Abstract
Background: A representative hydrogen-oxidizing bacterium Cupriavidus necator H16 has attracted much attention as hosts to recycle carbon dioxide (CO2) into a biodegradable polymer, poly(R)-3-hydroxybutyrate (PHB). Although C. necator H16 has been used as a model PHB producer, the PHB production rate from CO2 is still too low for commercialization. Results: Here, we engineer the carbon fixation metabolism to improve CO2 utilization and increase PHB production. We explore the possibilities to enhance the lithoautotrophic cell growth and PHB production by introducing additional copies of transcriptional regulators involved in Calvin Benson Bassham (CBB) cycle. Both cbbR and regA-overexpressing strains showed the positive phenotypes for 11% increased biomass accumulation and 28% increased PHB production. The transcriptional changes of key genes involved in CO2—fixing metabolism and PHB production were investigated. Conclusions: The global transcriptional regulator RegA plays an important role in the regulation of carbon fixation and shows the possibility to improve autotrophic cell growth and PHB accumulation by increasing its expression level. This work represents another step forward in better understanding and improving the lithoautotrophic PHB production by C. necator H16.
Original language | English |
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Article number | 231 |
Journal | Microbial Cell Factories |
Volume | 21 |
Issue number | 1 |
DOIs | |
Publication status | Published - 2022 Dec |
Bibliographical note
Funding Information:This research was supported by the National Research Foundation of Korea (NRF) Grant funded by the Korean government (MSIT) (No. RS-2022-00156236). The authors also appreciate the additional support provided by the Korea Institute of Science and Technology (KIST) Institutional Programs (2E31853 and 2E31833).
Publisher Copyright:
© 2022, The Author(s).
Keywords
- Calvin Benson Bassham (CBB) cycle
- Carbon dioxide fixation
- Cupriavidus necator H16
- Lithoautotrophic culture
- Polyhydroxybutyrate (PHB)
- Transcriptional regulator
ASJC Scopus subject areas
- Biotechnology
- Bioengineering
- Applied Microbiology and Biotechnology