Dataset Information

Use of rare-earth elements in the phyllosphere colonizer Methylobacterium extorquens PA1

ABSTRACT: Until recently, rare-earth elements (REEs) had been thought to be biologically inactive. This view changed with the discovery of the methanol dehydrogenase (Mdh) XoxF that strictly relies on REEs for its activity. Some methylotrophs only contain xoxF, while others, including the model phyllosphere colonizer Methylobacterium extorquens PA1, harbor this gene in addition to mxaFI encoding a Ca2+-dependent enzyme. Here we found that REEs induce the expression of xoxF in M. extorquens PA1, while repressing mxaFI, suggesting that XoxF is the preferred Mdh. Using reporter assays and a suppressor screen, we found that La3+ is sensed both in a XoxF-dependent and independent manner. Furthermore, we investigated the role of REEs during Arabidopsis thaliana colonization. Element analysis of the phyllosphere revealed the presence of several REEs at concentrations up to 10 μg per g dry weight. Complementary proteome analyses of M. extorquens PA1 revealed XoxF as a top induced protein in planta and resulted in the identification of a core set of La3+-regulated proteins under defined artificial media conditions. Among these, we identified a potential REE-binding protein that is encoded next to a gene for a TonB-dependent transporter. The latter was essential for REE-dependent growth on methanol indicating chelator-assisted uptake of REEs.

INSTRUMENT(S): Orbitrap Fusion

ORGANISM(S): Methylobacterium Extorquens Pa1

TISSUE(S): Cell Culture

SUBMITTER: Lucas Hemmerle

LAB HEAD: Julia A. Vorholt

PROVIDER: PXD011842 | Pride | 2019-01-21

REPOSITORIES: Pride

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			Action	DRS
	20170315_PhyMo_07_planta_PA1_3.raw	Raw
	20170315_PhyMo_08_plateCLF_PA1_2.raw	Raw
	20170315_PhyMo_12_planta_PA1_1.raw	Raw
	20170315_PhyMo_13_plateCLF_PA1_1.raw	Raw
	20170315_PhyMo_20_platedark_PA1_1.raw	Raw

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Use of rare-earth elements in the phyllosphere colonizer Methylobacterium extorquens PA1.

Ochsner Andrea M AM Hemmerle Lucas L Vonderach Thomas T Nüssli Ralph R Bortfeld-Miller Miriam M Hattendorf Bodo B Vorholt Julia A JA

Molecular microbiology 20190217 5

Until recently, rare-earth elements (REEs) had been thought to be biologically inactive. This view changed with the discovery of the methanol dehydrogenase XoxF that strictly relies on REEs for its activity. Some methylotrophs only contain xoxF, while others, including the model phyllosphere colonizer Methylobacterium extorquens PA1, harbor this gene in addition to mxaFI encoding a Ca<sup>2+</sup> -dependent enzyme. Here we found that REEs induce the expression of xoxF in M. extorquens PA1, whil ...[more]

PMID: 30653750

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