期刊名称：Journal of Nutritional Science and Vitaminology
印刷版ISSN：0301-4800
电子版ISSN：1881-7742
出版年度：1984
卷号：30
期号：1
页码：1-10
DOI：10.3177/jnsv.30.1
出版社：Center for Academic Publications Japan
摘要：A thiamine-binding protein was purified from the extract of rice bran acetone powder by conventional procedures of acid precipitation, a series of column chromatography on DEAE-Sephadex A-50 and DEAE-cellulose, and gel filtration of Sephadex G-200. The purified thiamine-binding protein was nearly homogeneous as judged by disc gel electrophoresis and the molecular weight was estimated to be 94, 000 by gel filtration on Sephadex G-200 and 50, 000 by sodium dodecylsulfate (SDS) gel electrophoresis, suggesting that the protein is composed of two identical subunits. The apparent K d and B max of the binding for [14C]thiamine was 0.44±0.05 μM and 17.2±0.7 nmol/mg of protein, respectively. The optimal pH for the binding is between 8.0 and 9.0. From the competition experiment using several thiamine derivatives, high binding specificity of the protein for thiamine was presumed.
