Orientation of TOAC amino-acid spin labels in alpha-helices and beta-strands

Journal of Magnetic Resonance
D Marsh

Abstract

The orientation of alpha-helices or beta-strands, e.g., in membranes, can be determined from EPR order parameters of (2,2,6,6-tetramethyl-piperidine-1-oxy-4-amino-4-carboxylic acid) TOAC amino-acid spin labels incorporated in the polypeptide backbone. This requires knowledge of the inclination of the nitroxide axes, relative to the alpha-helix or beta-strand axis. Crystal structures of TOAC-containing peptides are used to derive the spin-label orientation relative to refined alpha-poly-l-alanine and beta-poly-l-alanine structures. The spin-label z-axes of the two mirror-image TOAC twist-boat conformers are inclined at 13+/-2 degrees and 65+/-3 degrees , respectively, to the alpha-helix axis, or at 25+/-3 degrees and 32+/-3 degrees to the beta-strand axis.

References

Nov 28, 1967·Journal of Molecular Biology·S Arnott, S D Dover
Jan 12, 1983·Biochimica Et Biophysica Acta·C R NakaieA C Paiva
Sep 28, 2004·Proceedings of the National Academy of Sciences of the United States of America·Christine B KarimDavid D Thomas
May 12, 2005·The Journal of Peptide Research : Official Journal of the American Peptide Society·M CrismaC Toniolo

❮ Previous
Next ❯

Citations

Jun 19, 2008·Journal of Biomolecular NMR·Hanna E LindforsMarcellus Ubbink
May 9, 2007·FEBS Letters·Luis Gustavo de Deus TeixeiraClovis Ryuichi Nakaie
Oct 24, 2006·Biophysical Journal·Derek MarshClaudio Toniolo
Jun 26, 2007·Chemistry & Biodiversity·Derek MarshClaudio Toniolo
Sep 6, 2011·Physical Chemistry Chemical Physics : PCCP·Ya-Wen Huang, Yun-Wei Chiang
Sep 8, 2011·Angewandte Chemie·Sven StollerUlf Diederichsen
Jan 26, 2018·Applied Magnetic Resonance·Derek Marsh
Nov 7, 2019·The Journal of Physical Chemistry. B·Peter D MartinStefan Stoll

❮ Previous
Next ❯

Related Concepts

Related Feeds

Antifungals (ASM)

An antifungal, also known as an antimycotic medication, is a pharmaceutical fungicide or fungistatic used to treat and prevent mycosis such as athlete's foot, ringworm, candidiasis, cryptococcal meningitis, and others. Discover the latest research on antifungals here.

Antifungals

An antifungal, also known as an antimycotic medication, is a pharmaceutical fungicide or fungistatic used to treat and prevent mycosis such as athlete's foot, ringworm, candidiasis, cryptococcal meningitis, and others. Discover the latest research on antifungals here.