Pseudomonas putida KT2440 is able to synthesize large amounts of medium-chain-length polyhydroxyalkanoates (mcl-PHAs). To reduce the substrate cost, which represents nearly 50% of the total PHA production cost, xylose, a hemicellulose derivate, was tested as the growth carbon source in an engineered P. putida KT2440 strain. The genes encoding xylose isomerase (XylA) and xylulokinase (XylB) from Escherichia coli W3110 were introduced into P. putida KT2440. The recombinant KT2440 exhibited a XylA activity of 1.47 U and a XylB activity of 0.97 U when grown on a defined medium supplemented with xylose. The cells reached a maximum specific growth rate of 0.24 h-1 and a final cell dry weight (CDW) of 2.5 g L-1 with a maximal yield of 0.5 g CDW g-1 xylose. Since no mcl-PHA was accumulated from xylose, mcl-PHA production can be controlled by the addition of fatty acids leading to tailor-made PHA compositions. Sequential feeding strategy was applied using xylose as the growth substrate and octanoic acid as the
Biosynthesis of medium-chain-length polyhydroxyalkanoates in transgenic Arabidopsis plants expressing the PhaC1 and PhaC2 synthases from Pseudomonas aeruginosa
Here, we report the use of petrochemical aromatic hydrocarbons as a feedstock for the biotechnological conversion into valuable biodegradable plastic polym
Polyhydroxyalkanoate (PHA) is a versatile class of biodegradable and biocompatible biopolyesters accumulated by many bacteria as intracellular carbon storage compound. The largest subclass consists of medium-chain-length (mcl) PHA which has a large potential in medical applications where flexible or elastomeric materials are required. Different extraction and purification methods for mcl-PHA are known to result in variations of polymer purities. In this study it was assessed whether this difference in quality may increase risk of failure of the implant material by enhanced colonization by Gram-negative and Gram-positive model pathogens (Staphylococcus aureus and Escherichia coli curli). Two types of mcl-PHA copolymers, poly(3-hydroxyoctanoate) (PHO) and the less known poly(3-hydroxyundecanoate) (PHUA), were evaluated for an impact of monomeric unit composition and degree of polymer purity on colonization by the model pathogens. It was found that film formation by bacteria on purified PHO and PHUA
Efficient utilization of all available carbons from lignocellulosic biomass is critical for economic efficiency of a bioconversion process to produce renewable bioproducts. However, the metabolic responses that enable Pseudomonas putida to utilize mixed carbon sources to generate reducing power and polyhydroxyalkanoate (PHA) remain unclear. Previous research has mainly focused on different fermentation strategies, including the sequential feeding of xylose as the growth stage substrate and octanoic acid as the PHA-producing substrate, feeding glycerol as the sole carbon substrate, and co-feeding of lignin and glucose. This study developed a new strategy-co-feeding glycerol and lignin derivatives such as benzoate, vanillin, and vanillic acid in Pseudomonas putida KT2440-for the first time, which simultaneously improved both cell biomass and PHA production. Co-feeding lignin derivatives (i.e. benzoate, vanillin, and vanillic acid) and glycerol to P. putida KT2440 was shown for the first time to
Efficient utilization of all available carbons from lignocellulosic biomass is critical for economic efficiency of a bioconversion process to produce renewable bioproducts. However, the metabolic responses that enable Pseudomonas putida to utilize mixed carbon sources to generate reducing power and polyhydroxyalkanoate (PHA) remain unclear. Previous research has mainly focused on different fermentation strategies, including the sequential feeding of xylose as the growth stage substrate and octanoic acid as the PHA-producing substrate, feeding glycerol as the sole carbon substrate, and co-feeding of lignin and glucose. This study developed a new strategy-co-feeding glycerol and lignin derivatives such as benzoate, vanillin, and vanillic acid in Pseudomonas putida KT2440-for the first time, which simultaneously improved both cell biomass and PHA production. Co-feeding lignin derivatives (i.e. benzoate, vanillin, and vanillic acid) and glycerol to P. putida KT2440 was shown for the first time to
Research into the production of biodegradable polymers has been driven by vision for the most part from changes in policy, in Europe and America. These policies have their origins in the Brundtland Report of 1987, which provides a platform for a more sustainable society. Biodegradable polymers are part of the emerging portfolio of renewable raw materials seeking to deliver environmental, social, and economic benefits. Polyhydroxyalkanoates (PHAs) are naturally-occurring biodegradable-polyesters accumulated by bacteria usually in response to inorganic nutrient limitation in the presence of excess carbon. Most of the early research into PHA accumulation and technology development for industrial-scale production was undertaken using virgin starting materials. For example, polyhydroxybutyrate and copolymers such as polyhydroxybutyrate-co-valerate are produced today at industrial scale from corn-derived glucose. However, in recent years, research has been undertaken to convert domestic and ...
