3-D STRUCTURES OF TWO LOW-CALORIE PROTEIN SWEETENERS

Thaeurin是一个具有甜味的植物源蛋白质家族 比糖强烈几千倍 XOMA已经纯化并 对两种主要的植物蛋白质进行测序， 质量，已经产生了100多个索马甜变体。 大多数这些 已经通过酵母分泌系统以测试量产生。 Cryschem正在解决植物索马甜的三维结构， X射线分析。 具有改善的味道的索马甜变体的结构 然后将确定属性，特别强调 了解XOMA味道所显示区域的构象特征 影响甜味的测试。 人们对索马甜的分子机制知之甚少， 引发感官反应 我们可以解释这些 通过使用我们的一些研究， 转基因甜蛋白 具有高亲和性的Thalocyanins 人类味觉测试和灵长类动物神经生理学测定中的味觉受体 将用于从灵长类动物舌组织提取物中分离受体。 将尝试识别相互作用的部位。 的 结合结构信息与受体结合研究， 定量灵长类动物的味觉测试应该可以让我们设计第二个 产生具有特定味道和稳定性的蛋白质甜味剂 特色

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.