Tetrahydromethanopterin, a carbon carrier in methanogenesis.

Tetrahydromethanopterin, a carbon carrier in methanogenesis.

Evidence obtained by 13C NMR spectroscopy indicates that tetrahydromethanopterin (H4MPT) serves as a carbon carrier for C1 units at the methine, methylene, and methyl levels of oxidation. All three derivatives of H4MPT served as substrates for methanogenesis by cell extracts under a hydrogen atmosphere; in each instance, methane evolved at a rate comparable to that obtained when 2-(methylthio)e...

Tetrahydromethanopterin-dependent methanogenesis from non-physiological C1 donors in Methanobacterium thermoautotrophicum.

Methanogenesis from the non-physiological C1 donors thioproline, thiazolidine, hexamethylenetetramine, formaldehyde (HCHO), and HOCH2-S-coenzyme M (CoM) was catalyzed by cell extracts of Methanobacterium thermoautotrophicum under a hydrogen atmosphere. Tetrahydromethanopterin (H4MPT) and HS-CoM were required in the reaction mixture. The non-physiological compounds were found to be in chemical e...

Methanogenesis involving a novel carrier of C1 compounds in Methanogenium tationis.

The pathway of CO2 reduction to methane in Methanogenium tationis and Methanogenium thermophilicum is similar to that observed in other methanogens. In M. tationis a novel pterin, tatiopterin, is present. This pterin appears to be a structural and functional analog of methanopterin and sarcinapterin. Folate could not substitute for tatiopterin.

Distribution of tetrahydromethanopterin-dependent enzymes in methylotrophic bacteria and phylogeny of methenyl tetrahydromethanopterin cyclohydrolases.

The methylotrophic proteobacterium Methylobacterium extorquens AM1 possesses tetrahydromethanopterin (H(4)MPT)-dependent enzymes, which are otherwise specific to methanogenic and sulfate-reducing archaea and which have been suggested to be involved in formaldehyde oxidation to CO(2) in M. extorquens AM1. The distribution of H(4)MPT-dependent enzyme activities in cell extracts of methylotrophic ...

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