A transmembrane helix dimer: structure and implications.

K R MacKenzie; J H Prestegard; D M Engelman

doi:10.1126/science.276.5309.131

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PubMed · 9082985

A transmembrane helix dimer: structure and implications.

K R MacKenzie·J H Prestegard·D M Engelman

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Abstract

The three-dimensional structure of the dimeric transmembrane domain of glycophorin A (GpA) was determined by solution nuclear magnetic resonance spectroscopy of a 40-residue peptide solubilized in aqueous detergent micelles. The GpA membrane-spanning alpha helices cross at an angle of -40 degrees and form a small but well-packed interface that lacks intermonomer hydrogen bonds. The structure provides an explanation for the previously characterized sequence dependence of GpA dimerization and demonstrates that van der Waals interactions alone can mediate stable and specific associations between transmembrane helices.

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Amino Acid Sequence Dimerization Erythrocyte Membrane Glycine Glycophorins Hydrogen Bonding Magnetic Resonance Spectroscopy Micelles Models, Molecular Molecular Sequence Data Mutagenesis Protein Conformation Protein Folding Protein Structure, Secondary Recombinant Fusion Proteins Journal Article Research Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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K R MacKenzie, J H Prestegard, D M Engelman. 1997-04-04. A transmembrane helix dimer: structure and implications.. https://doi.org/10.1126/science.276.5309.131

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