Wang Zhiyun, Xu Bo, Luo Huiying, Meng Kun, Wang Yuan, Liu Mengting, Bai Yingguo, Yao Bin, Tu Tao
Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China; College of Biological Sciences and Engineering, Jiangxi Agricultural University, Nanchang 330100, PR China.
College of Biological Sciences and Engineering, Jiangxi Agricultural University, Nanchang 330100, PR China.
J Biosci Bioeng. 2020 Jan;129(1):16-22. doi: 10.1016/j.jbiosc.2019.07.005. Epub 2019 Aug 8.
The economical production of pectin oligosaccharides with a specific degree of polymerization and structure from agro-food waste is an industrially important process. This study identified a novel pectate lyase gene (plhy1) from the thermophilic cellulolytic fungus H. insolens Y1 and tested its ability to produce pectin oligosaccharides. The recombinant PLHY1 produced in Pichia pastoris was superior to other similar enzymes due to its high thermal and pH stability. PLHY1 demonstrated optimal enzymatic activity at 55°C and pH 10.0 in the presence of 0.4 mM Ca, and preferred methyl esterified substrates for digestion. High performance anion exchange chromatography-pulsed amperometric detector and ultra high performance liquid chromatography in combination with electrospray ionization tandem mass spectrometry analysis showed that galacturonic acid-oligosaccharides with a small degree of polymerization (4-6) were the major hydrolysates produced by the degradation of apple peel pectin by PLHY1. The properties of PLHY1 make it valuable for application in the agro-food industry for the production of pectin oligosaccharides.
从农业食品废弃物中经济地生产具有特定聚合度和结构的果胶寡糖是一个具有重要工业意义的过程。本研究从嗜热纤维素分解真菌H. insolens Y1中鉴定出一个新的果胶酸裂解酶基因（plhy1），并测试了其生产果胶寡糖的能力。在毕赤酵母中产生的重组PLHY1由于其高热稳定性和pH稳定性，优于其他类似酶。PLHY1在0.4 mM Ca存在下，于55°C和pH 10.0时表现出最佳酶活性，并且优先选择甲酯化底物进行消化。高效阴离子交换色谱-脉冲安培检测器以及超高效液相色谱与电喷雾电离串联质谱分析表明，聚合度较小（4-6）的半乳糖醛酸寡糖是PLHY1降解苹果皮果胶产生的主要水解产物。PLHY1的特性使其在农业食品工业中生产果胶寡糖方面具有应用价值。
