The effect of temperature on sulfur and oxygen isotope fractionation by sulfate reducing bacteria (Desulfococcus multivorans)

Pellerin, André and Antler, Gilad and Marietou, Angeliki and Turchyn, Alexandra V. and Jørgensen, Bo Barker (2020) The effect of temperature on sulfur and oxygen isotope fractionation by sulfate reducing bacteria (Desulfococcus multivorans). FEMS Microbiology Letters, 367 (9). ISSN 1574-6968 DOI https://doi.org/10.1093/femsle/fnaa061

[img] Text
fnaa061.pdf - Published Version
Restricted to Registered users only

Download (415kB) | Request a copy
[img] Archive
fnaa061_supplemental_files.zip - Supplemental Material

Download (2MB)
Official URL: https://doi.org/10.1093/femsle/fnaa061

Abstract

Temperature influences microbiological growth and catabolic rates. Between 15 and 35 °C the growth rate and cell specific sulfate reduction rate of the sulfate reducing bacterium Desulfococcus multivorans increased with temperature. Sulfur isotope fractionation during sulfate reduction decreased with increasing temperature from 27.2 ‰ at 15 °C to 18.8 ‰ at 35 °C which is consistent with a decreasing reversibility of the metabolic pathway as the catabolic rate increases. Oxygen isotope fractionation, in contrast, decreased between 15 and 25 °C and then increased again between 25 and 35 °C, suggesting increasing reversibility in the first steps of the sulfate reducing pathway at higher temperatures. This points to a decoupling in the reversibility of sulfate reduction between the steps from the uptake of sulfate into the cell to the formation of sulfite, relative to the whole pathway from sulfate to sulfide. This observation is consistent with observations of increasing sulfur isotope fractionation when sulfate reducing bacteria are living near their upper temperature limit. The oxygen isotope decoupling may be a first signal of changing physiology as the bacteria cope with higher temperatures.

Item Type: Article
Uncontrolled Keywords: 2020AREP; IA76
Subjects: 01 - Climate Change and Earth-Ocean Atmosphere Systems
Divisions: 01 - Climate Change and Earth-Ocean Atmosphere Systems
Journal or Publication Title: FEMS Microbiology Letters
Volume: 367
Identification Number: https://doi.org/10.1093/femsle/fnaa061
Depositing User: Sarah Humbert
Date Deposited: 01 Jul 2020 00:54
Last Modified: 01 Jul 2020 00:54
URI: http://eprints.esc.cam.ac.uk/id/eprint/4774

Actions (login required)

View Item View Item

About cookies