Abstract Thaumatin is a kind of natural sweet protein which has the characteristics of high sweetness, low calorie, safe and non-toxic, etc. And it has high commercial value in food processing, medicine and other fields. In this study, we employed a sequence that encode thaumatin II, along with goat beta-casein 5′ and 3′ regulatory elements, to construct a mammary gland-specific expression vector. Transgenic mice were generated using pronuclear microinjection, and the expression of thaumatin and its biological activities were assayed in the milk. PCR and southern blot analysis confirmed that the mice harbor thaumatin II transgenes. Thaumatin II retaining their sweetness was expressed in the mammary glands of transgenic mice, as determined by ELISA, western blot and sweetness intensity test. This research describes an initial step in the production of plant protein thaumatin-sweetened milk from large animals such as cow and goat.

中文翻译：

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功能性植物甜蛋白奇异果甜蛋白Ⅱ在转基因小鼠乳汁中的表达

摘要 索马甜是一种天然甜味蛋白质，具有高甜度、低热量、安全无毒等特点，在食品加工、医药等领域具有很高的商业价值。在这项研究中，我们采用了编码奇异果甜蛋白 II 的序列以及山羊 β-酪蛋白 5' 和 3' 调控元件，构建了一个乳腺特异性表达载体。使用原核显微注射产生转基因小鼠，并在牛奶中测定奇异果甜蛋白的表达及其生物活性。PCR 和Southern 印迹分析证实小鼠携带奇异果甜蛋白II 转基因。通过ELISA、蛋白质印迹和甜味强度测试确定，在转基因小鼠的乳腺中表达了保留其甜味的奇异果甜蛋白II。