1xyd | pdb_00001xyd

NMR Solution Structure of Rat Zinc-Calcium-S100B, 20 Structures

spinqualitylabelsall models 1xyd, 20 NMR models Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 1xyd is a 2 chain structure with sequence from Rattus norvegicus. Full experimental information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: CA, ZN Related: 1qlk, 1b4c, 1dt7, 1mwn, 3psr, 1odb Gene: S100b (Rattus norvegicus) Resources: FirstGlance, OCA, RCSB, PDBsum 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 PubMed The EF-hand calcium-binding protein S100B also binds one zinc ion per subunit with a relatively high affinity (K(d) approximately 90 nM) [Wilder et al., (2003) Biochemistry 42, 13410-13421]. In this study, the structural characterization of zinc binding to calcium-loaded S100B was examined using high-resolution NMR techniques, including structural characterization of this complex in solution at atomic resolution. As with other S100 protein structures, the quaternary structure of Zn(2+)-Ca(2+)-bound S100B was found to be dimeric with helices H1, H1', H4, and H4' forming an X-type four-helix bundle at the dimer interface. NMR data together with mutational analyses are consistent with Zn(2+) coordination arising from His-15 and His-25 of one S100B subunit and from His-85 and Glu-89 of the other subunit. The addition of Zn(2+) was also found to extend helices H4 and H4' three to four residues similar to what was previously observed with the binding of target proteins to S100B. Furthermore, a kink in helix 4 was observed in Zn(2+)-Ca(2+)-bound S100B that is not in Ca(2+)-bound S100B. These structural changes upon Zn(2+)-binding could explain the 5-fold increase in affinity that Zn(2+)-Ca(2+)-bound S100B has for peptide targets such as the TRTK peptide versus Ca(2+)-bound S100B. There are also changes in the relative positioning of the two EF-hand calcium-binding domains and the respective helices comprising these EF-hands. Changes in conformation such as these could contribute to the order of magnitude higher affinity that S100B has for calcium in the presence of Zn(2+). Solution structure of zinc- and calcium-bound rat S100B as determined by nuclear magnetic resonance spectroscopy.,Wilder PT, Varney KM, Weiss MB, Gitti RK, Weber DJ Biochemistry. 2005 Apr 19;44(15):5690-702. PMID:15823027 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also S100 protein

Proteopedia Page Contributors and Editors (what is this?)

OCA