1as5

SOLUTION STRUCTURE OF CONOTOXIN Y-PIIIE FROM CONUS PURPURASCENS, NMR, 14 STRUCTURES

spinqualitylabelsall models 1as5 Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 1as5 is a 1 chain structure with sequence from Conus purpurascens. Full experimental information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: Solution NMR Ligands: HYP, NH2 Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function CM3E_CONPU Psi-conotoxins act on postsynaptic membranes, and act as non-competitive antagonist of nicotinic acetylcholine receptors (nAChR). Is more toxic than Psi-conotoxin PIIIF. Has paralytic activity when injected intraperitoneally into goldfish. Publication Abstract from PubMed The three-dimensional structure of conotoxin psi-PIIIE, a 24-amino acid peptide from Conus purpurascens, has been solved using two-dimensional (2D) 1H NMR spectroscopy. Conotoxin psi-PIIIE contains the same disulfide bonding pattern as the mu-conotoxins, which target skeletal muscle sodium channels, but has been shown to antagonize the acetylcholine gated cation channel through a noncompetitive mechanism. Structural information was obtained by the analysis of a series of 2D NOESY spectra as well as measurement of coupling constants from 1D 1H and PE-COSY NMR experiments. Molecular modeling calculations included the use of the distance geometry (DG) algorithm, simulated annealing techniques, and the restrained molecular dynamics method. The resulting structures are considerably similar to the previously published structures for the mu-conotoxins GIIIA and GIIIB, despite the lack of sequence conservation between conotoxin psi-PIIIE and the mu-conotoxins. The structure consists of a series of tight turns, each turn occurring in the position analogous to those of turns described in mu-GIIIA and mu-GIIIB. This suggests the disulfide bonding pattern is able to largely direct the structure of the peptides, creating a stable structural motif which allows extensive sequence substitution of non-cystine residues. Three-dimensional solution structure of conotoxin psi-PIIIE, an acetylcholine gated ion channel antagonist.,Mitchell SS, Shon KJ, Foster MP, Davis DR, Olivera BM, Ireland CM Biochemistry. 1998 Feb 3;37(5):1215-20. PMID:9477946 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

Proteopedia Page Contributors and Editors (what is this?)

OCA