Send to

Choose Destination
Biochim Biophys Acta. 2001 May 1;1505(1):28-36.

The Na(+)-translocating methyltransferase complex from methanogenic archaea.

Author information

Institut für Mikrobiologie und Genetik, Georg-August-Universität Göttingen, Germany.


Methanogenic archaea are dependent on sodium ions for methane formation. A sodium ion-dependent step has been shown to be methyl transfer from N(5)-methyltetrahydromethanopterin to coenzyme M. This exergonic reaction (DeltaG degrees '=-30 kJ/mol) is catalyzed by a Na(+)-translocating membrane-associated multienzyme complex composed of eight different subunits, MtrA-H. Subunit MtrA harbors a cob(I)amide prosthetic group which is methylated and demethylated in the catalytic cycle, demethylation being sodium ion-dependent. Based on the finding that in the cob(II)amide oxidation state the corrinoid is bound in a base-off/His-on configuration it is proposed that methyl transfer from MtrA to coenzyme M is associated with a conformational change of the protein and that this change drives the electrogenic translocation of the sodium ions.

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center