title: Measurement of isoelectric points of phospholipid exchange proteins by gel isoelectric focusing.
abstract: A method of the estimation of isoelectric points of phospholipid exchange proteins is described. The phospholipid presumably bound to a phospholipid exchange protein was replaced with [3H]phosphatidylcholine of a high specific radioactivity by an incubation of the protein with liposomes containing the labeled lipid and dimannosyl diglyceride. After the incubation, a major portion of the liposomes was separated from the protein by an affinity of the liposomes to concanavalin A-Sepharose 2B. The isoelectric point of the protein was measured by gel isoelectric focusing of the protein, which was located by tritium radioactivity of the bound [3H]phosphatidylcholine. The method was used to measure isoelectric points of partially purified phospholipid exchange proteins in pig liver.
mesh_terms: D002352:Carrier Proteins / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007525:Isoelectric Focusing; D007526:Isoelectric Point; D008565:Membrane Proteins; D010713:Phosphatidylcholines / Q000378:metabolism; D049294:Phospholipid Transfer Proteins; D014316:Tritium
chemical_list: D002352:Carrier Proteins; D008565:Membrane Proteins; D010713:Phosphatidylcholines; D049294:Phospholipid Transfer Proteins; D014316:Tritium