Ma Tiange, Li Xingjiang, Montalbán-López Manuel, Wu Xuefeng, Zheng Zhi, Mu Dongdong
Anhui Fermented Food Engineering Research Center, School of Food and Biological Engineering, Hefei University of Technology, Hefei 230601, China.
Department of Microbiology, Faculty of Sciences, University of Granada, 18071 Granada, Spain.
Gels. 2022 Oct 20;8(10):674. doi: 10.3390/gels8100674.
(1) Background: Microbial transglutaminases (MTGase) catalyze protein crosslink. This is useful in the food industry to improve gelation, water holding capacity, and emulsifying capacity during foodstuff manufacturing. The production of MTGase in wild-type strains renders low yield and high costs of downstream purification, limiting its industrial applications. (2) Methods: In this work, MTGase from BH072 (BaMTGase) has been heterologously expressed in , using the signal peptide Usp45 to direct the secretion of recombinant BaMTGase out of the cell for easier purification. (3) Results: In these conditions, MTGase was purified with a high yield (48.7 ± 0.2 mg/L) and high enzyme activity (28.6 ± 0.5 U/mg). Next, BaMTGase was tested for industrial applications. Recombinant BaMTGase and commercial MTGase were used for SPI solution crosslinking. BaMTGase formed a harder gel with higher water-holding capacity and a dense and smooth gel microstructure. (4) Conclusions: This work provides an attractive food-grade cell factory for the food industry and offers a suitable chassis for MTGase production.
(1) 背景：微生物转谷氨酰胺酶（MTGase）催化蛋白质交联。这在食品工业中有助于在食品制造过程中改善凝胶化、持水能力和乳化能力。野生型菌株中MTGase的产量较低，下游纯化成本较高，限制了其工业应用。(2) 方法：在本研究中，来自BH072的MTGase（BaMTGase）已在[具体表达宿主]中进行异源表达，使用信号肽Usp45引导重组BaMTGase分泌到细胞外，以便于纯化。(3) 结果：在此条件下，MTGase以高产率（48.7±0.2mg/L）和高酶活性（28.6±0.5U/mg）被纯化。接下来，对BaMTGase进行工业应用测试。重组BaMTGase和商业MTGase用于大豆分离蛋白（SPI）溶液交联。BaMTGase形成了具有更高持水能力的更硬凝胶以及致密且光滑的凝胶微观结构。(4) 结论：这项工作为食品工业提供了一个有吸引力的食品级细胞工厂，并为MTGase生产提供了一个合适的底盘。
