@article{07f0c8007d904c358d6cf06c246ac90a,
title = "Methoxyl stable isotopic constraints on the origins and limits of coal-bed methane",
abstract = "Microbial coal-bed methane is an important economic resource and source of a potent greenhouse gas, but controls on its formation are poorly understood. To test whether the microbial degradability of coal limits microbial methane, we monitored methoxyl group demethylation-a reaction that feeds methanogenesis-in a global sample suite ranging in maturity from wood to bituminous coal. Carbon isotopic compositions of residual methoxyl groups were inconsistent with a thermal reaction, instead implying a substrate-limited biologic process. This suggests that deep biosphere communities participated in transforming plant matter to coal on geologic time scales and that methoxyl abundance influences coal-bed methane yield. Carbon isotopic enrichments resulting from microbial methylotrophy also explain an enigmatic offset in the carbon-13 content of microbial methane from coals and conventional hydrocarbon deposits.",
author = "Lloyd, {M. K.} and E. Trembath-Reichert and Dawson, {K. S.} and Feakins, {S. J.} and M. Mastalerz and Orphan, {V. J.} and Sessions, {A. L.} and Eiler, {J. M.}",
note = "Funding Information: We thank K. Snell for use of analytical facilities and M. Formolo and S. Petsch for sharing materials. Shimokita samples were provided by the International Ocean Discovery program. H. L. O. McClelland, D. Stolper, A. Schimmelmann, C. Ponton, and H. Lee provided helpful suggestions at various stages of the project. This work was supported by NSF EAR 1322058 to J.M.E.; a NASA postdoctoral fellowship with the NASA Astrobiology Institute to E.T.-R.; the L'Or{\'e}al USA For Women in Science fellowship to E.T.-R.; the L'Or{\'e}al-UNESCO FWIS International Rising Talent Endowment to E.T.-R.; and the ACS award PRF-53747-ND2 to S.J.F., which initiated their work on this project. Publisher Copyright: {\textcopyright} 2021 American Association for the Advancement of Science. All rights reserved.",
year = "2021",
month = nov,
day = "12",
doi = "10.1126/science.abg0241",
language = "English (US)",
volume = "374",
pages = "894--897",
journal = "Science",
issn = "0036-8075",
publisher = "American Association for the Advancement of Science",
number = "6569",
}