4NNJ

Crystal structure of Uba1 in complex with ubiquitin-AMP and thioesterified ubiquitin

Summary for 4NNJ

• Entry DOI: 10.2210/pdb4nnj/pdb
• Descriptor: Ubiquitin-activating enzyme E1 1, Uba1, SULFATE ION, ... (6 entities in total)
• Functional Keywords: ubiquitin activating enzyme (e1), uba1, ubiquitin, acyladenylate, ubiquitin thioester, ubiquitin activation, amp, thioesterified ub, protein binding
• Biological source: Saccharomyces cerevisiae (Baker's yeast); More
• Cellular location: Cytoplasm: P22515; Cytoplasm (By similarity): P0CG63
• Total number of polymer chains: 5
• Total formula weight: 262753.25

Authors

Schaefer, A.,Schindelin, H. (deposition date: 2013-11-18, release date: 2014-05-07, Last modification date: 2024-10-16)

Primary citation

Schafer, A.,Kuhn, M.,Schindelin, H.
Structure of the ubiquitin-activating enzyme loaded with two ubiquitin molecules.
Acta Crystallogr.,Sect.D, 70:1311-1320, 2014

PubMed Abstract: The activation of ubiquitin by the ubiquitin-activating enzyme Uba1 (E1) constitutes the first step in the covalent modification of target proteins with ubiquitin. This activation is a three-step process in which ubiquitin is adenylated at its C-terminal glycine, followed by the covalent attachment of ubiquitin to a catalytic cysteine residue of Uba1 and the subsequent adenylation of a second ubiquitin. Here, a ubiquitin E1 structure loaded with two ubiquitin molecules is presented for the first time. While one ubiquitin is bound in its adenylated form to the active adenylation domain of E1, the second ubiquitin represents the status after transfer and is covalently linked to the active-site cysteine. The covalently linked ubiquitin enables binding of the E2 enzyme without further modification of the ternary Uba1-ubiquitin2 arrangement. This doubly loaded E1 structure constitutes a missing link in the structural analysis of the ubiquitin-transfer cascade.

PubMed: 24816100
DOI: 10.1107/S1399004714002910

Experimental method

X-RAY DIFFRACTION (2.4 Å)