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Comparison of "Polarization inversion with spin exchange at magic angle" and "geometric analysis of labeled alanines" methods for transmembrane helix alignment.

ABSTRACT: Using the model alpha-helical peptide acetyl-GGALW5LALALALALALALW19LAGA-ethanolamide ("GWALP23"), we have compared the polarization inversion with spin exchange at magic angle method and geometric analysis of labeled alanines method for estimating the transmembrane helix orientation. For GWALP23 in bilayers of a short lipid, dilauroylphosphatidylcholine, we find general agreement between the two methods, with a static helix tilt of about 11degrees-13degrees with respect to the bilayer normal.

SUBMITTER: Vostrikov VV

PROVIDER: S-EPMC2609751 | biostudies-literature | 2008 Sep

REPOSITORIES: biostudies-literature

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Comparison of "Polarization inversion with spin exchange at magic angle" and "geometric analysis of labeled alanines" methods for transmembrane helix alignment.

Vostrikov Vitaly V VV Grant Christopher V CV Daily Anna E AE Opella Stanley J SJ Koeppe Roger E RE

Journal of the American Chemical Society 20080903 38

Using the model alpha-helical peptide acetyl-GGALW5LALALALALALALW19LAGA-ethanolamide ("GWALP23"), we have compared the polarization inversion with spin exchange at magic angle method and geometric analysis of labeled alanines method for estimating the transmembrane helix orientation. For GWALP23 in bilayers of a short lipid, dilauroylphosphatidylcholine, we find general agreement between the two methods, with a static helix tilt of about 11degrees-13degrees with respect to the bilayer normal. ...[more]

PMID: 18763771

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