The electronic structure and dipole moment of charybdotoxin, a scorpion venom peptide with K channel blocking activity - Quantitative Biology > BiomoleculesReport as inadecuate




The electronic structure and dipole moment of charybdotoxin, a scorpion venom peptide with K channel blocking activity - Quantitative Biology > Biomolecules - Download this document for free, or read online. Document in PDF available to download.

Abstract: The electronic structure of charybdotoxin ChTX, a scorpion venom peptidethat is known to act as a potassium channel blocker, is investigated with theaid of quantum mechanical calculations. The dipole moment vector 145 D ofChTX can be stirred by the full length KcsA potassium channel-s macrodipole403 D thereby assuming the proper orientation before binding the ion channelon the cell surface. The localization of the frontier orbitals of ChTX has beenrevealed for the first time. HOMO is localized on Trp14 while the threelowest-energy MOs LUMO, LUMO+1, and LUMO+2 are localized on the threedisulfide bonds that characterize this pepetide. An effective way to engineerthe HOMO-LUMO H-L gap of ChTX is that of replacing its Trp14 residue withAla14 whereas deletion of the LUMO-associated disulfide bond with the insertionof a pair of L-alpha-aminobutyric acid residues does not affect the H-L energygap.



Author: Fabio Pichierri

Source: https://arxiv.org/



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