title: Solution structure of lysine-free (K0) ubiquitin.
abstract: Lysine-free ubiquitin (K0-Ub) is commonly used to study the ubiquitin-signaling pathway, where it is assumed to have the same structure and function as wild-type ubiquitin (wt-Ub). However, the K0-Ub (15) N heteronuclear single quantum correlation NMR spectrum differs significantly from wt-Ub and the melting temperature is depressed by 19°C, raising the question of the structural integrity and equivalence to wt-Ub. The three-dimensional structure of K0-Ub was determined by solution NMR, using chemical shift and residual dipolar coupling data. K0-Ub adopts the same backbone structure as wt-Ub, and all significant chemical shifts can be related to interactions impacted by the K to R mutations.
authors.affiliation: Structural Biophysics Laboratory, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, 21702.
authors.forename: Tao
authors.initials: T
authors.lastname: Huang
authors.forename: Jess
authors.initials: J
authors.lastname: Li
authors.forename: R Andrew
authors.initials: RA
authors.lastname: Byrd
mesh_terms: D006801:Humans; D008239:Lysine / Q000737:chemistry*; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D011487:Protein Conformation; D055550:Protein Stability; D025801:Ubiquitin / Q000737:chemistry*
chemical_list: D025801:Ubiquitin; D008239:Lysine
keywords: CS-Rosetta; K0-Ub; NMR; ubiquitin