High cell density cultivation of Pseudomonas putida KT2440 using glucose without the need for oxygen enriched air supply

Abstract

High Cell Density (HCD) cultivation of bacteria is essential for the majority of industrial processes to achieve high volumetric productivity (g L(-1) h(-1) ) of a bioproduct of interest. This study developed a fed batch bioprocess using glucose as sole carbon and energy source for the HCD of the well described biocatalyst Pseudomonas putida KT2440 without the supply of oxygen enriched air. Growth kinetics data from batch fermentations were used for building a bioprocess model and designing feeding strategies. An exponential followed by linearly increasing feeding strategy of glucose was found to be effective in maintaining biomass productivity while also delaying the onset of dissolved oxygen (supplied via compressed air) limitation. A final cell dry weight (CDW) of 102 g L(-1) was achieved in 33 h with a biomass productivity of 3.1 g L(-1) h(-1) which are the highest ever reported values for P. putida strains using glucose without the supply of pure oxygen or oxygen enriched air. The usefulness of the biomass as a biocatalyst was demonstrated through the production of the biodegradable polymer polyhydroxyalkanoate (PHA). When nonanoic acid (NA) was supplied to the glucose grown cells of P. putida KT2440, it accumulated 32% of CDW as PHA in 11 h (2.85 g L(-1) h(-1) ) resulting in a total of 0.56 kg of PHA in 18 L with a yield of 0.56 g PHA g NA(-1) .

Recent strategies for efficient production of polyhydroxyalkanoates by micro-organisms

“…Anoxic environment might also be economically viable for the PHA accumulation, as it accumulates higher PHA production (Davis et al . ). Besides, fermentation strategy can also influence the production of PHAs.…”

“…Chen et al optimized the upstream process of PHA production by mixing microbial cultures and feeding substrates as well as pH control during the fermentations process . Anoxic environment might also be economically viable for the PHA accumulation, as it accumulates higher PHA production (Davis et al 2015). Besides, fermentation strategy can also influence the production of PHAs.…”

“…PLoS ONE 9, e98873. Cerrone, F., Davis, R., Kenny, S.T., Woods, T., O'Donovan, A., Gupta, V.K., Tuohy, M., Babu, R.P. et al (2015) Use of a mannitol rich ensiled grass press juice (EGPJ) as a sole carbon source for polyhydroxyalkanoates (PHAs) production through high cell density cultivation.…”

Thermal properties of 3‐hydroxy fatty acids and their binary mixtures as phase change energy storage materials

“…23,24 Two different types of polyhydroxyalkanoates (PHA) were provided by Bioplastech Ltd (Dublin, Ireland). 23,24 Two different types of polyhydroxyalkanoates (PHA) were provided by Bioplastech Ltd (Dublin, Ireland).…”

Properties of alternative microbial hosts used in synthetic biology: towards the design of a modular chassis

“…P. putida KT2440 can also naturally accumulate polyhydroxyalkanoates (PHAs) to high yields [58], even under industrial-scale production conditions [59], making this strain an ideal candidate for commercial synthesis of biopolymers with thermoplastic properties. This natural mechanism can be tuned to produce plastics with very specific properties, for instance changing the length of the side chain length of the polymers [60].…”