文献类型：期刊文献

英文题名：Catalytic and Structural Characterization of a Browning-Related Protein in Oriental Sweet Melon (Cucumis Melo var. Makuwa Makino)

作者：Liu, Siyu[2];Murtaza, Ayesha[1,3];Liu, Yan[4];Hu, Wanfeng[1,3];Xu, Xiaoyun[1,3];Pan, Siyi[1,3]

机构：[1]Huazhong Agr Univ, Coll Food Sci & Technol, Wuhan, Hubei, Peoples R China;[2]Peking Univ, Shenzhen Grad Sch, State Key Lab Chem Oncogen, Key Lab Chem Genom, Shenzhen, Peoples R China;[3]Huazhong Agr Univ, Minist Educ, Key Lab Environm Correlat Dietol, Wuhan, Hubei, Peoples R China;[4]East China Univ Sci & Technol, State Key Lab Bloreactor Engn, Shanghai, Peoples R China

年份：2018

卷号：6

外文期刊名：FRONTIERS IN CHEMISTRY

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000442508300001)】；

基金：This study was supported by the Hubei Province Technical Innovation Special Major Project (CXZD2017000255), Fundamental Research Funds for the Central Universities (2662018JC018) and National Natural Science Foundation of China (No. 31401507).

语种：英文

外文关键词：browning-related protein (BRP); polyphenol oxidase (PPO); purification; melon; structural characterization

摘要：Polyphenol oxidase (PPO) in plants plays an important role in browning reactions andmay affect the quality of sweet melon products. In this study, a browning-related protein (BRP) with PPO activity was partially purified from oriental sweet melon (Cucumis melo var. makuwa Makino) by salt precipitation and column chromatography. The BRP possessed a high degree of identity with several chitinase proteins, particularly defense-related proteins, by MS identification. Pyrogallol was determined as the most appropriate substrate for BRP (K-m = 0.04278M). BRP exhibited extreme resistance under alkaline and high temperature conditions when pyrogallol was used as substrate. Polyacrylamide gel electrophoresis (PAGE) analysis indicated that BRP was a homo-dimer of two subunits and had a molecular weight of 37 kDa. Structural analysis indicated that the alpha-helix was the dominant conformation of BRP. The active site of the protein might be buried deeply in the protein, and BRP might be monodispersed in an aqueous system.