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Showing 1 to 20 of 63 for “"PHB"”.
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Mechanistic investigation of polyhydroxybutyrate (PHB) synthases and elucidation of PHB biosynthesis and degradation process in Wautersia eutropha H16
Polyhydroxyalkanoate (PHA) synthase from various bacterial organisms is able to catalyze the polymerization of (R)-hydroxyalkanoate-CoAs into high molecular weight PHAs under nutrient- limited conditions in the presence of a carbon source. PHA synthases are representative of enzymes involved in …
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Studies on the mechanism of polyhydroxybutyrate (PHB) granule formation in Ralstonia eutropha H16/
Polyhydroxybutyrates (PHBs) are biodegradable polymers produced by bacteria in the form of insoluble granules for carbon storage. Insights into the mechanisms of granule formation are important for improving commercial PHB production and engineering new alternatives to petroleum-based plastics. …
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The role of the phasin PhaP in promoting polyhydroxybutyrate (PHB) granule formation in Caulobacter crescentus
Polyhydroxybutyrate (PHB) is a biodegradable polymer produced by many microorganisms when they find themselves limited in an essential nutrient such as nitrogen or phosphorus but in the presence of an abundant carbon source. PHB and other related polymers are of interest because they have valuable …
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Microbial Synthesis of Polymers: Alcaligenes Eutrophus and the Production of Poly - B - 3 - hydroxybutyric Acid (PHB)
PHB formation in bacteria is a means to store reserves of energy and carbon. The location and discovery of PHB has been known since 1926. In the last 30 years, much attention has been given to it, due to the polymer's characteristics. It is a thermoplastic polyester, the first truly biodegradable …
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Forward and inverse metabolic engineering strategies for improving polyhydroxybyrate production
… were applied to poly-3-hydroxybutyrate (PHB)production in Synechocystis PCC6803 [IME] and recombinant E. coli [FME] in this thesis.IME was appropriate for Synechocystis, where metabolic regulation of the native PHB pathway was not well understood. A high throughput screening method was …
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Solution properties and molecular size of polyhydroxybutyrate from recombinant Escherichia coli
… the regulation of the molecular weight of PHB during in vivo polymer production. Two recombinant strains of E. coli were used to produce material for this study: DH5a/pAeT41, containing the native operon from Alcaligenes eutrophus encoding the three enzymes necessary for the biosynthesis of …
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Control of product molecular weight in the enzymatic synthesis of a biodegradable polyester, polyhydroxybutyrate
Polyhydroxybutyrate (PHB) is a polymer accumulated by many bacterial species to store carbon and reducing equivalents. PHB is packaged intracellularly in inclusions termed "granules" that contain the polymer in an amorphous state, surrounded by a protein coat. The molecular weight (Mw) of PHB is …
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Molecular weight modulation in polyhydroxybutyrate fermentations
Polyhydroxybutyrate (PHB) is a material with significant potential for commercial applications. It has material properties similar to isotactic polypropylene; it can be produced from renewable resources; it is biodegradable. Unfortunately, it is very brittle when compared to polypropylene. The …
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Study of the miscibility, morphology, crystallization, and melting behavior of blends of poly(3-hydroxybutyrate) and poly(vinylidene fluoride)
… fluoride)/poly(3-hydroxybutyrate) (PVDF/PHB) blends prepared by melt and solution blending techniques. The blends exhibit - a single, composition dependent Tg. Dynamic crystallization studies indicate that PVDF crystallizes first in all blends containing more than 30% PVDF, and that the …
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Evolution of energy storage traits in symbiotic rhizobia
… into storage compounds like polyhydroxybutyrate (PHB). Although the conflict-of-interest between PHB accumulation and nitrogen-fixation has been discussed as a driving factor in the evolution of legume-rhizobia interactions, its role in natural populations is unclear. Therefore, this dissertation …
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Effects of solvents on thermotropic liquid crystalline copolyesters
… (PET) and para hydroxybenzoate (PHB), where PHB content varied from 0 mole percent up to 80 mole percent. The technique of chemical etching coupled with SEM and WAXS was utilized to obtain structural information. Morphological changes that occur when these materials are exposed to …
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Isolation and characterization of bacterial polyhydroxybutyrate inclusions
Polyhydroxybutyrate (PHB) is a carbon reserve found in some bacteria, and under nutrient limiting conditions accumulates intracellularly in the form of inclusion bodies. These inclusions contain proteins, and the PHB within the inclusions exists in an amorphous state. In this study a procedure to …
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The degradation of gel-spun poly(beta-hydroxybutyrate) fibrous matrix
Poly(β-hydroxybutyrate), (PHB), is a biologically produced, biodegradable thennoplastic with commercial potential. In this work the qualitative and quantitative investigations of the structure and degradation of a previously unstudied, novel, fibrous form of PHB, were completed. This gel-spun PHB …
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Dielectric relaxation behavior of poly(3-hydroxybutyrate)
The importance of Poly(3-hydroxybutyrate) (PHB) as a biodegradable material is well known. Due to ever increasing environmental awareness, significant efforts have been made to utilize PHB or its derivatives in producing disposable products. However, brittle mechanical properties of PHB hinder the …
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Transcriptional profiling and flux measurements of polyhydroxybutyrate production in Synechocystis
(cont.) to determine the CO₂ uptake rates and PHB production rates of strains engineered for enhanced CO₂ fixation and PHB production respectively.
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A study of the mechanical properties and the equilibrium nature of the blend of thermotropic liquid crystalline copolyesters
This work deals with the melt blend of 60/40 PHB/PET (p-hydroxybenzoic acid and polyethylene terephthalate) and 80/20 PHB/PET copolyesters in a 50:50 weight% ratio. Specifically, the interest was to determine as to how do the mechanical properties of the injection-molded parts from the blend …
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Phonologische Bewusstheit und Schriftspracherwerb
… Fähigkeiten zur phonologischen Bewusstheit (PhB) den Schwerpunkt. Der erfolgreiche Schriftspracherwerb ist nicht nur für den Bildungserfolg mit den damit verbundenen beruflichen und sozio‑ökonomischen Perspektiven wichtig, sondern auch für die aktive Teilhabe am sozialen und kulturellen Leben …
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An examination of biological phosphorus removal using bacterial counting and poly-β-hydroxybutyrate analysis in batch and continuous flow systems
… (1993). Substrate utilization was examined using PHB (Poly-β -Hydroxybutyrate - an internal substrate storage product) analysis by gas chromatography to supplement COD and acetate measurements. The results showed that Poly-P bacterial counts were significantly greater at a 5 day sludge age …
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Hyperlipoproteinemic persons: Relationship between locus of control, health value, protective health behaviors, and illness/injury experiences
… Value Survey; their protective health behaviors (PHB), using the Cardiovascular Protective Health Behavior Instrument; and their experiences with illness/injury (EII), obtained as part of the Demographic Instrument. Utilizing chi square statistical analysis, no significant relationship was found …
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