A method of recovering polyhydroxyalkanoates (PHAs) from municipal waste sludge includes: (a) measuring a solid content in the municipal waste sludge in terms of a volatile suspended solid in the mun
As the only kind of naturally-occurring biopolyester synthesized by various microorganisms, polyhydroxyalkanoate (PHA) shows a great market potential in packaging, fiber, biomedical, and other fields due to its biodegradablity, biocompatibility, and renewability. However, the inherent defects of scl-PHA with low 3HV or 4HB content, such as high stereoregularity, slow crystallization rate, and particularly the phenomena of formation of large-size spherulites and secondary crystallization, restrict the processing and stability of scl-PHA, as well as the application of its products. Many efforts have focused on the modification of scl-PHA to improve the mechanical properties and the applicability of obtained scl-PHA products. The modification of structure and property together with the potential applications of scl-PHA are covered in this review to give a comprehensive knowledge on the modification and processing of scl-PHA, including the effects of physical blending, chemical structure design, and
SIRIM consortium researchers developed the process technology in 2006 to produce polyhydroxyalkanoates (PHA) polyesters from palm oil wastes. (Image courtesy of SIRIM Berhad.)
TY - JOUR. T1 - Production of medium-chain length polyhydroxyalkanoates by Pseudomonas citronellolis grown in apple pulp waste. AU - Rebocho, Ana Teresa. AU - Pereira, Joao R.. AU - Freitas, Filomena. AU - Neves, Luisa A.. AU - Alves, Vitor D.. AU - Sevrin, Chantal. AU - Grandfils, Christian. AU - Reis, Maria A. M.. N1 - info:eu-repo/grantAgreement/FCT/5876/147258/PT# info:eu-repo/grantAgreement/FCT/5876/147218/PT# info:eu-repo/grantAgreement/FCT/5876/135920/PT# This work was supported by the Unidade de Ciencias Biomoleculares Aplicadas (UCIBIO), Associated Laboratory for Sustainable Chemistry - Clean Processes and Technologies (LAQV) and LEAF-Linking Landscape, Environment, Agriculture and Food, which are financed by national funds from FCT/MEC (UID/Multi/04378/2013, UID/QUI/50006/2013 and PEst-OE/AGR/UI0245/2014, respectively) and co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007728, POCI-01-0145-FEDER-007265, respectively), and exploratory project grants ...
Misra, Superb K., Nazhat, Showan N., Torbati, M.M., Silva, S.R.P., Roy, Ipsita and Boccaccini, Aldo R. (2006) From bacteria to tissue engineering applications-usage of polyhydroxyalkanoates for biomedical applications. In: Proceedings of the International Conference on the Design of Biomaterials, 08 - 11 Dec 2006, Kanpur, India. Full text not available from this repository ...
A single-nucleotide substitution in phasin gene leads to enhanced accumulation of polyhydroxyalkanoate (PHA) in Escherichia coli harboring Aeromonas caviae PHA biosynthetic operonA single-nucleotide substitution in phasin gene leads to enhanced accumulation of polyhydroxyalkanoate (PHA) in Escherichia coli harboring Aeromonas caviae PHA biosynthetic operon ...
The investigation and development of plastics synthesized by bacteria is receiving great attention also due to the raising petroleum prices and many environmental concerns related to plastic pollution. Recent results and studies of the properties and various applications of bio-based plastics are presented in this volume. Polyhydroxyalkanoates (PHAs), a biodegradable compound, is treated in several chapters: PHAs as energy and intracellular carbon storage compounds, the metabolic engineering of PHA producers, the development of tailor-made PHAs including uncommon monomers, microbial PHA production from waste raw materials, PHA polyesters produced by both wild-type and recombinant bacteria and the production of medium-chain-length PHAs in pseudomonads. Further microbial plastics discussed are lactic acid and its polymer polylactic acid (PLA), succinic acid and its polymer polybutylene succinate (PBS), ethylene from ethanol and its polymer polyethylene, 1,3-propandiol as well as poly(p-phenylene) ...
By Renard, E Langlois, V; Guerin, P Polyhydroxyalkanoates (PHAs) form an enlarged family of biopolyesters, which are biocompatible, biodegradable and non- toxic. Polyhydroxyalkanoates biodegradation corresponds to a hydrolysis involving endo- or exo-enzymatic systems in the breaking cleavage of esters bonds. This type of degradation is needed for environmental applications. In the case of therapeutic and biomedical uses, a simple hydrolysis is required. Hydrolytic degradation of PHAs is not evident as shown on poly(3- hydroxyoctanoate) (PHO) and is depending on the structure of the polyester and more particularly on the nature of the side chains. In some cases, blending with others polymers has decreased PHAs crystallinity and has made easier hydrolysis. Another route consists in the preparation of unsaturated PHAs which can be chemically modified. Pendant double bonds have been turned into carboxylic, hydroxyl or epoxy groups. Moreover these reactive functions were used for grafting oligomers ...
