Formylmethanofuran—tetrahydromethanopterin N-formyltransferase explained

formylmethanofuran-tetrahydromethanopterin N-formyltransferase
Ec Number:	2.3.1.101
Cas Number:	105669-83-8
Go Code:	0030270
Width:	270

Symbol:	FTR
FTR
Pfam:	PF01913
Interpro:	IPR022667
Scop:	1ftr
Tcdb:	9.A.17

Symbol:	FTR_C
FTR, proximal lobe
Pfam:	PF02741
Interpro:	IPR002770
Scop:	1ftr

In enzymology, a formylmethanofuran-tetrahydromethanopterin N-formyltransferase is an enzyme that catalyzes the chemical reaction

formylmethanofuran + 5,6,7,8-tetrahydromethanopterin

\rightleftharpoons methanofuran + 5-formyl-5,6,7,8-tetrahydromethanopterin

Thus, the two substrates of this enzyme are formylmethanofuran and 5,6,7,8-tetrahydromethanopterin, whereas its two products are methanofuran and 5-formyl-5,6,7,8-tetrahydromethanopterin.

This enzyme belongs to the family of transferases, specifically those acyltransferases transferring groups other than aminoacyl groups. The systematic name of this enzyme class is formylmethanofuran:5,6,7,8-tetrahydromethanopterin 5-formyltransferase. Other names in common use include formylmethanofuran-tetrahydromethanopterin formyltransferase, formylmethanofuran:tetrahydromethanopterin formyltransferase, N-formylmethanofuran(CHO-MFR):tetrahydromethanopterin(H4MPT), formyltransferase, FTR, formylmethanofuran:5,6,7,8-tetrahydromethanopterin, and N5-formyltransferase. This enzyme participates in folate biosynthesis.

Ftr from the thermophilic methanogen Methanopyrus kandleri (which has an optimum growth temperature 98 degrees C) is a hyperthermophilic enzyme that is absolutely dependent on the presence of lyotropic salts for activity and thermostability. The crystal structure of Ftr, determined to a reveals a homotetramer composed essentially of two dimers. Each subunit is subdivided into two tightly associated lobes both consisting of a predominantly antiparallel beta sheet flanked by alpha helices forming an alpha/beta sandwich structure. The approximate location of the active site was detected in a region close to the dimer interface.^[1] Ftr from the mesophilic methanogen Methanosarcina barkeri and the sulphate-reducing archaeon Archaeoglobus fulgidus have a similar structure.^[2]

In the methylotrophic bacterium Methylobacterium extorquens, Ftr interacts with three other polypeptides to form an Ftr/hydrolase complex which catalyses the hydrolysis of formyl-tetrahydromethanopterin to formate during growth on C1 substrates.^[3]

Structural studies

As of late 2007, 5 structures have been solved for this class of enzymes, with PDB accession codes,,,, and .

Further reading

• Donnelly MI, Wolfe RS . 1986 . The role of formylmethanofuran: tetrahydromethanopterin formyltransferase in methanogenesis from carbon dioxide . J. Biol. Chem. . 261 . 16653 - 9 . 3097011 . 35 .
• Leigh JA, Rinehart KL, Wolfe RS . 1984 . Structure of methanofuran, the carbon-dioxide reduction factor of Methanobacterium thermoautotrophicum . J. Am. Chem. Soc. . 106 . 12 . 3636 - 3640 . 10.1021/ja00324a037 .

Notes and References

1. Ermler U, Merckel M, Thauer R, Shima S . Formylmethanofuran: tetrahydromethanopterin formyltransferase from Methanopyrus kandleri - new insights into salt-dependence and thermostability . Structure . 5 . 5 . 635–46 . May 1997 . 9195883 . 10.1016/s0969-2126(97)00219-0. free .
2. Mamat B, Roth A, Grimm C, Ermler U, Tziatzios C, Schubert D, Thauer RK, Shima S . Crystal structures and enzymatic properties of three formyltransferases from archaea: environmental adaptation and evolutionary relationship . Protein Sci. . 11 . 9 . 2168–78 . September 2002 . 12192072 . 2373594 . 10.1110/ps.0211002 .
3. Pomper BK, Saurel O, Milon A, Vorholt JA . Generation of formate by the formyltransferase/hydrolase complex (Fhc) from Methylobacterium extorquens AM1 . FEBS Lett. . 523 . 1–3 . 133–7 . July 2002 . 12123819 . 10.1016/S0014-5793(02)02962-9. 26661124 . free .