Enhanced production of 2,3-butanediol by engineered Bacillus subtilis |
| |
Authors: | Ranjita Biswas Masaru Yamaoka Hideki Nakayama Takashi Kondo Ken-ichi Yoshida Virendra S. Bisaria Akihiko Kondo |
| |
Affiliation: | (1) Organization of Advance Science and Technology, Kobe University, Kobe 657-8501, Japan;(2) Department of Agrobioscience, Graduate School of Agricultural Science, Kobe University, Kobe 657-8501, Japan;(3) Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, New Delhi, 110016, India;(4) Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan; |
| |
Abstract: | Production of 2,3-butanediol by Bacillus subtilis takes place in late-log or stationary phase, depending on the expression of bdhA gene encoding acetoin reductase, which converts acetoin to 2,3-butanediol. The present work focuses on the development of a strain of B. subtilis for enhanced production of 2,3-butanediol in early log phase of growth cycle. For this, the bdhA gene was expressed under the control of P alsSD promoter of AlsSD operon for acetoin fermentation which served the substrate for 2,3-butanediol production. Addition of acetic acid in the medium induced the production of 2,3-butanediol by 2-fold. Two-step aerobic–anaerobic fermentation further enhanced 2,3-butanediol production by 4-fold in comparison to the control parental strain. Thus, addition of acetic acid and low dissolved oxygen in the medium are involved in activation of bdhA gene expression from P alsSD promoter in early log phase. Under the conditions tested in this work, the maximum production of 2,3-butanediol, 2.1 g/l from 10 g/l glucose, was obtained at 24 h. Furthermore, under the optimized microaerophilic condition, the production of 2,3-butanediol improved up to 6.1 g/l and overall productivity increased by 6.7-fold to 0.4 g/l h in the engineered strain compared to that in the parental control. |
| |
Keywords: | |
本文献已被 PubMed SpringerLink 等数据库收录! |
|