View more ,The class II PHA (polyhydroxyalkanoate) synthases [PHAMCL synthases (medium-chain-length PHA synthases)] are mainly found in pseudomonads and catalyse synthesis of PHAMCLs using CoA thioesters of medium-chain-length 3-hydroxyfatty acids (C6-C14) as a substrate. Only recently PHAMCL synthases from Pseudomonas oleovorans and Pseudomonas aeruginosa were purified and in vitro activity was achieved. A threading model of the P. aeruginosa PHAMCL synthase PhaC1 was developed based on the homology to the epoxide hydrolase (1ek1) from mouse which belongs to the α/β-hydrolase superfamily. The putative catalytic residues Cys-296, Asp-452, His-453 and His-480 were replaced by site-specific mutagenesis. In contrast to class I and III PHA synthases, the replacement of His-480, which aligns with the conserved base catalyst of the α/β-hydrolases, with Gln did not affect in vivo enzyme activity and only slightly in vitro enzyme activity. The second conserved histidine His-453 was then replaced by ...
In this work, sludge was submitted to aerobic dynamic substrate feeding. Two sequencing batch reactors were operated, with acetate or propionate as carbon substrates. When acetate was used the system only produced a homopolymer of polyhydroxybutyrate (PHB). In order to maximize the PHB production, tests with different concentrations of acetate and ammonia were preformed. The best results (67.2% of PHB by cell dry weight) were obtained for 0.7 Nmmol/l of ammonia and 180 Cmmol/l of acetate. The PHB cell content was further improved by pupulse addition of substrate, three times 60 Cmmol/l of acetate, reaching a value of 78.5%. Propionate can be used as a precursor for hydroxyvalerate. In conjunction with other substrates, it allows for the formation of copolymers, which present better processing properties on commercial applications. Tests with different concentrations of propionate and ammonia were performed. Under the operating conditions used, the maximum PHA accumulated inside cells was 34.8%, ...
Introduction. Polyhydroxyalkanoates (PHA) are bio-polymeric materials that exhibit excellent biodegradability and biocompatibility. These biodegradable polymers possess excellent physico-mechanical properties resulting in their current increase in diverse applications. In fact they are commonly utilized in various biomedical applications spanning from drug delivery devices to tissue engineering scaffoldings (Francis, 2011).. These polymers are accumulated in vivo as cellular inclusions and serve as carbon source reserves in several bacterial species (Xue et al., 2010; Hofer et al., 2011; Gumel et al., 2012b). Among the most extensively studied bacterial species capable of accumulating these biopolymers are those belonging to genus Pseudomonas reported to accumulate intracellular PHA under limited nutrient conditions and abundant carbon source such as fatty acids (Annuar et al., 2007; Gumel, et al., 2013).. For a successful process optimization, acquisition of process kinetics information ...
In order to facilitate the large-scale preparation of active class II polyhydroxyalkanoate (PHA) synthase, we constructed a vector pT7-7 derivative that contains a modified phaC1 gene encoding a PHA synthase from Pseudomonas aeruginosa possessing six N-terminally fused histidine residues. Overexpression of this phaC1 gene under control of the strong Ø10 promoter was achieved in Escherichia coli BL21(DE3). The fusion protein was deposited as inactive inclusion bodies in recombinant E. coli, and contributed approx. 30% of total protein. The inclusion bodies were purified by selective solubilization, resulting in approx. 70-80% pure PHA synthase, then dissolved and denatured by 6M guanidine hydrochloride. The denatured PHA synthase was reversibly immobilized on a Ni2+-nitrilotriacetate-agarose matrix. The matrix-bound fusion protein was refolded by gradual removal of the chaotropic reagent. This procedure avoided the aggregation of folding intermediates which often decreases the efficiency of ...
A newly isolated mutation (Gln508Leu) and a combination of it with previously discovered beneficial mutations in polyhydroxyalkanoate synthase 1 from Pseudomonas sp. 61-3 were found to enhance the production of poly(3-hydroxybutyrate) [P(3HB)] and poly(3HB-co-3-hydroxyalkanoate)s in recombinant Esch …
Production of polyhydroxyalkanoates (PHAs) in activated sludge treating wastewater represents an economical and environmental promising alternative to pure culture fermentations. A process for production of PHA from a paper mill wastewater was examined at laboratory scale. The three stage process examined consisted of acidogenic fermentation to convert wastewater organic matter to volatile fatty acids (VFAs), an activated sludge system operating under feast/famine conditions to enrich for PHA producing organisms and accumulation of PHA in batch experiments. After fermentation of the wastewater, 74% of the soluble COD was present as VFA (acetate, propionate, butyrate and valerate) and the resulting PHA after batch accumulation consisted of 31-47 mol% hydroxybutyrate and 53-69 mol% hydroxyvalerate. The maximum PHA content achieved was 48% of the sludge dry weight and the three stage process exhibited a potential to produce 0.11 kg of PHA per kg of influent COD treated ...
