Slootstra J W, De Geus P, Haas H, Verrips C T, Meloen R H
Department of Biomolecular Recognition, Institute for Animal Science and Health, Lelystad, The Netherlands.
Chem Senses. 1995 Oct;20(5):535-43. doi: 10.1093/chemse/20.5.535.
Epitopes on thaumatin and monellin were studied using the PEPSCAN-technology. The antibodies used were raised against thaumatin. Only antibodies that, in an ELISA, both recognized thaumatin and monellin were used in the PEPSCAN-analyses. On thaumatin two major overlapping epitopes were identified. On monellin no epitopes could be identified. The identified epitope region on thaumatin shares structural features with various peptide and protein sweeteners. It contains an aspartame-like site which is formed by Asp21 and Phe80, tips of the two extruding loops KGDAALDAGGR19-29 and CKRFGRPP77-84, which are spatially positioned next to each other. Furthermore, sub-sequences of the KGDAALDAGGR19-29 loop are similar to peptide-sweeteners such as L-Asp-D-Ala-L-Ala-methyl ester and L-Asp-D-Ala-Gly-methyl ester. Since the aspartame-like Asp21-Phe80 site and the peptide-sweetener-like sequences are also not present in non-sweet thaumatin-like proteins it is postulated that the KGDAALDAGGR19-29- and CKRFGRPP77-84 loop contain important sweet-taste determinants. This region has previously not been implicated as a sweet-taste determinant of thaumatin.
利用PEPSCAN技术研究了奇异果甜蛋白和莫奈林的表位。所使用的抗体是针对奇异果甜蛋白产生的。在PEPSCAN分析中，仅使用了在酶联免疫吸附测定（ELISA）中既能识别奇异果甜蛋白又能识别莫奈林的抗体。在奇异果甜蛋白上鉴定出两个主要的重叠表位。在莫奈林上未鉴定出表位。在奇异果甜蛋白上鉴定出的表位区域与各种肽和蛋白质甜味剂具有结构特征。它包含一个由Asp21和Phe80形成的类似阿斯巴甜的位点，这是两个突出环KGDAALDAGGR19 - 29和CKRFGRPP77 - 84的末端，它们在空间上彼此相邻。此外，KGDAALDAGGR19 - 29环的子序列与肽甜味剂如L - Asp - D - Ala - L - Ala - 甲酯和L - Asp - D - Ala - Gly - 甲酯相似。由于类似阿斯巴甜的Asp21 - Phe80位点和类似肽甜味剂的序列在非甜味的类奇异果甜蛋白中也不存在，因此推测KGDAALDAGGR19 - 29和CKRFGRPP77 - 84环包含重要的甜味决定因素。该区域以前未被认为是奇异果甜蛋白的甜味决定因素。
