Involvement of methyltransferase-activating protein and methyltransferase 2 isoenzyme II in methylamine:coenzyme M methyltransferase reactions in Methanosarcina barkeri Fusaro.
AUTOR(ES)
Wassenaar, R W
RESUMO
The enzyme systems involved in the methyl group transfer from methanol and from tri- and dimethylamine to 2-mercaptoethanesulfonic acid (coenzyme M) were resolved from cell extracts of Methanosarcina barkeri Fusaro grown on methanol and trimethylamine, respectively. Resolution was accomplished by ammonium sulfate fractionation, anion-exchange chromatography, and fast protein liquid chromatography. The methyl group transfer reactions from tri- and dimethylamine, as well as the monomethylamine:coenzyme M methyltransferase reaction, were strictly dependent on catalytic amounts of ATP and on a protein present in the 65% ammonium sulfate supernatant. The latter could be replaced by methyltransferase-activating protein isolated from methanol-grown cells of the organism. In addition, the tri- and dimethylamine:coenzyme M methyltransferase reactions required the presence of a methylcobalamin:coenzyme M methyltransferase (MT2), which is different from the analogous enzyme from methanol-grown M. barkeri. In this work, it is shown that the various methylamine:coenzyme M methyltransfer steps proceed in a fashion which is mechanistically similar to the methanol:coenzyme M methyl transfer, yet with the participation of specific corrinoid enzymes and a specific MT2 isoenzyme.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=178596Documentos Relacionados
- Immunocytochemical localization of the coenzyme F420-reducing hydrogenase in Methanosarcina barkeri Fusaro.
- Molecular, genetic, and biochemical characterization of the serC gene of Methanosarcina barkeri Fusaro.
- Reconstitution of trimethylamine-dependent coenzyme M methylation with the trimethylamine corrinoid protein and the isozymes of methyltransferase II from Methanosarcina barkeri.
- Involvement of an activation protein in the methanol:2-mercaptoethanesulfonic acid methyltransferase reaction in Methanosarcina barkeri.
- Methylthiol:coenzyme M methyltransferase from Methanosarcina barkeri, an enzyme of methanogenesis from dimethylsulfide and methylmercaptopropionate.
