1BHJ

CRYSTAL STRUCTURE OF APO-GLYCINE N-METHYLTRANSFERASE (GNMT)

Summary for 1BHJ

• Entry DOI: 10.2210/pdb1bhj/pdb
• Descriptor: GLYCINE N-METHYLTRANSFERASE (2 entities in total)
• Functional Keywords: methyltransferase, folate binding protein
• Biological source: Rattus norvegicus (Norway rat)
• Cellular location: Cytoplasm: P13255
• Total number of polymer chains: 2
• Total formula weight: 64921.66

Authors

Pattanayek, R.,Newcomer, M.E.,Wagner, C. (deposition date: 1998-06-09, release date: 1999-01-06, Last modification date: 2024-05-22)

Primary citation

Pattanayek, R.,Newcomer, M.E.,Wagner, C.
Crystal structure of apo-glycine N-methyltransferase (GNMT).
Protein Sci., 7:1326-1331, 1998

PubMed Abstract: The crystal structure of the recombinant apo-form of glycine N-methyltransferase (GNMT) has been determined at 2.5 A resolution. GNMT is a tetrameric enzyme (monomer Mr = 32,423Da, 292 amino acids) that catalyzes the transfer of a methyl group from S-adenosylmethionine (AdoMet) to glycine with the formation of S-adenosylhomocysteine (AdoHcy) and sarcosine (N-methylglycine). GNMT is a regulatory enzyme, which is inhibited by 5-methyltetrahydrofolate pentaglutamate and believed to control the ratio of AdoMet to AdoHcy in tissues. The crystals belong to the orthorhombic space group P2(1)2(1)2 (a = 85.39, b = 174.21, c = 44.71 A) and contain one dimer per asymmetric unit. The AdoMet-GNMT structure served as the starting model. The structure was refined to an R-factor of 21.9%. Each monomer is a three-domain structure with a large cavity enclosed by the three domains. The tetramer resembles a square with a central channel about which N-terminal domains are intertwined. Only localized changes of the residues involved in the binding pocket are observed for the apo-GNMT structure when compared to that determined in the presence of substrate and substrate analog.

PubMed: 9655336

Experimental method

X-RAY DIFFRACTION (2.5 Å)