This MedLibrary.org supplementary page on Tetrahydromethanopterin is provided directly from the open source Wikipedia as a service to our readers. Please see the note below on authorship of this content, as well as the Wikipedia usage guidelines. To search for other content from our encyclopedia supplement, please use the form below:
Related Sponsors
| Tetrahydromethanopterin | |
|---|---|
| Identifiers | |
| CAS number | |
| PubChem | |
| Properties | |
| Molecular formula | C30H45N6O16P |
| Molar mass | 776.682661 |
| Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox references |
|
Tetrahydromethanopterin, abbreviated H4MPT, is a coenzyme in methanogenesis. It is the carrier of the C1 group as it is reduced to the methyl level, before transferring to the coenzyme M.1
Tetrahydrosarcinapterin (H4SPT) is a modified form of H4MPT, wherein a glutamyl group linked to the 2-hydroxyglutaric acid terminus.
H4MPT is the main platform for C1 transformations
N-Formylmethanofuran donates the C1 group to the N5 site of the pterin to give the formylH4MPT.2 The formyl group subsequently condenses intramolecularly to give methenylH4MPT+, which is then reduced to methyleneH4MPT.3 MethyleneMPT is subsequently converted, using H2F420 as the electron source, to methylH4MPT, catalyzed by F420-dependent methylene-H4MPT reductase. MethylH4MPT is the methyl donor to coenzyme M, a conversion mediated by methyl-H4MPT:coenzyme M methyl-transferase.1
Comparison with tetrahydrofolate
H4MPT is related to the better known tetrahydrofolate (H4F). The differences are indicated in red and blue in the figure. The most important difference between H4MPT and H4F is that H4F has an electron-withdrawing carbonyl group on the phenyl ring. As a consequence, methenyl-H4MPT is more difficult to reduce than methenyl-H4F. Reduction is effected by a so-called Iron-sulfur cluster free hydrogenase.3 The cumbersome name distinguishes this hydrogenase from the so-called Fe-only hydrogenases that do contain Fe-S cluster.
References
- ^ a b Thauer, R. K., "Biochemistry of Methanogenesis: a tribute to Marjory Stephenson", Microbiology, 1998, 144, 2377-2406.
- ^ Acharya, P.; Warkentin, E.; Ermler, U.; Thauer, R. K.; Shima, S., "The Structure of Formylmethanofuran:Tetrahydromethanopterin Formyltransferase in Complex with its Coenzymes", Journal of Molecular Biology, 2006, volume 357, pages 870-879.
- ^ a b Korbas, M.; Vogt, S.; Meyer-Klaucke, W.; Bill, E.; Lyon, E. J.; Thauer, R. K. and Shima, S., "The Iron-Sulfur Cluster-free Hydrogenase (Hmd) Is a Metalloenzyme with a Novel Iron Binding Motif", Journal of Biological Chemistry, 2006, volume 281, pages 30804-30813.
|
||||||||||||||
Wikipedia content modification information:
- This page was last modified on 11 October 2008, at 02:29.
Wikipedia Authorship and Review
Wikipedia content provided here is not reviewed directly by MedLibrary.org. Wikipedia content is authored by an open community of volunteers and is not produced by or in any way affiliated with MedLibrary.org.
Wikipedia Usage Guidelines
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article on "Tetrahydromethanopterin".
The URL for this specific entry is:
All Wikipedia text is available under the terms of the GNU Free Documentation License. (See Copyrights for details). Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc.
