Conformational heterogeneity in polypeptide cardiac stimulants from sea anemones

FEBS Letters

Blunt, John W.¹  Gooley, Paul R.¹  Norton, Raymond S.¹ 

[1] School of Biochemistry, University of New South Wales, PO Box 1, Kensington, NSW 2033, Australia

关键词: Cardiotonic agent;    Neurotoxin;    Peptide conformation;    1H-NMR;    Proline;    pH titration;    AP-A;    anthoplurin-A;    ATX I;    Anemonia sulcata toxin I;    ATX II;    Anemonia sulcata toxin II;    DSS;    4;    4-dimethyl-4-silapentane-1-sulfonate;    COSY;    2-dimensional homonuclear correlated spectroscopy;   

DOI  :  10.1016/0014-5793(84)81068-6

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

High-resolution ¹H NMR spectra at 300 MHz of the polypeptide cardiac stimulants anthopIeurin-A and Anemonia sulcata toxin II reveal conformational heterogeneity in both molecules. The two conformations, manifest in a number of split ¹H resonances, are in slow exchange over a wide range of pH and temperature. Heterogeneity affects a region of these molecules containing the structurally and functionally important Asp residues. By comparison with a homologous polypeptide Anemonia sulcata toxin I, which does not show this type of heterogeneity, it is suggested that the heterogeneity may originate in cis-trans isomerism of the Gly-40 to Pro-41 peptide bond.

【 授权许可】

Unknown