KNAW Repository

Methane oxidation by an extremely acidophilic bacterium of the phylum Verrucomicrobia

Dunfield, P.F. and Yurgey, A.Q. and Senin, P. and Smirnova, A.V. and Stott, M.B. and Hou, S. and Ly, B. and Saw, J.H. and Zhou, Z. and Ren, Y. and Wang, J. and Mountain, B.W. and Crowe, M.A. and Weatherby, T.M. and Bodelier, P.L.E. and Liesack, W. and Feng, L. and Wang, L. and Alam, M. (2007) Methane oxidation by an extremely acidophilic bacterium of the phylum Verrucomicrobia. Nature, 450, 879-882. ISSN 0028-0836.

[img]PDF - Published Version
Restricted to KNAW only

411Kb

Official URL: http://dx.doi.org/10.1038/nature06411

Abstract

Aerobic methanotrophic bacteria consume methane as it diffuses away from methanogenic zones of soil and sediment1. They act as a biofilter to reduce methane emissions to the atmosphere, and they are therefore targets in strategies to combat global climate change. No cultured methanotroph grows optimally below pH 5, but some environments with active methane cycles are very acidic2, 3. Here we describe an extremely acidophilic methanotroph that grows optimally at pH 2.0–2.5. Unlike the known methanotrophs, it does not belong to the phylum Proteobacteria but rather to the Verrucomicrobia, a widespread and diverse bacterial phylum that primarily comprises uncultivated species with unknown genotypes. Analysis of its draft genome detected genes encoding particulate methane monooxygenase that were homologous to genes found in methanotrophic proteobacteria. However, known genetic modules for methanol and formaldehyde oxidation were incomplete or missing, suggesting that the bacterium uses some novel methylotrophic pathways. Phylogenetic analysis of its three pmoA genes (encoding a subunit of particulate methane monooxygenase) placed them into a distinct cluster from proteobacterial homologues. This indicates an ancient divergence of Verrucomicrobia and Proteobacteria methanotrophs rather than a recent horizontal gene transfer of methanotrophic ability. The findings show that methanotrophy in the Bacteria is more taxonomically, ecologically and genetically diverse than previously thought, and that previous studies have failed to assess the full diversity of methanotrophs in acidic environments.

Item Type:Article
Institutes:Nederlands Instituut voor Ecologie (NIOO)
ID Code:4660
Deposited On:16 Sep 2009 02:00
Last Modified:24 Apr 2012 16:47

Repository Staff Only: item control page