Application of inorganic phosphate limitation to efficient isoprene production in Pantoea ananatis.
J Appl Microbiol
; 128(3): 763-774, 2020 Mar.
Article
em En
| MEDLINE
| ID: mdl-31738465
ABSTRACT
AIMS:
Establishment of an efficient isoprene fermentation process by adopting inorganic phosphate limitation as the trigger to direct metabolic flux to the isoprene synthetic pathway. METHODS ANDRESULTS:
We constructed isoprene-producing strains of Pantoea ananatis (a member of the Enterobacteriaceae family) by integrating a heterologous mevalonate pathway and a metabolic switch that senses external inorganic phosphate (Pi) levels. This metabolic switch enabled dual-phase isoprene production, where the initial cell growth phase under Pi-saturating conditions was uncoupled from the subsequent isoprene production phase under Pi-limiting conditions. In fed-batch fermentation using our best strain (SWITCH-PphoC/pIspSM) in a 1-l bioreactor, isoprene concentration in the off-gas was maintained between 300 and 460 ppm during the production phase and at 20 ppm during the cell growth phase, respectively. The strain SWITCH-PphoC/pIspSM produced totally 2·5 g l-1 of isoprene from glucose with a 1·8% volumetric yield in 48 h.CONCLUSIONS:
This proof-of-concept study demonstrated that our Pi-dependent dual-phase production system using a P. ananatis strain as a producer has potential for industrial-scale isoprene fermentation. SIGNIFICANCE AND IMPACT OF THE STUDY This Pi-dependent dual-phase fermentation process could be an attractive and economically viable option for the production of various commercially valuable isoprenoids.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fosfatos
/
Pantoea
/
Hemiterpenos
Idioma:
En
Revista:
J Appl Microbiol
Assunto da revista:
MICROBIOLOGIA
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
Japão