Genetically engineered deletion in the N-terminal region of nifA1 in R. capsulatus to enhance hydrogen production |
| |
| Affiliation: | 1. State Key Laboratory of Multiphase Flow in Power Engineering, Xi''an Jiaotong University, Xi''an 710049, Shaanxi, China;2. College of Biology and Oceanography, Weifang University, Weifang 261061, Shandong, China;3. College of Bioresources Chemical & Materials Engineering, Shaanxi University of Science & Technology, Xi''an 710021, Shaanxi, China;1. U.S. Department of Energy, National Energy Technology Laboratory, 3610 Collins Ferry Road, P.O. Box 880, Morgantown, WV, 26507-0880;2. NETL Support Contractor, 3610 Collins Ferry Road Morgantown, WV, 25607, USA;1. Electrochemistry Research Laboratory, Department of Physical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz, Iran;2. Hydrogen Energy and Sonochemistry Research Group, Department of Energy and Process Engineering, Faculty of Engineering, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway;3. Department of Energy and Process Engineering & ENERSENSE, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway;1. Department of Electrical Automation, Hebei University of Water Resources and Electric Engineering, Cangzhou, 061001, China;2. Computer Department, Hebei University of Water Resources and Electric Engineering, Cangzhou, 061001, China;3. Enrolment and Vocation Guidance Office, Hebei University of Water Resources and Electric Engineering, Cangzhou, 061001, China;4. Electrical Engineering Department, Sun-Life Company, Baku, Azerbaijan;1. Fronius International GmbH, Guenter-Fronius-Straße 1, 4600 Thalheim, Austria;2. K1-MET GmbH, Stahlstraße 14, 4020 Linz, Austria |
| |
| Abstract: | NifA is the primary activator of nitrogenase, and the N-terminal domain of nifA is sensitive to ammonium concentration. In this work, a mutant Rhodobacter capsulatus ZX01 with a genetically engineered deletion in the N-terminal region of nifA1 was constructed by employing overlap extension PCR to mitigate the inhibition of ammonium on nitrogenase expression in photosynthetic bacteria. The effects of different ammonium ion concentrations on the growth and photo-fermentative hydrogen production performance of wild-type strain R. capsulatus SB1003 and mutant ZX01 with glucose and volatile fatty acids as the carbon sources were studied, respectively. When the ratio of NH4+-N was 20% and 30%, the hydrogen yield of the mutant ZX01 was enhanced by 14.8% and 20.9% compared with that of R. capsulatus SB1003 using 25 mM acetic acid and 34 mM butyric acid as the carbon source, respectively. In comparison, using 30 mM glucose as the carbon source, the hydrogen yield of ZX01 was increased by 17.7% and 22.2% compared with that of R. capsulatus SB1003 when the ratio of NH4+-N was 20% and 30%, and the nitrogenase activity of ZX01 was also enhanced by 38.0% and 47.6%, respectively. When using 10 mM NH4+ as a single nitrogen source, ZX01 showed a 2.6-fold increase in H2 production. These results indicated that ZX01 demonstrated higher ammonium tolerance and better hydrogen production performance than the wild-type. The deletion in the N-terminal region of nifA1 could partially de-repress the nitrogenase activity inhibited by ammonium. |
| |
| Keywords: | Hydrogen production Ammonium tolerance N-terminal Gene splicing |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
