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Strain and process development for poly(3HB-co-3HP) fermentation by engineered Shimwellia blattae from glycerol.

Sato S, Andreeßen B, Steinbüchel A - AMB Express (2015)

Bottom Line: Poly(3-hydroxybytyrate-co-3-hydroxypropionate), poly(3HB-co-3HP), is a possible alternative to synthetic polymers such as polypropylene, polystyrene and polyethylene due to its low crystallinity and fragility.However, the cell density was rather low.In this study, we optimized the medium aiming at a more efficient PHA synthesis, and we engineered a S. blattae strain accumulating poly(3HB-co-3HP) with varying contents of the constituent 3-hydroxypropionate (3HP) depending on the cultivation conditions.

View Article: PubMed Central - PubMed

Affiliation: Institut für Molekular Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, Corrensstraße 3, D-48149 Münster, Germany.

ABSTRACT
Poly(3-hydroxybytyrate-co-3-hydroxypropionate), poly(3HB-co-3HP), is a possible alternative to synthetic polymers such as polypropylene, polystyrene and polyethylene due to its low crystallinity and fragility. We already reported that recombinant strains of Shimwellia blattae expressing 1,3-propanediol dehydrogenase DhaT as well as aldehyde dehydrogenase AldD of Pseudomonas putida KT2442, propionate-CoA transferase Pct of Clostridium propionicum X2 and PHA synthase PhaC1 of Ralstonia eutropha H16 are able to accumulate up to 14.5% (wtPHA/wtCDW) of poly(3-hydroxypropionate), poly(3HP), homopolymer from glycerol as a sole carbon source (Appl Microbiol Biotechnol 98:7409-7422, 2014a). However, the cell density was rather low. In this study, we optimized the medium aiming at a more efficient PHA synthesis, and we engineered a S. blattae strain accumulating poly(3HB-co-3HP) with varying contents of the constituent 3-hydroxypropionate (3HP) depending on the cultivation conditions. Consequently, 7.12, 0.77 and 0.32 gPHA/L of poly(3HB-co-3HP) containing 2.1, 8.3 and 18.1 mol% 3HP under anaerobic/aerobic (the first 24 hours under anaerobic condition, thereafter, aerobic condition), low aeration/agitation (the minimum stirring rate required in medium mixing and small amount of aeration) and anaerobic conditions (the minimum stirring rate required in medium mixing without aeration), respectively, were synthesized from glycerol by the genetically modified S. blattae ATCC33430 strains in optimized culture medium.

No MeSH data available.


Related in: MedlinePlus

Poly(3HB-co-3HP) accumulation ofShimwellia blattae Sb6BP. After 72 h of fermentation in BM under two-step condition. Hydrophobic inclusions were stained with Nile red and observed with a fluorescence microscope employing phase contrast (left), differential interference contrast (middle), and fluorescence microscopy at 312 nm (right), respectively.
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Fig2: Poly(3HB-co-3HP) accumulation ofShimwellia blattae Sb6BP. After 72 h of fermentation in BM under two-step condition. Hydrophobic inclusions were stained with Nile red and observed with a fluorescence microscope employing phase contrast (left), differential interference contrast (middle), and fluorescence microscopy at 312 nm (right), respectively.

Mentions: Analysis of polymer content and purity of the extracted polymer was done by gas chromatography (GC). For this dried cell mass or samples of isolated poly(3HB-co-3HP) and poly(3HB) were exposed to acidic methanolysis as described before (Brandl et al., 1998; Timm et al., 1990). For microscopic analysis of PHA-granules cells were stained with Nile red (Spiekermann et al., 1999) (Figure 2).Figure 2


Strain and process development for poly(3HB-co-3HP) fermentation by engineered Shimwellia blattae from glycerol.

Sato S, Andreeßen B, Steinbüchel A - AMB Express (2015)

Poly(3HB-co-3HP) accumulation ofShimwellia blattae Sb6BP. After 72 h of fermentation in BM under two-step condition. Hydrophobic inclusions were stained with Nile red and observed with a fluorescence microscope employing phase contrast (left), differential interference contrast (middle), and fluorescence microscopy at 312 nm (right), respectively.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4385116&req=5

Fig2: Poly(3HB-co-3HP) accumulation ofShimwellia blattae Sb6BP. After 72 h of fermentation in BM under two-step condition. Hydrophobic inclusions were stained with Nile red and observed with a fluorescence microscope employing phase contrast (left), differential interference contrast (middle), and fluorescence microscopy at 312 nm (right), respectively.
Mentions: Analysis of polymer content and purity of the extracted polymer was done by gas chromatography (GC). For this dried cell mass or samples of isolated poly(3HB-co-3HP) and poly(3HB) were exposed to acidic methanolysis as described before (Brandl et al., 1998; Timm et al., 1990). For microscopic analysis of PHA-granules cells were stained with Nile red (Spiekermann et al., 1999) (Figure 2).Figure 2

Bottom Line: Poly(3-hydroxybytyrate-co-3-hydroxypropionate), poly(3HB-co-3HP), is a possible alternative to synthetic polymers such as polypropylene, polystyrene and polyethylene due to its low crystallinity and fragility.However, the cell density was rather low.In this study, we optimized the medium aiming at a more efficient PHA synthesis, and we engineered a S. blattae strain accumulating poly(3HB-co-3HP) with varying contents of the constituent 3-hydroxypropionate (3HP) depending on the cultivation conditions.

View Article: PubMed Central - PubMed

Affiliation: Institut für Molekular Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, Corrensstraße 3, D-48149 Münster, Germany.

ABSTRACT
Poly(3-hydroxybytyrate-co-3-hydroxypropionate), poly(3HB-co-3HP), is a possible alternative to synthetic polymers such as polypropylene, polystyrene and polyethylene due to its low crystallinity and fragility. We already reported that recombinant strains of Shimwellia blattae expressing 1,3-propanediol dehydrogenase DhaT as well as aldehyde dehydrogenase AldD of Pseudomonas putida KT2442, propionate-CoA transferase Pct of Clostridium propionicum X2 and PHA synthase PhaC1 of Ralstonia eutropha H16 are able to accumulate up to 14.5% (wtPHA/wtCDW) of poly(3-hydroxypropionate), poly(3HP), homopolymer from glycerol as a sole carbon source (Appl Microbiol Biotechnol 98:7409-7422, 2014a). However, the cell density was rather low. In this study, we optimized the medium aiming at a more efficient PHA synthesis, and we engineered a S. blattae strain accumulating poly(3HB-co-3HP) with varying contents of the constituent 3-hydroxypropionate (3HP) depending on the cultivation conditions. Consequently, 7.12, 0.77 and 0.32 gPHA/L of poly(3HB-co-3HP) containing 2.1, 8.3 and 18.1 mol% 3HP under anaerobic/aerobic (the first 24 hours under anaerobic condition, thereafter, aerobic condition), low aeration/agitation (the minimum stirring rate required in medium mixing and small amount of aeration) and anaerobic conditions (the minimum stirring rate required in medium mixing without aeration), respectively, were synthesized from glycerol by the genetically modified S. blattae ATCC33430 strains in optimized culture medium.

No MeSH data available.


Related in: MedlinePlus