Structural Similarity of a Membrane Protein in Micelles and Membranes
Sanford-Burnham Medical Research Institute, لا هویا, California, United StatesJournal of the American Chemical Society (Impact Factor: 12.11). 08/2007; 129(26):8078-9. DOI: 10.1021/ja0728371
The anisotropic spin interactions measured for membrane proteins in weakly oriented micelles and in oriented lipid bilayers provide independent and potentially complementary high-resolution restraints for structure determination. Here we show that the membrane protein CHIF adopts a similar structure in lipid micelles and bilayers, allowing the restraints from micelle and bilayer samples to be combined in a complementary fashion to enhance the structural information. Back-calculation and assignment of the NMR spectrum of CHIF in oriented lipid bilayers, from the structure determined in micelles, provides additional restraints for structure determination as well as the global orientation of the protein in the membrane. The combined use of solution and solid-state NMR restraints also affords cross-validation for the structural analysis.
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Article: Structural Similarity of a Membrane Protein in Micelles and Membranes
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- "e l s e v i e r . c o m / l o c a t e / b b a m e m experiments have shown that native protein quaternary structure may be maintained in detergent environments  ; aspects of secondary and tertiary structure may be similar in lipid bilayer versus micelle environments ; and the overall fold of a protein may persist in detergents . We have recently observed that the interaction of designed TM segments with detergents is highly sequencedependent , and in many cases mimics the predicted in vivo formation of both helix–helix and protein–lipid interactions  . "
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