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An Adaptable Phospholipid Membrane Mimetic System for Solution NMR Studies of Membrane Proteins.

ABSTRACT: Based on the saposin-A (SapA) scaffold protein, we demonstrate the suitability of a size-adaptable phospholipid membrane-mimetic system for solution NMR studies of membrane proteins (MPs) under close-to-native conditions. The Salipro nanoparticle size can be tuned over a wide pH range by adjusting the saposin-to-lipid stoichiometry, enabling maintenance of sufficiently high amounts of phospholipid in the Salipro nanoparticle to mimic a realistic membrane environment while controlling the overall size to enable solution NMR for a range of MPs. Three representative MPs, including one G-protein-coupled receptor, were successfully incorporated into SapA-dimyristoylphosphatidylcholine nanoparticles and studied by solution NMR spectroscopy.

SUBMITTER: Chien CH

PROVIDER: S-EPMC6109379 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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An Adaptable Phospholipid Membrane Mimetic System for Solution NMR Studies of Membrane Proteins.

Chien Chih-Ta Henry CH Helfinger Lukas R LR Bostock Mark J MJ Solt Andras A Tan Yi Lei YL Nietlispach Daniel D

Journal of the American Chemical Society 20171010 42

Based on the saposin-A (SapA) scaffold protein, we demonstrate the suitability of a size-adaptable phospholipid membrane-mimetic system for solution NMR studies of membrane proteins (MPs) under close-to-native conditions. The Salipro nanoparticle size can be tuned over a wide pH range by adjusting the saposin-to-lipid stoichiometry, enabling maintenance of sufficiently high amounts of phospholipid in the Salipro nanoparticle to mimic a realistic membrane environment while controlling the overall ...[more]

PMID: 28990386

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