Background: Management of gluten intolerance is currently possible only by consumption of a gluten-free diet (GFD) for a lifetime. The scientific community has been searching for alternatives to GFD, like the inclusion of natural proteases with meals or pre-treatment of gluten-containing foods with glutenases. Actinidin from kiwifruit has shown considerable promise in digesting immunogenic gliadin peptides compared to other plant-derived cysteine proteases. Methods: In this study, we aimed to understand the structural basis for the elevated protease action of actinidin against gliadin peptides by using an in silico approach. Results: Docking experiments revealed key differences between the binding of gliadin peptide to actinidin and papain, which may be responsible for their differential digestive action. Conclusion: Sequence comparison of different plant cysteine proteases highlights amino acid residues surrounding the active site pocket of actinidin that are unique to this molecule and hence likely to contribute to its digestive properties.

中文翻译：

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使用结构生物信息学了解猕猴桃素增强麸质酶活性的分子基础

背景：目前只能通过终生食用无麸质饮食（GFD）来治疗麸质不耐受。科学界一直在寻找 GFD 的替代品，例如在膳食中添加天然蛋白酶或用麸质酶对含麸质食品进行预处理。与其他植物来源的半胱氨酸蛋白酶相比，来自猕猴桃的猕猴桃素在消化免疫原性麦醇溶蛋白肽方面显示出相当大的前景。方法：在本研究中，我们旨在通过计算机方法了解猕猴桃素对麦醇溶蛋白肽的蛋白酶作用增强的结构基础。结果：对接实验揭示了麦醇溶蛋白肽与猕猴桃素和木瓜蛋白酶的结合之间的关键差异，这可能是其消化作用不同的原因。结论：不同植物半胱氨酸蛋白酶的序列比较突出了猕猴桃素活性位点袋周围的氨基酸残基，这些残基是该分子所独有的，因此可能有助于其消化特性。