山药蛋白及其致痒成分分析

Analysis of Chinese yam proteins and the itch-causing components

目的探讨山药蛋白及其引起人体皮肤瘙痒的活性成分。方法将山药蛋白分离纯化,得到不同的蛋白组分,并对各组分进行瘙痒评价。对山药蛋白及分离后各组分蛋白进行质谱分析和蛋白质定性组学分析。结果山药蛋白经分离纯化,获得4个组分,其中组分1具有致痒性。对山药蛋白进行质谱分析,鉴定到1529个蛋白质,蛋白注释显示半胱氨酸蛋白酶2(CCP2)、B样组织蛋白酶2(CATHB2)和Oryzainα链(Os04g0650000)属于木瓜蛋白酶家族半胱氨酸蛋白酶。基因本体论(GO)富集分析结果显示,山药蛋白参与谷胱甘肽转移酶激活、铜离子结合和氧化还原酶激活等过程。蛋白结构域富集到磷酸葡萄糖异构酶、Ⅲ类转氨酶和木瓜蛋白酶家族半胱氨酸蛋白酶等。致痒组分质谱分析鉴定到235个蛋白质。通过构建蛋白-蛋白互作网络,发现CCP2是连接2个独立网络的核心分子。在Pfam数据库中,CCP2注释到“木瓜蛋白酶家族半胱氨酸蛋白酶”。结论山药蛋白中包含CCP2的组分可引起人体皮肤瘙痒。CCP2可能是山药中引起人体皮肤瘙痒的活性成分。

Objective To analyze yam proteins and the active components,which cause itching on human skin.Methods Through separation and purification of yam proteins,the pruritus evaluation of each component was carried out to identify the active components,which cause skin itching.Mass spectrometry and proteomics analyses were carried out on yam proteins and each protein component obtained after separation.Results Out of the four components,obtained after separation and purification procedures,component 1 was found to be itchy.A total of 1529 yam proteins were identified using mass spectrometry analysis.The protein annotation showed that CCP2,CATHB2,and Os04g0650000 belonged to the papain family cysteine protease.GO enrichment analysis was significantly involved in glutathione transferase activation,copper ion binding,and oxidoreductase activation.The protein domain was enriched in phosphoglucose isomerase,classⅢtransaminase,and papain family cysteine proteases.Mass spectrometry analysis of the itchy ingredient identified 235 proteins.A protein-protein interaction network was constructed,and it revealed CCP2 as the core molecule connecting two independent networks.In the Pfam database,CCP2 was annotated to“papain family cysteine protease.”Conclusion The component containing CCP2 in yam proteins could cause itching on human skin.CCP2 might be the active ingredient in yam responsible for human skin pruritus.