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Production, Crystallization and Structure Determination of C. difficile PPEP-1 via Microseeding and Zinc-SAD
Published on: December 30, 2016
The solution structure of the PufX polypeptide from Rhodobacter sphaeroides
Richard B Tunnicliffe1, Emma C Ratcliffe, C Neil Hunter
1Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK.
Abstract:
PufX organizes the photosynthetic reaction centre-light harvesting complex 1 (RC-LH1) core complex of Rhodobacter sphaeroides and facilitates quinol/quinone exchange between the RC and cytochrome bc(1) complexes. The structure of PufX in organic solvent reveals two hydrophobic helices flanked by unstructured termini and connected by a helical bend. The proposed location of basic residues and tryptophans at the membrane interface orients the C-terminal helix along the membrane normal, with the GXXXG motifs in positions unsuitable as direct drivers of dimerisation of the RC-LH1 complex. The N-terminal helix is predicted to extend approximately 40 Anggstrom along the membrane interface.
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