1tlu
From Proteopedia
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Crystal Structure of Thermotoga maritima S-adenosylmethionine decarboxylase
Overview
S-adenosylmethionine decarboxylase (AdoMetDC) is a critical regulatory, enzyme of the polyamine biosynthetic pathway and belongs to a small class, of pyruvoyl-dependent amino acid decarboxylases. Structural elucidation of, the prokaryotic AdoMetDC is of substantial interest in order to determine, the relationship between the eukaryotic and prokaryotic forms of the, enzyme. Although both forms utilize pyruvoyl groups, there is no, detectable sequence similarity except at the site of pyruvoyl group, formation. The x-ray structure of the Thermatoga maritima AdoMetDC, proenzyme reveals a dimeric protein fold that is remarkably similar to the, eukaryotic AdoMetDC protomer, suggesting an evolutionary link between the, two forms of the enzyme. Three key active site residues (Ser55, His68, and, Cys83) involved in substrate binding, catalysis or proenzyme processing, that were identified in the human and potato AdoMet-DCs are structurally, conserved in the T. maritima AdoMetDC despite very limited primary, sequence identity. The role of Ser55, His68, and Cys83 in the, self-processing reaction was investigated through site-directed, mutagenesis. A homology model for the Escherichia coli AdoMetDC was, generated based on the structures of the T. maritima and human AdoMetDCs.
About this Structure
1TLU is a Single protein structure of sequence from Thermotoga maritima. Active as Adenosylmethionine decarboxylase, with EC number 4.1.1.50 Full crystallographic information is available from OCA.
Reference
Evolutionary links as revealed by the structure of Thermotoga maritima S-adenosylmethionine decarboxylase., Toms AV, Kinsland C, McCloskey DE, Pegg AE, Ealick SE, J Biol Chem. 2004 Aug 6;279(32):33837-46. Epub 2004 May 18. PMID:15150268
Page seeded by OCA on Wed Nov 21 03:23:27 2007
