School of Bioscience and Bioengineering, South China University of Technology, Guangzhou Higher Education Mega Center, Panyu District, Guangzhou, Guangdong, 510006, PR China.
Department of Food and Bioengineering, Guangdong Industry Technical College, Guangzhou, 510300, China.
Enzyme Microb Technol. 2018 May;112:35-42. doi: 10.1016/j.enzmictec.2018.02.002. Epub 2018 Feb 5.
The use of cell wall degrading enzymes of Trichoderma is a promising alternative for improving food storage. The aspartic protease P6281 secreted by the fungus Trichoderma harzianum plays an important role in mycoparasitism on phytopathogenic fungi. In this study, recombinant P6281 (rP6281) expressed in Pichia pastoris showed high activity of 321.8 U/mL. Maximum activity was observed at pH 2.5 and 40 °C, and the enzyme was stable in the pH range of 2.5-6.0. rP6281 significantly inhibited spore germination and growth of plant and animal pathogenic fungi such as Botrytis cinerea, Mucor circinelloides, Aspergillus fumigatus, Aspergillus flavus, Rhizoctonia solani, and Candida albicans. Transmission electron microscopy revealed that rP6281 efficiently damages the cell wall of Botrytis cinerea. In addition, the protease significantly inhibited the development of grey mold that causes rotting of apple, orange, and cucumber, indicating that rP6281 may be developed as an effective anti-mold agent for fruit storage.
木霉细胞壁降解酶的使用是改善食品储存的一种很有前途的替代方法。哈茨木霉分泌的天冬氨酸蛋白酶 P6281 在对植物病原菌真菌的真菌寄生中起着重要作用。在这项研究中，在巴斯德毕赤酵母中表达的重组 P6281（rP6281）表现出 321.8 U/mL 的高活性。在 pH 2.5 和 40°C 时观察到最大活性，并且该酶在 pH 2.5-6.0 范围内稳定。rP6281 显著抑制了植物和动物病原菌真菌如灰葡萄孢、卷枝毛霉、烟曲霉、黄曲霉、立枯丝核菌和白色念珠菌的孢子萌发和生长。透射电子显微镜显示 rP6281 有效地破坏了灰葡萄孢的细胞壁。此外，该蛋白酶显著抑制了导致苹果、橙子和黄瓜腐烂的灰霉病的发展，表明 rP6281 可能被开发为一种有效的水果贮藏防霉剂。
