The origin of aerobic methanotrophy within the Proteobacteria

Journal Article · 04 May 2019 · FEMS Microbiology Letters (Online)

DOI: https://doi.org/10.1093/femsle/fnz096 · OSTI ID:1515086

Kang, Christina S. ^[1]; Dunfield, Peter F. ^[2]; Semrau, Jeremy D. ^[1]

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1. Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, MI, USA 48109-2125
2. Department of Biological Sciences, University of Calgary, Calgary, AB, Canada T2N 1N4

ABSTRACT Aerobic methanotrophs play critical roles in the global carbon cycle, but despite their environmental ubiquity, they are phylogenetically restricted. Via bioinformatic analyses, it is shown that methanotrophy likely arose from methylotrophy from the lateral gene transfer of either of the two known forms of methane monooxygenase (particulate and soluble methane monooxygenases). Moreover, it appears that both known forms of pyrroloquinoline quinone-dependent methanol dehydrogenase (MeDH) found in methanotrophs—the calcium-containing Mxa-MeDH and the rare earth element-containing Xox-MeDH—were likely encoded in the genomes before the acquisition of the methane monooxygenases (MMOs), but that some methanotrophs subsequently received an additional copy of Xox-MeDH-encoding genes via lateral gene transfer. Further, data are presented that indicate the evolution of methanotrophy from methylotrophy not only required lateral transfer of genes encoding for methane monooxygenases, but also likely the pre-existence of a means of collecting copper. Given the emerging interest in valorizing methane via biological platforms, it is recommended that future strategies for heterologous expression of methane monooxygenase for conversion of methane to methanol also include cloning of genes encoding mechanism(s) of copper uptake, especially for expression of particulate methane monooxygenase.

• Research Organization: Univ. of Michigan, Ann Arbor, MI (United States)
• Sponsoring Organization: National Science Foundation; USDOE; USDOE Office of Science (SC), Biological and Environmental Research (BER)
• Grant/Contract Number: SC0018059
• OSTI ID: 1515086
• Journal Information: FEMS Microbiology Letters (Online), Journal Name: FEMS Microbiology Letters (Online) Journal Issue: 9 Vol. 366; ISSN 1574-6968
• Publisher: Federation of European Microbiological SocietiesCopyright Statement
• Country of Publication: Netherlands
• Language: English