Pseudomonas chlororaphis as a multiproduct platform: Conversion of glycerol into high-value biopolymers and phenazines

• Published in: New biotechnology Vol. 55; pp. 84 - 90
• Main Authors: de Meneses, Liane, Pereira, João Ricardo, Sevrin, Chantal, Grandfils, Christian, Paiva, Alexandre, Reis, Maria A.M., Freitas, Filomena
• Format: Journal Article Web Resource
• Language: English
• Published: Netherlands Elsevier B.V 25.03.2020; Elsevier Science Ltd
• Subjects: Bacteria; Biopolymers; Carbon sources; Cell culture; Cell proliferation; Chain length; Co-production; Coloration; Crystallinity; Degree of crystallinity; Engineering, computing & technology; Extracellular polysaccharide; Extracellular polysaccharides; Glucosamine; Glycerol; Ingénierie, informatique & technologie; Mannose; Materials science & engineering; Medium-chain-length polyhydroxyalkanoate; Melt temperature; Monomers; Phenazines; Poly-hydroxyalkanoate; Polyhydroxyalkanoates; Polymers; Polysaccharides; Pseudomonas; Pseudomonas chlororaphis; Rhamnose; Science des matériaux & ingénierie; Substrates; 2-OH-PHZ; PHA; EPS; mcl-PHA; CDM; PCA; Extracellular polysaccharide; PDI; Medium-chain-length polyhydroxyalkanoate; Pseudomonas chlororaphis; 2-OH-PCA; Co-production; Phenazines
• ISSN: 1871-6784; 1876-4347; 1876-4347
• DOI: 10.1016/j.nbt.2019.10.002

•Pseudomonas chlororaphis was cultivated using glycerol as the sole carbon source.•The strain synthesized phenazines concomitantly with cell growth.•mcl-PHA was accumulated in the biomass with a content of 19 wt%.•A high molecular weight exopolysaccharide (EPS) was secreted.•The conversion of glycerol into the three high-value products was demonstrated. Pseudomonas chlororaphis subsp. aurantiaca DSM 19603 was cultivated using glycerol as the sole carbon source for the simultaneous production of medium-chain length polyhydroxyalkanoates (mcl-PHA), extracellular polysaccharide (EPS) and phenazines. A maximum cell dry mass of 11.79 g/L was achieved with a mcl-PHA content of 19 wt%, corresponding to a polymer concentration of 2.23 g/L. A considerably higher EPS production, 6.10 g/L, was attained. Phenazines synthesis was evidenced by the bright orange coloration developed by the culture during the cell growth phase. The mcl-PHA produced by P. chlororaphis was composed mainly of 3-hydroxydecanoate (50 wt%) with lower amounts of 3-hydroxyoctanoate (17 wt%), 3-hydroxytetradecanoate (17 wt%), 3-hydroxydodecanoate (13 wt%) and 3-hydroxyhexanoate (3 wt%). This PHA showed unique thermal features being highly amorphous, with a degree of crystallinity of 27% and a low melting temperature (45.0 °C). The secreted EPS was mostly composed of glucose, glucosamine, rhamnose and mannose, with smaller amounts of three other unidentified monomers. Although the bioprocess can be improved further to define the optimal conditions to produce each bioproduct (mcl-PHA, EPS or phenazines), this study has demonstrated for the first time the ability of P. chlororaphis to simultaneously produce three high-value products from a single substrate.