Degradation of polyhydroxyalkanoate (PHA) by three Pseudomonas spp., isolated from fuel-oil contaminated soil and identified as Ps. fluorescens, Ps. aeruginosa and Ps. putida on the basis of 16S rRNA sequence analysis, was investigated. Degradation of PHAs was determined as molecular weight loss measured by gel permeation chromatography and morphological changes in poly-3-hydroxybutyrate films observed by scanning electron microscopy. Both, decrease in molecular weight (7-17%) and weight loss (up to 29%) of solution-cast films were evidence of the isolates secreting an active depolymerase responsible for degradation of PHA. The kinetic parameters, V-max and Km, for depolymerase activity of Ps. aeruginosa in the presence of p-nitrophenylbutyrate as substrate were determined to be 2.8 mumol min(-1) and 2.8 mM, respectively, in 50 mM phosphate buffer, pH 7.9, at 30degreesC. Stimulation of activity by Na+, K+, Ca2+ and Mg2+ at 1 mM concentration indicated a requirement for metal ions as a cofactor ...
The gene encoding a 4-hydroxybutyryl-Co A transferase has been isolated from bacteria and integrated into the genome of bacteria also expressing a polyhydroxyalkanoate synthase, to yield an improved p
Polyhydroxyalkanoates (PHA) [1] are natural thermoplastics synthesized by many microorganisms as an intracellular storage material under unbalanced conditions of growth. As a substitute, to synthetic petrochemical polymers as well as to fulfill the growing demand of environmentally friendly plastics, production of PHA is under intensive studies [2]. PHA belong to a family of fully biodegradable polymers with no toxicity which can also be used for medical applications [3, 4]. PHA can be completely bio-degraded into oligomers and monomers and then to CO2 and water, all are environmentally benign [5-7]. Some PHA have been developed for various applications including bioplastics for packaging, implant materials, biofuels and fine chemicals [8-10].. On the basis of monomer structures, PHA are divided into short chain length (scl) polymers consisting of monomers of C3-C5 carbon atoms, medium chain length (mcl) polymers consisting of monomers of C6-C16 carbons atoms, as well as PHA copolymers ...
Polyhydroxyalkanoates are a class of over 80 polyesters synthesized by more than 300 microorganisms that exhibit material properties similar to those of petrochemical plastics (Lee, 1999; Lee, 1996). Polyhydroxybutyrate (PHB), the most prevalent PHA, has been of particular interest in commercial and medical applications because of its high tensile strength, biodegradability, and biocompatibility with human tissues (Lee, 1996b; Abe, 1992; Williams 2002). Concerns with the increasingly limited supply of fossil fuels and public anxiety over landfills oversaturated with non-biodegradable materials have also stimulated bioplastic research (Moran, 2006; Ojumu, 2004). PHA research has increased in an effort to understand its potential. It has been used for specialized medical applications, including bone fixation, drug delivery systems and degradable sutures (Knowles, 1993: Kose, 2004; Holmes, 1985: Chen, 2005). ...
Large-scale production and purification of recombinant proteins by cell cultures represent a key-area in manufacturing field. The production process still has several drawbacks affecting cost/efficiency. In this work, three modular systems were designed to overcome some of these bottlenecks. A library of self-inducible promoters was built and characterized to start the peptide production at a desired culture density, without expensive inducer molecules. Two standard integrative vectors were realized to insert BioBrick parts in user-defined positions of E. coli or S. cerevisiae genome, to ensure genetic stability without using selection markers. Finally, two promising techniques were combined for an in-cell protein purification: PolyHydroxyAlkanoate (PHA) granules were used as a substrate for PHA-binding peptides (Phasins) fused to the target protein, thus replacing affinity resins/columns and tags, while a pH-based self-cleaving peptide (Intein) was used instead of a protease cleavage site. ...
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Bio-on and SECI Spa, part of Gruppo Industriale Maccaferri holding, signed an agreement to build the worlds first facility for the production of PHAs bioplastic from biodiesel production co-products, namely glycerol. The two companies will work together to build a production site with a 5 thousand tons/year output, expandable to 10 thousand tons/year. Requiring a 55…
Single-use plastic is a growing problem for our planet. Now, one student has created a bioplastic using an unconventional material - fish skins and scales.
مقدمه: فیتاز، فیتیک‌اسید را هیدرولیز می‌کند و دسترسی زیستی فسفر و دیگر مواد معدنی مغذی را برای حیوانات تک‌معده‌ای افزایش می‌دهد.بنابراین، به‌شکل افزودنی غذایی مهم استفاده می‌شود. مواد و روش‏‏ها: هدف مطالعه حاضر، جداسازی باکتری‌‌های تولیدکننده فیتاز از مزرعه لوبیای شوشتر، جنوب‌غرب ایران، با استفاده از محیط غربال‌گری فیتاز (PSM) و بهینه‌سازی رشد و شرایط تولید آنزیم با بهترین جدایه است. نتایج: بهترین جدایه، سیتروباکتر فارمری سویه phas32 شناسایی شد. دمای 30 درجه سانتی‌گراد، اسیدیته 7، 25/0 درصد فیتیک‌اسید و 48 ساعت انکوباسیون، شرایط بهینه‌سازی‌شده برای
Fe-Zr oxides with different Zr/Fe molar ratios were prepared by a co-precipitation method and used as catalysts for the vapor phas... ...
