Taurocholate-induced dimerization of bovine cholesterol esterase in sodium dodecylsulfate.
Purified bovine cholesterol esterase (CE) showed one major band with an apparent molecular mass of 58 kDa on sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE). In the presence of taurocholate another major band with an apparent molecular mass of 116 kDa, corresponding to the dimer, appeared. Longer heating times and higher concentrations of CE in SDS-sample buffer increased the relative amount of the dimer. Higher SDS concentration in the sample buffer reduced the amount of dimer. Mercaptoethanol concentration had no effect. The dimer did not contain taurocholate and readily reverted to the monomer. It is concluded that taurocholate mediates the dimerization of CE in SDS by facilitating the formation of hydrophobic interactions between monomeric subunits.
Vakos
H T
HT
Department of Chemistry, University of Ottawa, Ontario, Canada.
Burton
G W
GW
Kaplan
H
H
D000818:Animals; D002417:Cattle; D002846:Chromatography, Affinity; D019281:Dimerization; D004591:Electrophoresis, Polyacrylamide Gel; D046911:Macromolecular Substances; D008970:Molecular Weight; D011994:Recombinant Proteins / Q000187:drug effects / Q000302:isolation & purification / Q000378:metabolism; D012967:Sodium Dodecyl Sulfate; D002787:Sterol Esterase / Q000737:chemistry* / Q000187:drug effects / Q000302:isolation & purification; D013656:Taurocholic Acid / Q000494:pharmacology*
D046911:Macromolecular Substances; D011994:Recombinant Proteins; D012967:Sodium Dodecyl Sulfate; D013656:Taurocholic Acid; D002787:Sterol Esterase