Random mutagenesis identifies factors involved in formate-dependent growth of the methanogenic archaeon Methanococcus maripaludis

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Christian Sattler - , TUD Dresden University of Technology, University Hospital Frankfurt (Author)
  • Sandro Wolf - , TUD Dresden University of Technology (Author)
  • Julia Fersch - , TUD Dresden University of Technology (Author)
  • Stefan Goetz - , University Hospital Frankfurt (Author)
  • Michael Rother - , TUD Dresden University of Technology, University Hospital Frankfurt (Author)

Abstract

Methane is a key intermediate in the carbon cycle and biologically produced by methanogenic archaea. Most methanogens are able to conserve energy by reducing CO2 to methane using molecular hydrogen as electron donor (hydrogenotrophic methanogenesis), but several hydrogenotrophic methanogens can also use formate as electron donor for methanogenesis. Formate dehydrogenase (Fdh) oxidizes formate to CO2 and is involved in funneling reducing equivalents into the methanogenic pathway, but details on other factors relevant for formate-dependent physiology of methanogens are not available. To learn more about the factors involved in formate-dependent growth of Methanococcus maripaludis strain JJ, we used a recently developed system for random in vitro mutagenesis, which is based on a modified insect transposable element to create 2,865 chromosomal transposon mutants and screened them for impaired growth on formate. Of 12 M. maripaludis transposon-induced mutants exhibiting this phenotype, the transposon insertion sites in the chromosome were mapped. Among the genes, apparently affecting formate-dependent growth were those encoding archaeal transcription factor S, a regulator of ion transport, and carbon monoxide dehydrogenase/acetyl-CoA synthase. Interestingly, in seven of the mutants, transposons were localized in a 10.2 kb region where Fdh1, one of two Fdh isoforms in the organism, is encoded. Two transcription start sites within the 10.2 kb region could be mapped, and quantification of transcripts revealed that transposon insertion in this region diminished fdhA1 expression due to polar effects.

Details

Original languageEnglish
Pages (from-to)413-424
Number of pages12
JournalMolecular genetics and genomics
Volume288
Issue number9
Publication statusPublished - Sept 2013
Peer-reviewedYes
Externally publishedYes

External IDs

PubMed 23801407

Keywords

ASJC Scopus subject areas

Keywords

  • Formate, Himar1, Methanococcus maripaludis, Methanogenesis, Mutagenesis, Selenocysteine, Transposon