Ralstonia eutropha H16 is a well-studied bacterium with respect to biosynthesis of polyhydroxyalkanoates (PHAs), which has attracted attentions as biodegradable bio-based plastics. However, this strain shows quite poor growth on glycerol of which bulk supply has been increasing as a major by-product of biodiesel industries. This study examined enhancement of glycerol assimilation ability of R. eutropha H16 by introduction of the genes of aquaglyceroporin (glpF) and glycerol kinase (glpK) from Escherichia coli. Although introduction of glpFK Ec into the strain H16 using a multi-copy vector was not successful, a recombinant strain possessing glpFK Ec within the chromosome showed much faster growth on glycerol than H16. Further analyses clarified that weak expression of glpK Ec alone allowed to establish efficient glycerol assimilation pathway, indicating that the poor growth of H16 on glycerol was caused by insufficient kination activity to glycerol, as well as this strain had a potential ability ...
The synthesis and degradation of polyhydroxyalkanoates (PHAs), the storage polymer of many bacteria, is linked to the operation of central carbon metabolism. To rationalize the impact of PHA accumulation on central carbon metabolism of the prototype bacterium Pseudomonas putida, we have revisited PHA production in quantitative physiology experiments in the wild-type strain vs. a PHA negative mutant growing under low nitrogen conditions. When octanoic acid was used as PHA precursor and as carbon and energy source, we have detected higher intracellular flux via acetyl-CoA in the mutant strain than in the wild type, which correlates with the stimulation of the TCA cycle and glyoxylate shunt observed on the transcriptional level. The mutant defective in carbon and energy storage spills the additional resources, releasing CO2 instead of generating biomass. Hence, P. putida operates the metabolic network to optimally exploit available resources and channels excess carbon and energy to storage via PHA, ...
TY - JOUR. T1 - Isolation of polyhydroxyalkanoate from hydrolyzed cells of Bacillus flexus using aqueous two-phase system containing polyethylene glycol and phosphate. AU - Divyashree, M. S.. AU - Shamala, T. R.. AU - Rastogi, N. K.. PY - 2009/10/9. Y1 - 2009/10/9. N2 - Main objective of present work was to isolate polyhydroxyalkanoate (PHA) from cell lysate of Bacillus flexus by aqueous-aqueous two-phase system (ATPS). Selected ATPS having polyethylene glycol (12%, w/v) and potassium phosphate (9.7%, pH 8.0) containing cell lysate obtained by sonication or hypochlorite treatment of B. flexus biomass (1 g%, dry weight), was held at 28°C for 30 min, which partitioned PHA into top PEG phase and residual cell materials into bottom phase. For enzymatic cell hydrolysis, Microbispora sp. culture filtrate having protease (3 U/mL) was mixed with B. flexus biomass and ATPS, incubated at 37°C for 2 h prior to phase separation. PHA recovered by centrifugation was 19∼51% of cell dry weight, depending on ...
de Eugenio, L.I., García, P., Luengo, J.M., Sanz, J., San Román, J., García, J.L., and Prieto, M.A. (2007) Biochemical evidence that phaZ gene encodes a specific intracellular medium chain length polyhydroxyalkanoate depolymerase in Pseudomonas putida KT2442: characterization of a paradigmatic enzyme. J Biol Chem 282: 4951-4962 ...
Achieving a sustainable society requires, among other things, the use of renewable feedstocks to replace chemicals obtained from petroleum-derived compounds. Crude glycerol synthesized inexpensively as a byproduct of biodiesel production is currently considered a waste product, which can potentially be converted into value-added compounds by bacterial fermentation. This study aimed at evaluating several characterized P. putida strains to produce medium-chain-length poly(3-hydroxyalkanoates) (mcl-PHA) using raw glycerol as the only carbon/energy source. Among all tested strains, P. putida KT2440 most efficiently synthesized mcl-PHA under nitrogen-limiting conditions, amassing more than 34% of its cell dry weight as PHA. Disruption of the PHA depolymerase gene (phaZ) in P. putida KT2440 enhanced the biopolymer titer up to 47% PHA (%wt/wt). The low biomass and PHA titer found in the mutant strain and the wild-type strain KT2440 seems to be triggered by the high production of the side-product citrate during
1.Chen GQ, Wu Q. 2005. The application of polyhydroxyalkanoates as tissue engineering materials. Biomaterials. 26:6565-6578 2. Doi Y, Kunioka M, Nakamura Y, Soga K. 1986. Nuclear magnetic resonance studies on poly(B-hydroxybutyrate) and a copolyester of B-hydroxybutyrate and B-hydroxyvalerate isolated from Alcaligenes eutrophus H16. Macromolecules. 19:2860-2864 3. Endy D. 2005. Foundations for engineering biology. Nature. 438(7067):449-53 4. International Genetically Engineered Machines competition. 15 Jun 2008. 26 Jul 2008. ,http://igem.org, 5. Holmes PA. 1985. Applications of PHB - a microbially produced biodegradable thermoplastic. Physics in technology. 16:32-36 6. Kang Z, Wang Q, and H Zhang. 2008. Construction of a stress-induced system in Escherichia coli for efficient polyhydroxyalkanoates production. Biotechnological Products and Process Engineering. 79:203-208 7. Knight TF. 2003. Idempotent Vector Design for Standard Assembly of BioBricks. Tech. rep., MIT Synthetic Biology Working ...
