1z7l
From Proteopedia
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Crystal structure of fragment of mouse ubiquitin-activating enzyme
Overview
Protein ubiquitination requires the sequential activity of three enzymes:, a ubiquitin-activating enzyme (E1), a ubiquitin-conjugating enzyme (E2), and a ubiquitin-ligase (E3). The ubiquitin-transfer machinery is, hierarchically organized; for every ubiquitin-activating enzyme, there are, several ubiquitin-conjugating enzymes, and most ubiquitin-conjugating, enzymes can in turn interact with multiple ubiquitin ligases. Despite the, central role of ubiquitin-activating enzyme in this cascade, a crystal, structure of a ubiquitin-activating enzyme is not available. The enzyme is, thought to consist of an adenylation domain, a catalytic cysteine domain, a four-helix bundle, and possibly, a ubiquitin-like domain. Its, adenylation domain can be modeled because it is clearly homologous to the, structurally known adenylation domains of the activating enzymes for the, small ubiquitin-like modifier (SUMO) and for the protein encoded by the, neuronal precursor cell-expressed, developmentally down-regulated gene 8, (NEDD8). Low sequence similarity and vastly different domain lengths make, modeling difficult for the catalytic cysteine domain that results from the, juxtaposition of two catalytic cysteine half-domains. Here, we present a, biochemical and crystallographic characterization of the two half-domains, and the crystal structure of the larger, second catalytic cysteine, half-domain of mouse ubiquitin-activating enzyme. We show that the domain, is organized around a conserved folding motif that is also present in the, NEDD8- and SUMO-activating enzymes, and we propose a tentative model for, full-length ubiquitin-activating enzyme.
About this Structure
1Z7L is a Single protein structure of sequence from Mus musculus with TBR as ligand. Full crystallographic information is available from OCA.
Reference
Crystal structure of a fragment of mouse ubiquitin-activating enzyme., Szczepanowski RH, Filipek R, Bochtler M, J Biol Chem. 2005 Jun 10;280(23):22006-11. Epub 2005 Mar 16. PMID:15774460
Page seeded by OCA on Wed Nov 21 07:17:02 2007
