Potential activities of extracellular enzymes in the deep subsurface sediments of the Baltic Sea basin

Author(s): Schmidt, Jenna M.; Steen, Andrew D.
Author Affiliation(s): Primary:
University of Tennessee, Earth & Planetary Sciences Department, Knoxville, TN, United States
Volume Title: Geological Society of America, 2015 annual meeting & exposition
Source: Abstracts with Programs - Geological Society of America, 47(7), p.307; Geological Society of America, 2015 annual meeting & exposition, Baltimore, MD, Nov. 1-4, 2015. Publisher: Geological Society of America (GSA), Boulder, CO, United States. ISSN: 0016-7592 CODEN: GAAPBC
Note: In English
Summary: Heterotrophic microorganisms in sediments produce extracellular enzymes in order to hydrolyze organic macromolecules so that they can be brought inside the cell and used for energy and growth. Extracellular enzymes therefore potentially act as mediators for the fate of organic carbon in sediments. The Baltic Sea Basin presents an excellent opportunity for studying extracellular enzymes and organic carbon degradation because it is a primarily depositional environment with high potential for organic carbon preservation. Using core samples obtained from IODP Expedition 347, the potential activities of multiple carbon degrading enzymes in the deep subsurface of the Baltic Sea Basin were measured using small substrate proxies containing the fluorescent compounds 4-methylumbelliferone (MUB) or 7-amino-4-methylcoumarin (AMC). Here we report the potential maximum hydrolysis rates (Vmax) for the following enzymes in the Baltic Sea subsurface: phosphomonoesterase, β-D-xylosidase, β-D-glucanase, N-acetyl-β-D-glucosaminidase, β-glucosidase, α-glucosidase, leucyl aminopeptidase, arginyl aminopeptidase, prolyl aminopeptidase, ornithyl aminopeptidase, gingipain and clostripain. This work helps to clarify the controls on sedimentary organic matter, and its fate in the marine subsurface. It also provides new insight into the mechanisms and even the limits of microbial life in subsurface ecosystems like the Baltic Sea Basin.
Year of Publication: 2015
Research Program: IODP Integrated Ocean Drilling Program
Key Words: 07 Marine Geology and Oceanography; Atlantic Ocean; Baltic Sea; Expedition 347; Integrated Ocean Drilling Program; Marine sediments; North Atlantic; Sediments
Coordinates: N550000 N625725 E0181530 E0094800
Record ID: 2016025313
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