Tadi Subbi Rami Reddy, Nehru Ganesh, Sivaprakasam Senthilkumar
BioPAT Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam, 781039, India.
Appl Biochem Biotechnol. 2022 Apr;194(4):1740-1754. doi: 10.1007/s12010-021-03783-7. Epub 2022 Jan 8.
3-Aminopropionic acid (3-APA) has wide applications in food, cosmetics, pharmaceuticals, chemical, and polymer industries. This present study aimed to develop an eco-friendly whole-cell biocatalytic process for the bio-production of 3-APA from fumaric acid (FA) using Bacillus megaterium. A dual-enzyme cascade route with aspartate-1-decarboxylases (ADC) from Bacillus subtilis and native aspartate ammonia-lyase (AspA) was developed. Divergent catalytic efficiencies between these two enzymes led to an imbalance between both enzyme reactions. In order to coordinate AspA and ADC expression levels, gene mining, optimization, and duplication strategies were employed. Additionally, culture cultivation conditions and biocatalysis process parameters were optimized. A maximum 3-APA titer was obtained (11.68 ± 0.26 g/L) with a yield of 0.78 g/g under the following optimal conditions: 45 °C, pH 6.0, and 15 g/L FA. This study established a biocatalysis process for the production of 3-APA from FA using the whole cells of the recombinant B. megaterium.
3-氨基丙酸（3-APA）在食品、化妆品、制药、化工和聚合物工业中有着广泛应用。本研究旨在开发一种利用巨大芽孢杆菌从富马酸（FA）生物生产3-APA的环保型全细胞生物催化工艺。构建了一条由枯草芽孢杆菌的天冬氨酸-1-脱羧酶（ADC）和天然天冬氨酸氨裂解酶（AspA）组成的双酶级联途径。这两种酶之间不同的催化效率导致了两个酶反应之间的不平衡。为了协调AspA和ADC的表达水平，采用了基因挖掘、优化和复制策略。此外，还对培养条件和生物催化工艺参数进行了优化。在45℃、pH 6.0和15 g/L FA的最佳条件下，获得了最高3-APA滴度（11.68±0.26 g/L），产率为0.78 g/g。本研究建立了利用重组巨大芽孢杆菌全细胞从FA生产3-APA的生物催化工艺。
