Crystallizing Transmembrane Peptides in Lipidic Mesophases

Membrane Structural and Functional Biology Group, School of Biochemistry and Immunology, and School of Medicine, Trinity College, Dublin, Ireland.
Biophysical Journal (Impact Factor: 3.83). 08/2010; 99(3):L23-5. DOI: 10.1016/j.bpj.2010.05.011
Source: PubMed

ABSTRACT Structure determination of membrane proteins by crystallographic means has been facilitated by crystallization in lipidic mesophases. It has been suggested, however, that this so-called in meso method, as originally implemented, would not apply to small protein targets having </=4 transmembrane crossings. In our study, the hypothesis that the inherent flexibility of the mesophase would enable crystallogenesis of small proteins was tested using a transmembrane pentadecapeptide, linear gramicidin, which produced structure-grade crystals. This result suggests that the in meso method should be considered as a viable means for high-resolution structure determination of integral membrane peptides, many of which are predicted to be coded for in the human genome.

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