Firsov Aleksey, Shaloiko Lyubov, Kozlov Oleg, Vinokurov Leonid, Vainstein Alexander, Dolgov Sergey
Branch of the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the RAS, Moscow Region, Pushchino, 142290, Russia.
Branch of the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry of the RAS, Moscow Region, Pushchino, 142290, Russia.
Protein Expr Purif. 2016 Jul;123:1-5. doi: 10.1016/j.pep.2016.03.002. Epub 2016 Mar 8.
Thaumatin, a supersweet protein from the African plant katemfe (Thaumatococcus daniellii Benth.), is a promising zero-calorie sweetener for use in the food and pharmaceutical industries. Due to limited natural sources of thaumatin, its production using transgenic plants is an advantageous alternative. We report a simple protocol for purification of recombinant thaumatin II from transgenic tomato. Thaumatin was extracted from ripe tomato fruit in a low-salt buffer and purified on an SP-Sephacryl column. Recombinant thaumatin yield averaged 50 mg/kg fresh fruit. MALDI-MS analysis showed correct processing of thaumatin in tomato plants. The recombinant thaumatin was indistinguishable from the native protein in a taste test. The purified tomato-derived thaumatin had an intrinsic sweetness with a threshold value in taste tests of around 50 nM. These results demonstrate the potential of an expression system based on transgenic tomato plants for production of recombinant thaumatin for the food and pharmaceutical industries.
索马甜是一种从非洲植物卡坦菲（Thaumatococcus daniellii Benth.）中提取的超甜蛋白，是一种有望用于食品和制药行业的零热量甜味剂。由于索马甜的天然来源有限，利用转基因植物生产索马甜是一种有利的替代方法。我们报告了一种从转基因番茄中纯化重组索马甜II的简单方案。索马甜在低盐缓冲液中从成熟番茄果实中提取，并在SP-葡聚糖凝胶柱上进行纯化。重组索马甜的产量平均为每千克新鲜果实50毫克。基质辅助激光解吸电离质谱分析表明索马甜在番茄植株中得到了正确加工。在味觉测试中，重组索马甜与天然蛋白没有区别。纯化后的源自番茄的索马甜具有内在甜味，味觉测试中的阈值约为50纳摩尔。这些结果证明了基于转基因番茄植株的表达系统在为食品和制药行业生产重组索马甜方面的潜力。
