We investigated methane oxidation in the oxygen minimum zone (OMZ) of the eastern tropical North Pacific (ETNP) off central Mexico. Methane concentrations in the anoxic core of the OMZ reached ~ 20 nmol L−1at off shelf sites and 34 nmol L−1at a shelf site. Rates of methane oxidation were determined in ship‐board incubations with3H‐labeled methane at O2concentrations 0–75 nmol L−1. In vertical profiles at off‐shelf stations, highest rates were found between the secondary nitrite maximum at ~ 130 m and the methane maximum at 300–400 m in the anoxic core. Methane oxidation was inhibited by addition of 1
Chemoautotrophic bacteria from the SUP05 clade often dominate anoxic waters within marine oxygen minimum zones (OMZs) where they use energy gained from the oxidation of reduced sulfur to fuel carbon fixation. Some of these SUP05 bacteria are facultative aerobes that can use either nitrate or oxygen as a terminal electron acceptor making them ideally suited to thrive at the boundaries of OMZs where they experience fluctuations in dissolved oxygen (DO). SUP05 metabolism in these regions, and therefore the biogeochemical function of SUP05, depends largely on their sensitivity to oxygen. We evaluated growth and quantified differences in gene expression in
- NSF-PAR ID:
- 10367728
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Environmental Microbiology
- Volume:
- 23
- Issue:
- 6
- ISSN:
- 1462-2912
- Page Range / eLocation ID:
- p. 2823-2833
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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