteria
KW - Sulfur disproportionation
KW - Sulfur isotope fractionation
UR - http://www.scopus.com/inward/record.url?scp=85068150914&partnerID=8YFLogxK
U2 - 10.3389/fmicb.2019.00849
DO - 10.3389/fmicb.2019.00849
M3 - Journal article
C2 - 31105660
AN - SCOPUS:85068150914
SN - 1664-302X
VL - 10
JO - Frontiers in Microbiology
JF - Frontiers in Microbiology
M1 - 849
ER -