2JMY

Solution structure of CM15 in DPC micelles

Summary for 2JMY

• Entry DOI: 10.2210/pdb2jmy/pdb
• NMR Information: BMRB: 15099
• Descriptor: CM15 (1 entity in total)
• Functional Keywords: antimicrobial, dpc micelle, antimicrobial protein
• Biological source: synthetic construct
• Total number of polymer chains: 1
• Total formula weight: 1776.32

Authors

Respondek, M.,Madl, T.,Goebl, C.,Golser, R.,Zangger, K. (deposition date: 2006-12-13, release date: 2007-07-17, Last modification date: 2024-05-08)

Primary citation

Respondek, M.,Madl, T.,Gobl, C.,Golser, R.,Zangger, K.
Mapping the orientation of helices in micelle-bound peptides by paramagnetic relaxation waves
J.Am.Chem.Soc., 129:5228-5234, 2007

PubMed Abstract: Many antimicrobial peptides form alpha-helices when bound to a membrane. In addition, around 80% of residues in membrane-bound proteins are found in alpha-helical regions. The orientation and location of such helical peptides and proteins in the membrane are key factors determining their function and activity. Here we present a new solution state NMR method for obtaining the orientation of helical peptides in a membrane-mimetic environment (micelle-bound) without any chemical perturbation of the peptide-micelle system. By monitoring proton longitudinal relaxation rates upon addition of the freely water-soluble and inert paramagnetic probe Gd(DTPA-BMA) to an alpha-helical peptide, a wavelike pattern with a periodicity of 3.6 residues per turn is observed. The tilt and azimuth (rotation) angle of the helix determine the shape of this paramagnetic relaxation wave and can be obtained by least-square fitting of measured relaxation enhancements. Results are presented for the 15-residue antimicrobial peptide CM15 which forms an amphipathic helix almost parallel to the surface of the micelle. Thus, a few fast experiments enable the identification of helical regions and determination of the helix orientation within the micelle without the need for covalent modification, isotopic labeling, or sophisticated equipment. This approach opens a path toward the topology determination of alpha-helical membrane-proteins without the need for a complete NOE-based structure determination.

PubMed: 17397158
DOI: 10.1021/ja069004f

Experimental method

SOLUTION NMR