Mole Fraction Control of Poly([R]‐3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHB/HV) Synthesized by <i>Paracoccus denitrificans</i>

Mothes, Gisela; Ackermann, Jörg‐Uwe; Babel, Wolfgang

doi:10.1002/elsc.200320029

Cited by 13 publications

(12 citation statements)

References 19 publications

(19 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The bacterial origin of PHA makes this polyester a natural material and indeed, many microorganisms have evolved the ability to degrade these macromolecules (Madison and Huisman 1999). The diversity of different monomers that can be incorporated into PHA, combined with a biological polymerization system that generates high molecular weight materials, has resulted in an enormous range of new polymers that are potentially available and reason why has attracted commercial interest (Mothes et al 2004). PHA are regarded as thermoplastics, elastomers, and rubbers, they can be used in a wide variety of products including containers, bottles, razors, materials for food packaging, implants, suture filaments, and osteosynthetic material.…”

Section: Introductionmentioning

confidence: 99%

Characterization of polyhydroxyalkanoate and the phaC gene of Paracoccus seriniphilus E71 strain isolated from a polluted marine microbial mat

López‐Cortés¹,

Rodríguez‐Fernández²,

Latisnere-Barragán³

et al. 2009

World J Microbiol Biotechnol

View full text Add to dashboard Cite

Polyhydroxyalakanote (PHA) was produced by the marine bacteria Paracoccus seriniphilus Strain E71. Three methods were used for screening PHA in this strain:(1) microscopic analysis, (2) specifically designed primers for amplify fragments of phaC gene from Gram negative bacteria, and (3) measurements using spectroscopy, calorimetry, thermogravimetry, and rheology. The polyhydroxyalkanoic acid synthase gene (phaC) sequence had 77% identity with the phaC gene of P. denitrificans PD1222 strain. Additionally, the translated sequence showed an 86% similarity with the amino acid sequence of the phaC gene N-terminal portion of the P. denitrificans PD1222 strain. Our phaC sequence was closely related to two phaC sequences that correspond to P. denitrificans; therefore, this is the first report of a sequence of phaC that codifies a poly-(3-hydroxyalkanoate) synthase class I, specifically a polybeta-hydroxybutyrate polymerase from the marine bacteria Paracoccus seriniphilus. The polymer PHA of E71 melts at 167.86°C (T m ), which corresponded to the fusion of the crystalline polymer and thermally degrades at 296.52°C, indicating that the biopolymer has good thermal stability. Rheology showed that this polymer behaves as a nonNewtonian fluid. All these characteristics suggest that the E71 strain produces a PHA that corresponds to the crystalline thermoplastic polymer PHB type.

show abstract

Section: Introductionmentioning

confidence: 99%

Characterization of polyhydroxyalkanoate and the phaC gene of Paracoccus seriniphilus E71 strain isolated from a polluted marine microbial mat

López‐Cortés¹,

Rodríguez‐Fernández²,

Latisnere-Barragán³

et al. 2009

World J Microbiol Biotechnol

View full text Add to dashboard Cite

show abstract

“…The bacteria used were Paracoccus denitrificans and Cupriavidus necator JMP 134 (formerly Ralstonia eutropha), which can synthesize PHA to a content of about 70 % of cell dry mass from various carbon substrates [8][9][10]. The bacteria used were Paracoccus denitrificans and Cupriavidus necator JMP 134 (formerly Ralstonia eutropha), which can synthesize PHA to a content of about 70 % of cell dry mass from various carbon substrates [8][9][10].…”

Section: Introductionmentioning

confidence: 99%

Production of PHB from Crude Glycerol

Mothes

Schnorpfeil²,

Ackermann

2007

Engineering in Life Sciences

Self Cite

204

121

View full text Add to dashboard Cite

Crude glycerol – a by‐product of the large scale production of diesel oil from rape – is examined for its possible use as a cheap feedstock for the biotechnological synthesis of poly(3‐hydroxybutyrate) (PHB). The glycerol samples of various manufacturers differ in their contamination with salts (NaCl or K2SO4), methanol or fatty acids. At high cell density fermentation these pollutants could possibly accumulate to inhibiting concentrations. The bacteria used were Paracoccus denitrificans and Cupriavidus necator JMP 134, which accumulate PHB from pure glycerol to a content of 70 % of cell dry mass. When using crude glycerol containing 5.5 % NaCl, a reduced PHB content of 48 % was observed at a bacterial dry mass of 50 g/L. Furthermore the PHB yield coefficient was reduced, obviously due to osmoregulation. The effect of glycerol contaminated with K2SO4 was less pronounced. The molecular weight of PHB produced with P. denitrificans or C. necator from crude glycerol varies between 620000 and 750000 g/mol which allows the processing by common techniques of the polymer industry.

show abstract

“…But there are also some examples for the synthesis of PHA by chemostatic cultivation with high yield [17]. These conditions are also suitable to produce copolymers with a target mole fraction from two carbon substrates with different consumption rates [19,20] An additional spatial separation of the growth and production phases by a two-stage cultivation makes it possible to apply different conditions according to the different demands of the growth phase and the production phase. Conditions with high productivity could also be found if the residual concentration of the carbon substrate was almost zero (the so-called double limitation [18]).…”

Section: Eng Life Sci Full Papermentioning

confidence: 99%

Synthesis of Poly(3-hydroxybutyrate-co-4-hydrobutyrate) with a Target Mole Fraction of 4-Hydroxybutyric Acid Units by Two-Stage Continuous Cultivation ofDelftia acidovorans P4a

Mothes¹,

Ackermann

2005

Eng. Life Sci.

Self Cite

View full text Add to dashboard Cite

Delftia acidovorans P4a (DSMZ 10474) was grown in mineral medium on acetic acid at pH 8.0 without an additional supply of nutrients like yeast extract or polypeptone. Using acetic acid and γ‐butyrolactone (GBL), copolymers with a 4HB content from 2–90 mol % were detected in batch experiments, depending on the ratio of the both carbon substrates. Due to the different consumption rates of the individual carbon substrates a multitude of different target mole fractions were difficult to produce by fed‐batch fermentation. Therefore, the two‐stage continuous cultivation technique was applied with two fermenters connected in series. At stage 2, the optimum PHA productivity of the bioreactor and a target 4HB content of the polymer could be precisely adjusted by the composition of the two substrates. This cultivation strategy was especially convenient when toxic substrates like acetic acid and GBL were employed. Using mixtures of acetic acid and GBL (3.5–23.5 mol % GBL), copolymers with a target mole fraction of 2.7–19 % 4HB could be produced. The PHA content was in the range of 52–60 %. The dilution rates (D) of the first and second fermenter were 0.2 h–1 and 0.06 h–1, respectively.

show abstract

Mole Fraction Control of Poly([R]‐3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHB/HV) Synthesized by Paracoccus denitrificans

Cited by 13 publications

References 19 publications

Characterization of polyhydroxyalkanoate and the phaC gene of Paracoccus seriniphilus E71 strain isolated from a polluted marine microbial mat

Characterization of polyhydroxyalkanoate and the phaC gene of Paracoccus seriniphilus E71 strain isolated from a polluted marine microbial mat

Production of PHB from Crude Glycerol

Synthesis of Poly(3-hydroxybutyrate-co-4-hydrobutyrate) with a Target Mole Fraction of 4-Hydroxybutyric Acid Units by Two-Stage Continuous Cultivation ofDelftia acidovorans P4a

Contact Info

Product

Resources

About