Novel reactions involved in energy conservation by methanogenic archaea

FEBS Lett. 1999 Sep 3;457(3):291-7. doi: 10.1016/s0014-5793(99)01026-1.

Abstract

Methanogenic archaea of the order Methanosarcinales which utilize C(1) compounds such as methanol, methylamines or H(2)+CO(2), employ two novel membrane-bound electron transport systems generating an electrochemical proton gradient: the H(2):heterodisulfide oxidoreductase and the F(420)H(2):heterodisulfide oxidoreductase. The systems are composed of the heterodisulfide reductase and either a membrane-bound hydrogenase or a F(420)H(2) dehydrogenase which is functionally homologous to the proton-translocating NADH dehydrogenase. Cytochromes and the novel electron carrier methanophenazine are also involved. In addition, the methyl-H(4)MPT:HS-CoM methyltransferase is bioenergetically relevant. The enzyme couples methyl group transfer with the translocation of sodium ions and seems to be present in all methanogens. The proton-translocating systems with the participation of cytochromes and methanophenazine have been found so far only in the Methanosarcinales.

Publication types

  • Review

MeSH terms

  • Cytochromes / metabolism
  • Energy Metabolism
  • Euryarchaeota / chemistry
  • Euryarchaeota / classification
  • Euryarchaeota / metabolism*
  • Methyltransferases / chemistry
  • Methyltransferases / metabolism*
  • Oxidation-Reduction
  • Oxidoreductases / chemistry
  • Oxidoreductases / metabolism*
  • Phenazines / chemistry
  • Phenazines / metabolism*

Substances

  • Cytochromes
  • Phenazines
  • methanophenazine
  • Oxidoreductases
  • coenzyme M-7-merceptoheptanoylthreonine-phosphate-heterodisulfide hydrogenase
  • Methyltransferases
  • tetrahydromethanopterin S-methyltransferase