Structural highlights
Function[UBA1_YEAST] Activates ubiquitin by first adenylating its C-terminal glycine residue with ATP, and thereafter linking this residue to the side chain of a cysteine residue in E1, yielding an ubiquitin-E1 thioester and free AMP. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedUbiquitin (Ub) and ubiquitin-like proteins (Ubls) are conjugated to their targets by specific cascades involving three classes of enzymes, E1, E2, and E3. Each E1 adenylates the C terminus of its cognate Ubl, forms a E1 approximately Ubl thioester intermediate, and ultimately generates a thioester-linked E2 approximately Ubl product. We have determined the crystal structure of yeast Uba1, revealing a modular architecture with individual domains primarily mediating these specific activities. The negatively charged C-terminal ubiquitin-fold domain (UFD) is primed for binding of E2s and recognizes their positively charged first alpha helix via electrostatic interactions. In addition, a mobile loop from the domain harboring the E1 catalytic cysteine contributes to E2 binding. Significant, experimentally observed motions in the UFD around a hinge in the linker connecting this domain to the rest of the enzyme suggest a conformation-dependent mechanism for the transthioesterification function of Uba1; however, this mechanism clearly differs from that of other E1 enzymes. Structural insights into E1-catalyzed ubiquitin activation and transfer to conjugating enzymes.,Lee I, Schindelin H Cell. 2008 Jul 25;134(2):268-78. PMID:18662542[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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