AB - The polyhydroxyalkanoates (PHAs) are microbially-produced biopolymers that could potentially be used as sustainable alternatives to oil-derived plastics. However, PHAs are currently more expensive to produce than oil-derived plastics. Therefore, more efficient production processes would be desirable. Cell-free metabolic engineering strategies have already been used to optimise several biosynthetic pathways and we envisioned that cell-free strategies could be used for optimising PHAs biosynthetic pathways. To this end, we developed several Escherichia coli cell-free systems for in vitro prototyping PHAs biosynthetic operons, and also for screening relevant metabolite recycling enzymes. Furthermore, we customised our cell-free reactions through the addition of whey permeate, an industrial waste that has been previously used to optimise in vivo PHAs production. We found that the inclusion of an optimal concentration of whey permeate enhanced relative cell-free GFPmut3b production by ∼50%. In ...
A new bacterium, designated as strain TE9 was isolated from a microbial mat in French Polynesia and was studied for its ability to synthesize medium chain length poly-beta-hydroxyalkanoates (mcl PHAs) during cultivation on cosmetics co-products. The composition of PHAs was analysed by coupled gas chromatography mass spectroscopy (GC/MS), nuclear magnetic resonance (NMR) and Fourier Transform InfraRed (FTIR) spectroscopy. PHAs were composed of C6-C14 3-hydroxyacids monomers, with a predominance of 3-hydroxyoctanoate (3HO), 3-hydroxydecanoate (3HD) and 3-hydroxydodecanoate (3HDD). Differential scanning calorimetry (DSC) experiments allowed the characterization of elastomeric materials with a melting point T(m) near 50 degrees C, enthalpy of fusion DeltaH(m) from 27 to 32 J/g, and glass transition temperature T(g) of -43 degrees C. Molecular weights ranged from 175,000 to 358,000 g/mol. On the basis of the phenotypical features and genotypic investigations, strain TE9 was assigned to the Pseudomonas genus
Domain architectures containing the following SCOP superfamilies _gap_,100950,_gap_ in Pseudomonas mendocina NK-01. Domain architectures illustrate each occurrence of _gap_,100950,_gap_.
In California, researchers at the University of California, Berkeley have coaxed Escherichia coli to use fluorinated building blocks to make new organofluorine target molecules.. Led by with Michelle C.Y. Chan, the group able to introduce genes to code for enzymes that use fluorine-containing derivatives of their normal substrates. The researchers also introduced a gene for an enzyme used by many bacteria to make polyhydroxyalkanoates (PHAs), a biodegradable bioplastic. The fluorinated versions of PHA were less brittle than conventional PHAs, opening up new applications. The researchers also hope to produce small fluorinated molecules in living cells for pharmaceuticals. ...
Caracterización de la fasina PhaF de Pseudomonas putida KT2442 y de su unión a polímeros de poli-3-hidroxibutirato Conference Paper 2008 ...
Abstract: Poly (3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) is one of the components of polyhydroxyalkanoates (PHAs) and some of its mechanical properties have been shown to improve over poly (3-hydroxybutyrate) (PHB) and poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). The investigation of PHBHHx microspheres as a drug delivery system was prepared by emulsion-solvent evaporation method for the sustained release of anti-cancer drug 5-fluorouracil (5-FU) and cyclosporin A (CsA). The mean diameter of the PHBHHx microspheres ranged from 5.24 to 22.10 μm dependent on the different processing parameters. The PHBHHx concentration, emulsifier concentration, anti-cancer drug dosage, and agitation speed, were optimized according to the encapsulation efficiency of 4% PHBHHx, 0.5% SDS, 10 mg anti-cancer drug, and 500 rpm. Under optimized conditions, the encapsulation efficiency of 5-FU and CsA microspheres were 7.19% and 96.44%, respectively. The morphologies of scanning electron microscope ...
