Tetrahydromethanopterin

Tetrahydromethanopterin (THMPT, H
₄MPT) 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]

Tetrahydromethanopterin

Identifiers
CAS Number	92481-94-2 N
3D model (JSmol)	Interactive image
ChemSpider	4573696 Y
PubChem CID	5462234
CompTox Dashboard (EPA)	DTXSID70919150
InChI InChI=1S/C30H45N6O16P/c1-12(21-13(2)33-26-22(34-21)27(44)36-30(31)35-26)32-15-5-3-14(4-6-15)9-16(37)23(41)17(38)10-49-29-25(43)24(42)19(51-29)11-50-53(47,48)52-18(28(45)46)7-8-20(39)40/h3-6,12-13,16-19,21,23-25,29,32,34,37-38,41-43H,7-11H2,1-2H3,(H,39,40)(H,45,46)(H,47,48)(H4,31,33,35,36,44)/t12-,13+,16+,17-,18+,19-,21?,23+,24-,25-,29+/m1/s1 Y Key: SCBIBGUJSMHIAI-FDLOOEGASA-N Y InChI=1/C30H45N6O16P/c1-12(21-13(2)33-26-22(34-21)27(44)36-30(31)35-26)32-15-5-3-14(4-6-15)9-16(37)23(41)17(38)10-49-29-25(43)24(42)19(51-29)11-50-53(47,48)52-18(28(45)46)7-8-20(39)40/h3-6,12-13,16-19,21,23-25,29,32,34,37-38,41-43H,7-11H2,1-2H3,(H,39,40)(H,45,46)(H,47,48)(H4,31,33,35,36,44)/t12-,13+,16+,17-,18+,19-,21?,23+,24-,25-,29+/m1/s1 Key: SCBIBGUJSMHIAI-FDLOOEGABF
SMILES O=C2/N=C(/N)NC=1N[C@@H](C)C(NC=12)[C@H](Nc3ccc(cc3)C[C@H](O)[C@H](O)[C@H](O)CO[C@H]4O[C@@H]([C@@H](O)[C@H]4O)COP(=O)(O[C@H](C(=O)O)CCC(=O)O)O)C
Properties
Chemical formula	C 30H 45N 6O 16P
Molar mass	776.682661
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Tetrahydrosarcinapterin (THSPT, H
₄SPT) is a modified form of THMPT, wherein a glutamyl group linked to the 2-hydroxyglutaric acid terminus.

THMPT is the main platform for C1 transformations

N-Formylmethanofuran donates the C1 group to the N5 site of the pterin to give the formyl- THMPT.^[2] The formyl group subsequently condenses intramolecularly to give methenyl- THMPT⁺
, which is then reduced to methylene- THMPT.^[3] Methylene- MPT is subsequently converted, using coenzyme F₄₂₀ as the electron source, to methyl- THMPT, catalyzed by F₄₂₀-dependent methylene-THMPT reductase. Methyl- THMPT is the methyl donor to coenzyme M, a conversion mediated by methyl-THMPT:coenzyme M methyltransferase.^[1]

Comparison with tetrahydrofolic acid

THMPT is related to the better known tetrahydrofolic acid (THFA, H
₄FA). The most important difference between THMPT and THFA is that THFA has an electron-withdrawing carbonyl group on the phenyl ring. As a consequence, methenyl- THMPT is more difficult to reduce than methenyl- THFA. 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

1. Thauer RK (September 1998). "Biochemistry of methanogenesis: a tribute to Marjory Stephenson. 1998 Marjory Stephenson Prize Lecture". Microbiology. 144 (Pt 9): 2377–406. doi:10.1099/00221287-144-9-2377. PMID 9782487.
2. Acharya P, Warkentin E, Ermler U, Thauer RK, Shima S (March 2006). "The structure of formylmethanofuran: tetrahydromethanopterin formyltransferase in complex with its coenzymes". J. Mol. Biol. 357 (3): 870–9. doi:10.1016/j.jmb.2006.01.015. PMID 16466742.
3. Korbas M, Vogt S, Meyer-Klaucke W, et al. (October 2006). "The iron-sulfur cluster-free hydrogenase (Hmd) is a metalloenzyme with a novel iron binding motif". J. Biol. Chem. 281 (41): 30804–13. doi:10.1074/jbc.M605306200. PMID 16887798.