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Immobilization of Multi-biocatalysts in Alginate Beads for Cofactor Regeneration and Improved Reusability
Published on: April 22, 2016
Enhanced pullulanase production through expression system optimization and biofilm-immobilized fermentation
Peifang Ren1, Qiwei Dong1, Chaowei Zhou1
1National Engineering Research Center for Biotechnology, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, PR China; State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, PR China.
Abstract:
Pullulanase (PUL) plays a crucial role in breaking down α-1,6-glycosidic bonds in starch, a key process in starch processing and conversion. Based on PulB with high enzymatic activity, the expression of PUL in Bacillus subtilis was enhanced by plasmid screening, double promoter optimization, and signal peptide engineering. Furthermore, we innovatively employed a mussel foot protein to enhance the cell adhesion to carriers and utilized biofilm-based cell immobilization technology to optimize the fermentation process and stimulate biofilm formation. This approach led to a notably elevated enzyme activity, reaching 2233.56 U mL-1. The PUL crude enzyme solution, capable of generating high glucose syrup and resistant starch, paves the way for new avenues of exploration and advancement in research and industrial biotechnology.
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