Mao Shuhong, Liu Yanna, Yang Juanjuan, Ma Xiaoyu, Zeng Fang, Zhang Zhaohui, Wang Shan, Han Haichao, Qin Hui-Min, Lu Fuping
Key Laboratory of Industrial Fermentation Microbiology, Ministry of Education, Tianjin University of Science & Technology Tianjin 300457 China
State Key Laboratory of Food Nutrition and Safety, Tianjin University of Science & Technology Tianjin 300457 China
RSC Adv. 2019 Jul 31;9(41):23856-23863. doi: 10.1039/c9ra02520k. eCollection 2019 Jul 29.
Fructosyltransferases have been used in the industrial production of fructooligosaccharides (FOS). However, it is still not possible to explain the difference in FOS production based on the variations observed in the FOS synthesizing enzymes of . In the present study, a novel fructosyltransferase (FT-A) from TCCC41686 with high FOS synthesis ability was characterized. The FT-A gene was obtained and expressed in . A homology model of FT-A showed that the changes of residues identified outside the conserved domains were found to have an effect on its characteristics and its FOS-synthesis capacity. The optimal activity of the recombinant FT-A was observed at 50 °C and pH 6.0, and it was stable below 50 °C and over the range of pH 3.0-11.0. The and values of FT-A were 151.13 g L and 6.55 g L min, respectively. The production of FOS using the recombinant FT-A remained above 60% during 50-80 min of synthesis based on sucrose as substrate. The novel fructosyltransferase (FT-A) investigated in this study can potentially be applied for the efficient industrial production of FOS. The results also provide more valuable information for explaining the relationship between the structure and function of the FT-A.
果糖基转移酶已被用于低聚果糖(FOS)的工业生产。然而,基于在[具体来源]的FOS合成酶中观察到的变化,仍无法解释FOS生产中的差异。在本研究中,对来自TCCC41686的具有高FOS合成能力的新型果糖基转移酶(FT-A)进行了表征。获得了FT-A基因并在[具体宿主]中表达。FT-A的同源模型表明,在保守结构域之外鉴定出的残基变化对其特性及其FOS合成能力有影响。重组FT-A的最佳活性在50°C和pH 6.0下观察到,并且在50°C以下以及pH 3.0 - 11.0范围内稳定。FT-A的米氏常数(Km)和最大反应速度(Vmax)值分别为151.13 g/L和6.55 g/(L·min)。以蔗糖为底物,在合成50 - 80分钟期间,使用重组FT-A生产FOS的产量保持在60%以上。本研究中研究的新型果糖基转移酶(FT-A)有可能应用于FOS的高效工业生产。这些结果也为解释FT-A的结构与功能之间的关系提供了更有价值的信息。