2ax5 | pdb_00002ax5
Solution Structure of Urm1 from Saccharomyces Cerevisiae
Structural highlights
Function[URM1_YEAST] Acts as a sulfur carrier required for 2-thiolation of mcm(5)S(2)U at tRNA wobble positions. Serves as sulfur donor in tRNA 2-thiolation reaction by being thiocarboxylated (-COSH) at its C-terminus by UBA4. The sulfur is then transferred to tRNA to form 2-thiolation of mcm(5)S(2)U. Prior mcm(5) tRNA modification by the elongator complex is required for 2-thiolation. May also act as an ubiquitin-like protein that is covalently conjugated to other proteins such as AHP1; the relevance of such function is however unclear in vivo. Indirectly involved in oxidative stress response and regulation of budding and haploid invasive growth.[1] [2] [3] [4] [5] [6] [7] 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 PubMedProtein modifiers are involved in diverse biological processes and regulate the activity or function of target proteins by covalently conjugating to them. Although ubiquitin and a number of ubiquitin-like protein modifiers (Ubls) in eukaryotes have been identified, no protein modifier has been found in prokaryotes; thus, their evolutionary origin remains a puzzle. To infer the evolutionary relationships between the protein modifiers and sulfur carrier proteins, we solved the solution NMR structure of the Urm1 (ubiquitin-related modifier-1) protein from Saccharomyces cerevisiae. Both structural comparison and phylogenetic analysis of the ubiquitin superfamily, with emphasis on the Urm1 family, indicate that Urm1 is the unique "molecular fossil" that has the most conserved structural and sequence features of the common ancestor of the entire superfamily. The similarities of 3D structure and hydrophobic and electrostatic surface features between Urm1 and MoaD (molybdopterin synthase small subunit) suggest that they may interact with partners in a similar manner, and similarities between Urm1-Uba4 and MoaD-MoeB establish an evolutionary link between ATP-dependent protein conjugation in eukaryotes and ATP-dependent cofactor sulfuration. Solution structure of Urm1 and its implications for the origin of protein modifiers.,Xu J, Zhang J, Wang L, Zhou J, Huang H, Wu J, Zhong Y, Shi Y Proc Natl Acad Sci U S A. 2006 Aug 1;103(31):11625-30. Epub 2006 Jul 24. PMID:16864801[8] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
| ||||||||||||||||||
