1l2q
From Proteopedia
Crystal Structure of the Methanosarcina barkeri Monomethylamine Methyltransferase (MtmB)
Overview
Genes encoding methanogenic methylamine methyltransferases all contain an in-frame amber (UAG) codon that is read through during translation. We have identified the UAG-encoded residue in a 1.55 angstrom resolution structure of the Methanosarcina barkeri monomethylamine methyltransferase (MtmB). This structure reveals a homohexamer comprised of individual subunits with a TIM barrel fold. The electron density for the UAG-encoded residue is distinct from any of the 21 natural amino acids. Instead it appears consistent with a lysine in amide-linkage to (4R,5R)-4-substituted-pyrroline-5-carboxylate. We suggest that this amino acid be named l-pyrrolysine.
About this Structure
1L2Q is a Single protein structure of sequence from Methanosarcina barkeri. Full crystallographic information is available from OCA.
Reference
A new UAG-encoded residue in the structure of a methanogen methyltransferase., Hao B, Gong W, Ferguson TK, James CM, Krzycki JA, Chan MK, Science. 2002 May 24;296(5572):1462-6. PMID:12029132 Page seeded by OCA on Fri May 2 23:28:29 2008
