6533b82cfe1ef96bd1290173

RESEARCH PRODUCT

A Ser residue influences the structure and stability of a Pro-kinked transmembrane helix dimer

Daniel E. OtzenDirk SchneiderMathias WeberLydia Tome

subject

Models MolecularProlineHeme bindingStereochemistryDimerMolecular ConformationBiophysicsCofactor bindingHemeBiochemistryProtein Structure Secondarychemistry.chemical_compoundProtein structureProtein stabilitySerineProtein foldingCofactor bindingHydrogen bondCell MembranePhotosystem II Protein ComplexHydrogen BondingCell BiologyCytochrome b GroupTransmembrane proteinProtein Structure TertiaryOxygenTransmembrane domainHelix interactionchemistrySpectrophotometryMembrane proteinMutationTransmembrane helixProtein foldingDimerizationProtein Binding

description

AbstractWhen localized adjacent to a Pro-kink, Thr and Ser residues can form hydrogen bonds between their polar hydroxyl group and a backbone carbonyl oxygen and thereby modulate the actual bending angle of a distorted transmembrane α-helix. We have used the homo-dimeric transmembrane cytochrome b559′ to analyze the potential role of a highly conserved Ser residue for assembly and stabilization of transmembrane proteins. Mutation of the conserved Ser residue to Ala resulted in altered heme binding properties and in increased stability of the holo-protein, most likely by tolerating subtle structural rearrangements upon heme binding. The results suggest a crucial impact of an intrahelical Ser hydrogen bond in defining the structure of a Pro-kinked transmembrane helix dimer.

yearjournalcountryeditionlanguage
2012-09-01Biochimica et Biophysica Acta (BBA) - Biomembranes
https://doi.org/10.1016/j.bbamem.2012.04.003