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  • Gene products and processes contributing to lanthanide homeostasis and methanol metabolism in Methylorubrum extorquens AM1
Title: Gene products and processes contributing to lanthanide homeostasis and methanol metabolism in Methylorubrum extorquens AM1
Abstract Lanthanide elements have been recently recognized as “new life metals” yet much remains unknown regarding lanthanide acquisition and homeostasis. InMethylorubrum extorquensAM1, the periplasmic lanthanide-dependent methanol dehydrogenase XoxF1 produces formaldehyde, which is lethal if allowed to accumulate.This property enabled a transposon mutagenesis study and growth studies to confirm novel gene products required for XoxF1 function. The identified genes encode an MxaD homolog,an ABC-type transporter, an aminopeptidase, a putative homospermidine synthase, and two genes of unknown function annotated asorf6andorf7. Lanthanide transport and trafficking genes were also identified. Growth and lanthanide uptake were measured using strains lacking individual lanthanide transport cluster genes, and transmission electron microscopy was used to visualize lanthanide localization. We corroborated previous reports that a TonB-ABC transport system is required for lanthanide incorporation to the cytoplasm. However, cells were able to acclimate over time and bypass the requirement for the TonB outer membrane transporter to allow expression ofxoxF1and growth. Transcriptional reporter fusions show that excess lanthanides repress the gene encoding the TonB-receptor. Using growth studies along with energy dispersive X-ray spectroscopy and transmission electron microscopy, we demonstrate that lanthanides are stored as cytoplasmic inclusions that resemble polyphosphate granules.  more » « less
Award ID(s):
1750003
PAR ID:
10176830
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Nature Publishing Group
Date Published:
Journal Name:
Scientific Reports
Volume:
10
Issue:
1
ISSN:
2045-2322
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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