3-D STRUCTURES OF TWO LOW-CALORIE PROTEIN SWEETENERS

索马汀是一种植物来源的蛋白质家族，味道甜美。 比糖强烈几千倍。Xoma已经净化了和 对两种主要的植物蛋白进行了测序，并努力改善口感 高质量，已经产生了100多种索马汀变种。其中大多数都是 已经通过酵母菌分泌系统产生了测试数量。 Cryschem正在通过以下方法解决植物索马汀的三维结构 X射线分析。具有改善口感的索马汀变体的结构 然后将确定属性，并特别强调 了解XOMA品味所显示区域的构象特征 影响甜味的测试。 人们对thaumatin的分子机制知之甚少 引起一种感官反应。我们有能力澄清这些 通过使用我们的许多受体结合重要的结构特征 基因工程甜蛋白。具有高度亲和力的Thaumatins 人类味觉测试和灵长类神经生理学测试中的味觉感受器 将用于从灵长类舌头组织提取液中分离受体。 将尝试确定互动的地点(S)。这个 将结构信息与受体结合研究相结合 定量的灵长类味觉测试应该能让我们设计出第二个 风味独特、稳定性好的蛋白质甜味剂的研制 特点。

The thaumatins are a family of plant-derived proteins with a sweet taste many thousand-fold more intense than sugar. XOMA has purified and sequenced the two major plant proteins and in an effort to improve taste quality, has generated more than 100 thaumatin variants. Most of these have been produced in test amounts via a yeast secretion system. Cryschem is solving the three-dimensional structure of plant thaumatin by X-ray analysis. The structures of thaumatin variants having improved taste properties will then be determined with special emphasis placed on understanding conformational features in regions shown by XOMA's taste tests to affect sweet taste. Little is known about the molecular mechanism by which thaumatin is able to elicit an organoleptic response. We are in a position to elucidate those structural features important for receptor binding by using a number of our genetically engineered sweet proteins. Thaumatins having high affinity for taste receptors in human taste tests and primate neurophysiological assays will be used to isolate receptors from primate tongue tissue extracts. Attempts will be made to identify the site(s) of interaction. The combination of structural information with receptor binding studies and quantitative primate taste tests should allow us to design a second generation of protein sweeteners with specific taste and stability characteristics.