title: Improved low pH bicelle system for orienting macromolecules over a wide temperature range.
abstract: We have prepared and characterized a novel bicelle system composed of 1,2-di-O-dodecyl-sn-glycero-3-phosphocholine (DIODPC) and 3-(chloramidopropyl)dimethylammonio-2-hydroxyl-1-propane sulfonate (CHAPSO). At the optimal DIODPC/CHAPSO molar ratio of 4.3:1, this medium becomes magnetically oriented from pH 6.5 down to pH 1.0. Unlike previously reported bicelle preparations, these bicelles are chemically stable at low pH and are capable of inducing protein alignment, as illustrated by the large residual dipolar couplings measured for rusticyanin from Thiobacillus ferrooxidans at pH 2.1. The DIODPC/CHAPSO system is particularly useful for measuring residual dipolar couplings of macromolecules that require very acidic conditions.
authors.affiliation: Department of Molecular Biology MB-2, Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: S
authors.initials: S
authors.lastname: Cavagnero
authors.forename: H J
authors.initials: HJ
authors.lastname: Dyson
authors.forename: P E
authors.initials: PE
authors.lastname: Wright
mesh_terms: D000595:Amino Acid Sequence; D001400:Azurin / Q000031:analogs & derivatives* / Q000737:chemistry; D001426:Bacterial Proteins / Q000737:chemistry*; D002793:Cholic Acids; D003902:Detergents; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000379:methods; D010713:Phosphatidylcholines; D011487:Protein Conformation; D013696:Temperature; D013816:Thermodynamics; D013855:Thiobacillus
chemical_list: D001426:Bacterial Proteins; D002793:Cholic Acids; D003902:Detergents; D007202:Indicators and Reagents; D010713:Phosphatidylcholines; C012543:rusticyanin; D001400:Azurin; C048531:chapso