Capuano Edoardo, Fedele Francalisa, Mennella Carmela, Visciano Marianna, Napolitano Aurora, Lanzuise Stefania, Ruocco Michelina, Lorito Matteo, del Castillo María Dolores, Fogliano Vincenzo
Dipartimento di Scienza degli Alimenti and Dipartimento Ar.Bo.Pa.Ve. sez. Patologia Vegetale, University of Napoli Federico II, via Università 100, 80055 Portici, Italy.
J Agric Food Chem. 2007 May 16;55(10):4189-95. doi: 10.1021/jf0700024. Epub 2007 Apr 17.
Amadoriase I is a fructosyl amine oxidase from Aspergillus fumigatus that catalyzes the oxidation of Amadori products (APs) producing glucosone, H2O2, and the corresponding free amine. All the enzymes of this family discovered so far only deglycate small molecular weight products and are inactive toward large molecular weight substrates, such as glycated BSA or ribonuclease A. Therefore, they cannot be used to reverse protein glycation occurring in diabetes or in foods. In this paper, the effect of Amadoriase I added during the in vitro reaction between glucose and peptides having different polarities or proteins with molecular weights ranging from to 5 to 66 kDa was tested. The formation of APs was monitored by ESI-MS of intact glycated protein or peptides and by measuring the Nepsilon-(1-deoxy-d-fructos-1-yl)-L-lysine and furosine concentrations. Results showed that the formation of APs is reduced up to 80% when peptides and glucose are incubated in the presence of Amadoriase. The effect is more evident for hydrophobic peptides. In protein-glucose systems, the effect was dependent on the molecular weight and steric hindrance being negligible for BSA and at a maximum for insulin, where the formation of APs was reduced up to 60%. These findings indicate new potential applications of Amadoriase I as an efficient tool for inhibiting protein glycation in real food systems.
阿玛多里酶I是一种来自烟曲霉的果糖基胺氧化酶，它催化阿玛多里产物（APs）的氧化，生成葡萄糖酮、过氧化氢和相应的游离胺。到目前为止发现的该家族所有酶仅能使小分子产物脱糖基化，对大分子底物如糖化牛血清白蛋白或核糖核酸酶A无活性。因此，它们不能用于逆转糖尿病或食品中发生的蛋白质糖基化。本文测试了在葡萄糖与不同极性的肽或分子量在5至66 kDa之间的蛋白质的体外反应过程中添加阿玛多里酶I的效果。通过完整糖化蛋白质或肽的电喷雾质谱以及测量Nε-（1-脱氧-D-果糖-1-基）-L-赖氨酸和糠氨酸浓度来监测APs的形成。结果表明，当肽和葡萄糖在阿玛多里酶存在下孵育时，APs的形成减少高达80%。对于疏水性肽，这种效果更明显。在蛋白质-葡萄糖体系中，这种效果取决于分子量，空间位阻对牛血清白蛋白可忽略不计，对胰岛素则最大，其中APs的形成减少高达60%。这些发现表明阿玛多里酶I作为一种在实际食品体系中抑制蛋白质糖基化的有效工具具有新的潜在应用。
