5i5a | pdb_00005i5a

quasi racemic structure of allo-Ile7-ShK and D-ShK

spinqualitylabelsall models 5i5a, resolution 1.20Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 5i5a is a 2 chain structure with sequence from Stichodactyla helianthus and Synthetic construct. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 1.2Å Ligands: DAL, DAR, DAS, DCY, DGN, DHI, DIL, DLE, DLY, DPN, DPR, DSN, DTH, DTY, GOL, LI, MED, MLT, NA Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function K1A_STIHL Inhibits voltage-dependent potassium channels. Inhibits Kv1.3/KCNA3 potently and also blocks Kv1.1/KCNA1, Kv1.4/KCNA4, and Kv1.6/KCNA6 at subnanomolar concentrations. Publication Abstract from PubMed ShK toxin is a cysteine-rich 35-residue protein ion-channel ligand isolated from the sea anemone Stichodactyla helianthus. In this work, we studied the effect of inverting the side chain stereochemistry of individual Thr or Ile residues on the properties of the ShK protein. Molecular dynamics simulations were used to calculate the free energy cost of inverting the side-chain stereochemistry of individual Thr or Ile residues. Guided by the computational results, we used chemical protein synthesis to prepare three ShK polypeptide chain analogues, each containing either an allo-Thr or an allo-Ile residue. The three allo-Thr or allo-Ile-containing ShK polypeptides were able to fold into defined protein products, but with different folding propensities. Their relative thermal stabilities were measured and were consistent with the MD simulation data. Structures of the three ShK analogue proteins were determined by quasi-racemic X-ray crystallography and were similar to wild-type ShK. All three ShK analogues retained ion-channel blocking activity. Inversion of the Side-Chain Stereochemistry of Indvidual Thr or Ile Residues in a Protein Molecule: Impact on the Folding, Stability, and Structure of the ShK Toxin.,Dang B, Shen R, Kubota T, Mandal K, Bezanilla F, Roux B, Kent SB Angew Chem Int Ed Engl. 2017 Feb 14. doi: 10.1002/anie.201612398. PMID:28194851 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Potassium channel toxin 3D structures

Proteopedia Page Contributors and Editors (what is this?)

OCA