23. The norbornene polymer according to claim 8, wherein the norbornene polymer is a copolymer further comprising a polar norbornene repeating unit represented by Formula 3 and a nonpolar norbornene repeating unit represented by Formula 4:wherein each m is independently an integer of 0 to 4,at least one of R1a, R2a, R3a, and R4a is a polar functional group containing at least one atom selected from the group consisting of oxygen, nitrogen, phosphorus, sulfur, silicon, and boron, andR1a, R2a, R3a, and R4a that are not the polar functional group are each independently hydrogen; halogen; linear or branched alkyl, alkenyl, or vinyl having 1 to 20 carbon atoms; cycloalkyl that is unsubstituted or substituted with hydrocarbon and has 5 to 12 carbon atoms; aryl that is unsubstituted or substituted with hydrocarbon and has 6 to 40 carbon atoms; aralkyl that is unsubstituted or substituted with hydrocarbon and has 7 to 15 carbon atoms; alkynyl that has 2 to 20 carbon atoms; linear or branched haloalkyl, ...
The bio-transformation of organic crops, such as corn, has led to a range of polyesters such as poly lactic acid (PLA) and polyhydroxyalkanoates (PHA). ). Applications of these polyesters could include paper coatings, wood product finishing, adhesives, and waterborne coating technologies. Researchers at UNH are preparing waterborne hybrid vinylic polyester latices through a miniemulsion polymerization process ...
Some of the top companies like Asta Real and Fuji Health have doubled its production capacity recently owing to the increasing demand of astaxanthin.. Lutein, a carotenoid extracted from algae, is capable of preventing the onset of Age-related Macular Degeneration (AMD). The global market value of lutein was around $233 million in 2010 and is expected to reach $309 million by 2018.. Algae are also widely used in the production of enzymes and toxins which, in general, have a product values in the range of US $4000-8000/kg. Algae are also used in cosmetics industry as thickening agents, water-binding agents and antioxidants.. Algae based added value commodities such as lactic acid, polyhydroxyalkanoates and butanol price ranges from US $1300 to US $7000/tonne.. Learn more on the business opportunities in algae non-fuel products from Comprehensive Report on Attractive Algae Product Opportunities. ...
The results of the stereolithographic habitat construction process of Cesaretti et al. [11] can also be accomplished with a three-dimensional printer that extrudes plastic media using fused deposition modelling (FDM). A comparison of the different additive manufacturing methods and possible feedstocks is included in [49], which explains why FDM is preferred over stereolithography for space applications. To determine the existence of launch mass savings for three-dimensional printed habitats from biological processes, this section examines the extraterrestrial manufacture of feasible three-dimensional printer raw materials like polyhydroxyalkanoate (PHA) biopolymers, of which polyhydroxybutyrates (PHBs) are an example. A contrast of habitat structural properties when using either salt-MgO or biopolymers as printer media is beyond the scope of this paper.. The biomanufacture of PHAs is reviewed in [122-125], and Lu et al. [123] include a list of organisms known to synthesize PHAs. It has been ...
Its time to talk about something that almost everyone can use without being worried about breaking out. AHAs and BHAs are fantastic chemical exfoliants but weve heard way too many cases of people breaking out or purging periods being too long. Fear no more ladies for its time to welcome PHAs into our lives. So, what
A process for producing a toner for developing electrostatic images is disclosed. A polymerizable monomer composition is first prepared and dispersed in an aqueous medium by the action of high shear force to produce particles. The polymerizable monomer is then polymerized in a container having a jacket. The liquid temperature inside the container is controlled by feeding a high-pressure vapor into the jacket while adjusting the degree of vacuum inside the jacket. The production process can achieve a superior temperature response, can keep the reaction system at a constant temperature with ease and can realize shortened production time and reduced production cost.
Supplementary MaterialsSupplementary Info 41598_2019_39321_MOESM1_ESM. of promoter engineering for raising the produce of mcl-PHA in NK-01. In this ongoing work, 10 endogenous promoters from NK-01 had been identified predicated on promoter and RNA-seq prediction outcomes. Subsequently, 10 putative promoters had been characterized for his or her power through the manifestation of the reporter gene operon in the genome of NK-01, leading to the recombinant strains NKU-4C1, NKU-16C1 and NKU-6C1. Needlessly to say, the transcriptional degrees of and in the recombinant strains had been increased as demonstrated by real-time quantitative RT-PCR. The gene encoding PHA depolymerase was erased to create the recombinant strains NKU- further?NK-01 and highlights the potential of the screened endogenous solid promoters for metabolic executive of NK-01 to improve the produce of mcl-PHA. Intro Currently, promoter executive can serve as a robust tool for logical tuning of the experience of the artificial ...
Metabolix biopolymers are based on polyhydroxyalkanoate polymers (PHAs) and are made by fermentation.. using renewable carbon based feedstocks, making them 100% biobased in neat form.. ...
