Structure Determination of a New Type of Taste-modifying Protein with Activity of Modifying a Sour Taste into Sweet Taste.

一种具有将酸味改成甜味活性的新型味觉修饰蛋白的结构测定。

基本信息

批准号：
01480066
负责人：
KURIHARA Yoshie
金额：
$ 3.52万
依托单位：
Yokohama National University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1989
资助国家：
日本
起止时间：
1989 至 1991
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-01480066/
关键词：
curculin sweet protein taste-modifying protein 味覚修飾物質

项目摘要

A new taste-modifylng protein named curculin was extracted with 0.5 M NaCl solution from fruits of Curculiro atifolia and purified by ammonium sulfate fractionation, CM-Sepharose Ion-exchange chromatography, and gcl filtration. The purilied curculin thus obtained gave a single band having molecular welght of 12, 000 In sodium dodecyl sulfate-polyacrylamide gel electrophoresis In the presence of 8 M urea. The molecular weight determined by low-angle light scattcring was 27, 800. These results suggested that native curculin Is a dimer of 12, 000 dalton polypeptide. The complete amino acid sequence of curculin was determined by an automatic Edman degradation method. Curculin consists of 114 amino acid residues. Curculin itself elicits a sweet taste. After curculin, water elicits a sweet taste and sour substances induce stronger sweetness. No protein carrying both a sweet-tasting activity and taste-modifying activitics has ever been known. There were 5 sets of tripeptides common to miraculin (taste-modifying protein). 6 sets of tripeptides common to thaumatln (sweet protein) and 2 sets of tripeptides common to monellin (sweet protein). An enzymc immunoassay method for curculin was established. This method can accurately quantity 0.05-20 ng of curculin, sensitivity about 3000-times that of the psychometric method. Immunoblot analysis Indicated that antiserum to curculin was faintly reactive with miraculin, but not with thaumatin or moncllin. The mechanism of the taste-modifying actions of curculin were discussed.

用0.5 M NaCl溶液从姜黄酸盐的水果中提取一种新的味道抑制蛋白，并通过硫酸铵分馏，CM-隔离离子换层色谱和GCL过滤纯化。因此，获得的纯姜黄素在硫酸钠 - 硫酸钠 - 聚丙烯酰胺凝胶电泳中，在8 M尿素存在下，具有分子欢迎为12，000的单个带。通过低角度光划分确定的分子量为27、800。这些结果表明，天然姜黄素是12，000多肽多肽的二聚体。姜黄素的完整氨基酸序列是通过自动Edman降解方法确定的。姜黄素由114个氨基酸残基组成。姜黄素本身会引起甜味。姜黄素后，水会引起甜味和酸味的物质，可引起更强烈的甜味。尚无携带甜味活性和改善味觉激活的蛋白质。有5组与奇迹蛋白共同的三肽（调整蛋白质）。 thaumatln（甜蛋白）和2组三肽（甜蛋白）的三组三肽（甜蛋白）（甜蛋白）。建立了一种用于姜黄素的酶免疫测定法。该方法可以准确地量为0.05-20 ng的姜黄素，灵敏度约为3000倍的心理测量方法。免疫印迹分析表明，抗姜黄素的抗血清与奇迹蛋白有微弱反应，但不能与硫代蛋白或moncllin相应。讨论了姜黄素的味觉改良作用的机制。