Purification and characterization of the α-tocopherol transfer protein from rat liver

Abstract

α-Tocopheral transfer protein was purified from the 10 000 × g supernatant of rat liver. Two isoforms of the transfer protein exist, of which the isoelectric points are 5.0 and 5.1 as determined by chromatofocusing. These two isoforms have the same molecular weight; both showed molecular weight of approx. 30 500 on SDS-polyacrylamide gel electrophoresis. They cannot be distinguished from each other by amino acid composition or substrate specificity.