TY  - JOUR
A1  - Upadhyay, Vikrant
A1  - Ceh, Katharina
A1  - Tumulka, Franz
A1  - Abele, Rupert
A1  - Hoffmann, Jan
A1  - Langer, Julian David
A1  - Shima, Seigo
A1  - Ermler, Ulrich
T1  - Molecular characterization of methanogenic N(5)-methyl-tetrahydromethanopterin : coenzyme M methyltransferase
T2  - Biochimica et biophysica acta
N2  - Methanogenic archaea share one ion gradient forming reaction in their energy metabolism catalyzed by the membrane-spanning multisubunit complex N5-methyl-tetrahydromethanopterin: coenzyme M methyltransferase (MtrABCDEFGH or simply Mtr). In this reaction the methyl group transfer from methyl-tetrahydromethanopterin to coenzyme M mediated by cobalamin is coupled with the vectorial translocation of Na+ across the cytoplasmic membrane. No detailed structural and mechanistic data are reported about this process. In the present work we describe a procedure to provide a highly pure and homogenous Mtr complex on the basis of a selective removal of the only soluble subunit MtrH with the membrane perturbing agent dimethyl maleic anhydride and a subsequent two-step chromatographic purification. A molecular mass determination of the Mtr complex by laser induced liquid bead ion desorption mass spectrometry (LILBID-MS) and size exclusion chromatography coupled with multi-angle light scattering (SEC-MALS) resulted in a (MtrABCDEFG)3 heterotrimeric complex of ca. 430 kDa with both techniques. Taking into account that the membrane protein complex contains various firmly bound small molecules, predominantly detergent molecules, the stoichiometry of the subunits is most likely 1:1. A schematic model for the subunit arrangement within the MtrABCDEFG protomer was deduced from the mass of Mtr subcomplexes obtained by harsh IR-laser LILBID-MS.
KW  - Methanogenesis
KW  - N5 -methyl-tetrahydromethanopterin: coenzyme M methyltransferase
KW  - Membrane protein complex
KW  - SEC-MALS
KW  - LILBID-MS
KW  - Dimethyl maleic anhydride
Y1  - 2016
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/44714
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-447143
SN  - 1879-2642
SN  - 0005-2736
N1  - Under an Elsevier user license
VL  - 1858
IS  - 9
SP  - 2140
EP  - 2144
PB  - Elsevier
CY  - Amsterdam
ER  -