Large-scale production and purification of recombinant proteins by cell cultures represent a key-area in manufacturing field. The production process still has several drawbacks affecting cost/efficiency. In this work, three modular systems were designed to overcome some of these bottlenecks. A library of self-inducible promoters was built and characterized to start the peptide production at a desired culture density, without expensive inducer molecules. Two standard integrative vectors were realized to insert BioBrick parts in user-defined positions of E. coli or S. cerevisiae genome, to ensure genetic stability without using selection markers. Finally, two promising techniques were combined for an in-cell protein purification: PolyHydroxyAlkanoate (PHA) granules were used as a substrate for PHA-binding peptides (Phasins) fused to the target protein, thus replacing affinity resins/columns and tags, while a pH-based self-cleaving peptide (Intein) was used instead of a protease cleavage site. ...
Record removed. The sequence NP_745242 is 100% identical to WP_003248355.1 over its full length. Be aware that a NCBI nonredundant RefSeq protein (WP_) can be annotated on large numbers of bacterial genomes that encode that identical protein.. Old NP_745242.1 New WP_003248355.1 Identical proteins Re-annotation project. ...
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If he chooses to use only Styrofoam items (which weighs much less than PLA and plastic items) - in one year, he will have consumed 191.11 kWh of energy, released 95.81 pounds of CO2 and used 254.59 gallons of water. Since the average household uses 29.19 kWh of energy per day, this would be enough energy to power a household for 6.55 days ...
Richée Professional Bioplastic Progressive Brush reduces the volume of undisciplined and rebellious hair. Its formula, enriched with highly nutritious ingredients, will leave your hair smooth and with a renewed structure.Professional Bioplastic Richée restores moisture to the hair fiber, essential for the health and mo
Proposed maintenance/housekeeping building; gas storage compound; staff car parking; temporary lodge storage area Ref P/01428/14 TCP/20245/ ...
chains in the Genus database with same CATH superfamily 3C1Y A; 4Z6D A; 1KFD A; 5D49 A; 4I2I A; 3MR2 A; 4YMO A; 3GII A; 2BPF A; 1T7P A; 4PHA A; 4RNN A; 4QWC A; 4CCH A; 1ARO P; 1ZQK A; 5KFB A; 3MFH A; 5HP4 A; 5KT3 A; 1Z00 B; 4YVZ A; 3KHH A; 3THV A; 3RBE A; 3RJK A; 2J6T A; 1SKR A; 1MQ3 A; 4YXM A; 1U47 A; 5J2H A; 4Q45 A; 2H5X A; 4UAZ A; 2XY6 A; 3LDA A; 5KFE A; 4J9L A; 5DB9 A; 3KHR A; 2Y1J A; 2MUT B; 9ICP A; 3C1Z A; 2GWS A; 3MBY A; 3BDP A; 4FBU A; 4DSL A; 1SL2 A; 5CP2 A; 4DQP A; 2DFL A; 2VA8 A; 3BQ0 A; 5CHG A; 4XRH A; 1SL1 A; 3RJG A; 3OHA A; 4JK1 A; 9ICT A; 2I1Q A; 4C8O A; 3RRH A; 2ASD A; 1QSY A; 2W8L A; 2R8H A; 2Y1I A; 3HPO A; 1BPY A; 2PFO A; 2ZUC A; 3V7J A; 2HHX A; 2KZZ A; 1QLN A; 4UB5 A; 1K1Q A; 3V7K A; 1T4G A; 4ZH4 A; 5J2K A; 2R8I A; 3UXP A; 4PPX A; 4MF2 A; 4O3O A; 3ETL A; 4F91 B; 5J0R A; 1TK0 A; 4RNO A; 4RQ0 A; 2MUT A; 4TUR A; 3TFR A; 1ZQA A; 1D9F A; 4P4M A; 3MGI A; 3ZDA A; 4QZA A; 4GC6 A; 3FYH A; 5KFC A; 4ECZ A; 3T3F A; 3C5G A; 2PI5 A; 4YFK A; 9ICK A; 7ICV A; 4UB3 A; 2NRZ A; 3C23 A; 4NLG A; ...
He is clean necked, big hipped and has a killer look when you study him from the profile.. Hair like a carrier, but is THF and PHAF to breed to your carrier cows.. Winning is in his pedigree, as his dam is the full sister to the dam of the 2015 NWSS grand champion steer.. ...
Every month, a womans body prepares itself for the possibility of conception and pregnancy by going through a menstrual cycle. During the menses phas...
Genentech, a member of the Roche Group (SIX: RO, ROG; OTCQX: RHHBY) today announced positive topline results from two identically designed global Phas
Can you name the Phar 401 Druglist Test your knowledge on this science quiz to see how you do and compare your score to others. Quiz by mpchiang
Study Phar1603 using smart web & mobile flashcards created by top students, teachers, and professors. Prep for a quiz or learn for fun!
Visiongain publishes insightful market-led reports that will help you understand future opportunities from changes in technologies, materials & regulations.
Visiongain publishes insightful market-led reports that will help you understand future opportunities from changes in technologies, materials & regulations.