Methylobacterium is a genus of bacteria, also designated as Pink-Pigmented Facultative Methylotrophs (PPFMs). Methylobacterium is commonly found in soil, water, and particularly in association with the phyllosphere, the aerial part of plants. Methylobacterium is characterized by its ability to metabolize one-carbon compounds like methanol released by plant leaves. Methylobacterium plays key roles in nutrient cycling and plant-microbe interactions, often promoting plant growth and resilience through hormone production and stress mitigation. Methylobacterium is a model in biotechnology, already used commercially for protein production, bioremediation, and as a biostimulant in agriculture. A particular recent interest in the genus has been its role as the best-studied model system for understanding the acquisition, use, and bioaccumulation of lanthanides, also known as rare earth elements.
Methylobacterium has also been identified as a contaminant of DNA extraction kit reagents, which may lead to its erroneous appearance in microbiota or metagenomic datasets. In March 2021, a new species, named Methylobacterium ajmalii,LPSN: Species Methylobacterium ajmalii Bijlani et al. 2021 associated with three new strains, designated IF7SW-B2T, IIF1SW-B5, and IIF4SW-B5, were reported to have been discovered, for the first time, on the International Space Station.
Debate on Methylobacterium taxonomy
In 2018, 11 Methylobacterium species, including Methylobacterium extorquens, were transferred to Methylorubrum. This emendation mostly relied on the 16S rRNA gene phylogeny. In 2021 and 2022, two studies based on phylogenomic and phenotypic data independently pointed the lack of support for Methylorubrum as a distinct genus, calling for its abandonment and the reinstatement of the former Methylobacterium taxonomy. In 2025, despite controversy, and its emendation back to the original Methylobacterium taxonomy, Methylorubrum was still a valid genus name in some databases like NCBI and in the List of Prokaryotic names with Standing in Nomenclature.
Natural genetic transformation
Natural genetic transformation in bacteria is a process involving transfer of DNA from one cell to another through the intervening medium, and the integration of the donor sequence into the recipient genome by homologous recombination. Methylobacterium organophilum cells are able to undergo genetic transformation and become competent for DNA uptake near the end of the exponential growth phase.
Species Methylobacterium comprises the following species (excluding species reclassified in Methylorubrum):
Methylobacterium adhaesivum Gallego et al. 2006 Methylobacterium aerolatum Weon et al. 2008 Methylobacterium ajmalii Bijlani et al. 2021,
Methylobacterium aquaticum Gallego et al. 2005 Methylobacterium brachiatum Kato et al. 2008 Methylobacterium brachythecii Tani and Sahin 2013 Methylobacterium bullatum Hoppe et al. 2012 Methylobacterium cerastii Wellner et al. 2012
Methylobacterium crusticola Jia et al. 2020 Methylobacterium currus Park et al. 2018 Methylobacterium dankookense Lee et al. 2013
Methylobacterium durans Kim et al. 2020
Methylobacterium frigidaeris Lee and Jeon 2018 Methylobacterium fujisawaense Green et al. 1988 "Methylobacterium funariae" Schauer and Kutschera 2011 Methylobacterium gnaphalii Tani et al. 2012 Methylobacterium goesingense Idris et al. 2012 Methylobacterium gossipiicola Madhaiyan et al. 2012 Methylobacterium gregans Kato et al. 2008 Methylobacterium haplocladii Tani and Sahin 2013 Methylobacterium hispanicum Gallego et al. 2005 "Methylobacterium indicum" Chaudhry et al. 2016 Methylobacterium iners Weon et al. 2008 Methylobacterium isbiliense Gallego et al. 2005 Methylobacterium jeotgali Aslam et al. 2007 Methylobacterium komagatae Kato et al. 2008 Methylobacterium longum Knief et al. 2012
Methylobacterium marchantiae Schauer et al. 2011 Methylobacterium mesophilicum (Austin and Goodfellow 1979) Green and Bousfield 1983 Methylobacterium nodulans Jourand et al. 2004 Methylobacterium nonmethylotrophicum Feng et al. 2020 Methylobacterium organophilum Patt et al. 1976 (Approved Lists 1980) Methylobacterium oryzae Madhaiyan et al. 2007 Methylobacterium oryzihabitans Chen et al. 2019 Methylobacterium oxalidis Tani et al. 2012 Methylobacterium persicinum Kato et al. 2008 Methylobacterium phyllosphaerae Madhaiyan et al. 2009 Methylobacterium phyllostachyos Madhaiyan and Poonguzhali 2014 "Methylobacterium planium" Jiang et al. 2020 Methylobacterium platani Kang et al. 2007
Methylobacterium pseudosasicola Madhaiyan and Poonguzhali 2014
Methylobacterium radiotolerans corrig. (Ito and Iizuka 1971) Green and Bousfield 1983
Methylobacterium segetis Ten et al. 2020 Methylobacterium soli Cao et al. 2013
Methylobacterium symbioticum Pascual et al. 2021 Methylobacterium tardum Kato et al. 2008 Methylobacterium tarhaniae Veyisoglu et al. 2013 "Methylobacterium terrae" Kim et al. 2019 Methylobacterium terricola Kim et al. 2020
Methylobacterium thuringiense Wellner et al. 2013 Methylobacterium trifolii Wellner et al. 2013 Methylobacterium variabile Gallego et al. 2005
References
External links MicrobeWiki