High yield recombinant thermostable α-amylase production using an improved Bacillus licheniformis system
Date
2009-10
Authors
Niu, Dandan
Zuo, Zhirui
Shi, Gui-Yang
Wang, Zheng-Xiang
Journal Title
Journal ISSN
Volume Title
Publisher
BioMed Central
Abstract
Abstract
Background
Some strains of Bacillus licheniformis have been improved by target-directed screening as well as by classical genetic manipulation and used in commercial thermostable α-amylase and alkaline protease production for over 40 years. Further improvements in production of these enzymes are desirable.
Results
A new strain of B. licheniformis CBBD302 carrying a recombinant plasmid pHY-amyL for Bacillus licheniformis α-amylase (BLA) production was constructed. The combination of target-directed screening and genetic recombination led to an approximately 26-fold improvement of BLA production and export in B. licheniformis. Furthermore, a low-cost fermentation medium containing soybean meal and cottonseed meal for BLA production in shake-flasks and in a 15 liter bioreactor was developed and a BLA concentration of up to 17.6 mg per ml growth medium was attained.
Conclusion
This production level of BLA by B. licheniformis CBBD302(pHY-amyL) is amongst the highest levels in Gram-positive bacteria reported so far.
Description
The original publication is available at http://www.microbialcellfactories.com/content/8/1/58
Keywords
Biotechnology, Bacillus licheniformis -- Genetic manipulation, Microbiology
Citation
Niu, D., Zuo, Z., Shi, G-Y. & Wang, Z-X. 2009. High yield recombinant thermostable α-amylase production using an improved Bacillus licheniformis system. Microbial Cell Factories, 8(1):58, doi.org/10.1186/1475-2859-8-58.