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Expression and characterization of the FXYD ion transport regulators for NMR structural studies in lipid micelles and lipid bilayers.

ABSTRACT: The proteins PLM (phospholemman), CHIF (channel inducing factor), and Mat8 (mammary tumor protein 8 kDa) are members of the FXYD family of ion transport regulatory membrane proteins. Here we describe their cloning and expression in Escherichia coli, and their purification for NMR structural studies in lipid micelles and lipid bilayers. The molecular masses of the purified recombinant FXYD proteins, determined from SDS-PAGE and from MALDI TOF mass spectrometry, reflect monomeric species. The solution NMR and CD spectra in SDS micelles show that they adopt helical conformations. The solid-state NMR spectra in lipid bilayers give the first view of their transmembrane architecture.

SUBMITTER: Crowell KJ

PROVIDER: S-EPMC2917601 | biostudies-other | 2003 Jan

REPOSITORIES: biostudies-other

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Expression and characterization of the FXYD ion transport regulators for NMR structural studies in lipid micelles and lipid bilayers.

Crowell Kevin J KJ Franzin Carla M CM Koltay Anita A Lee Sangmin S Lucchese Anna Maria AM Snyder Bradley C BC Marassi Francesca M FM

Biochimica et biophysica acta 20030101 1

The proteins PLM (phospholemman), CHIF (channel inducing factor), and Mat8 (mammary tumor protein 8 kDa) are members of the FXYD family of ion transport regulatory membrane proteins. Here we describe their cloning and expression in Escherichia coli, and their purification for NMR structural studies in lipid micelles and lipid bilayers. The molecular masses of the purified recombinant FXYD proteins, determined from SDS-PAGE and from MALDI TOF mass spectrometry, reflect monomeric species. The solu ...[more]

PMID: 12535606

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