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Kumar Sudesh - One of the best experts on this subject based on the ideXlab platform.
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The Potential Application of Cupriavidus Necator as Polyhydroxyalkanoates Producer and Single Cell Protein: A Review on Scientific, Cultural and Religious Perspectives
2019Co-Authors: Jiun Yee Chee, Manoj Lakshmanan, Iffa Farahin Jeepery, Nabila Husna Mohamad Hairudin, Kumar SudeshAbstract:Background and objective: Polyhydroxyalkanoates are environmentally friendly bioplastic compounds produced via the microbial route that offer an alternative to synthetic plastics due to their comparable durability and thermal stability. However, the high production cost as a result of carbon feedstock for microorganisms and the downstream recovery process narrow the usage of polyhydroxyalkanoates in various fields. Conversion of by products from the food and agricultural industries such as waste cooking oil, glycerol, palm sludge oil, oil palm trunk sap and soya waste into polyhydroxyalkanoates is an attractive approach that can minimize and/or add value to waste. Results and conclusion: Recently, there has been a lot of interest in exploring not just polyhydroxyalkanoates as valued-added products, but also PHA-producing bacteria as a nutritional food or feed source. It has been previously reported that the PHA-producing bacterium, Cupriavidus Necator , can be utilized as a single cell protein (SCP) in animal feed owing to its high protein content. The mealworm beetle ( Tenebrio molitor ) has also been used as the model insect to evaluate the efficacy of Cupriavidus Necator cells as a source of protein and to recover polyhydroxyalkanoate granules at the same time. The European Union has imposed strict regulations on the type of feedstock that can be used to ensure that the food chain is safe. In addition, there are religious and cultural concerns. This review will focus on the nutritional value of Cupriavidus Necator as single cell protein and its safety as animal feed. The impact of using by-products from the agriculture and food industries as carbon feedstocks to produce single cell protein will be discussed, alongside societal acceptance of this practice. Conflict of interest: The authors declare no conflict of interest.
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biological recovery and properties of poly 3 hydroxybutyrate from Cupriavidus Necator h16
Separation and Purification Technology, 2017Co-Authors: Balakrishnan Kunasundari, Carlos Rodriguez Arza, Frans H J Maurer, Vikneswaran Murugaiyah, Gurjeet Kaur, Kumar SudeshAbstract:Abstract In the present study, we observed that laboratory rats readily consumed lyophilized cells of Cupriavidus Necator H16 cultivated using palm oil containing 39 wt% poly(3-hydroxybutyrate) [P(3HB)] as sole diet source. The test animals excreted whitish fecal pellets containing 82–97 wt% P(3HB). The remaining impurities could be easily removed by washing the pellets with water and/or low concentrations of detergent, which resulted in P(3HB) granules of a high purity. The molecular masses and thermal properties of P(3HB) obtained by this method were almost similar to P(3HB) extracted from bacterial cells using chloroform. The method reported here is simple and eliminates the need for solvents and strong chemicals, thus resulting in P(3HB) production that is more ecofriendly.
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biosynthesis and characterization of novel polyhydroxyalkanoate polymers with high elastic property by Cupriavidus Necator phb 4 transformant
Polymer Degradation and Stability, 2010Co-Authors: Kimhou Chia, Azusa Saika, Takeharu Tsuge, Kumar SudeshAbstract:Abstract We attempted to synthesize novel polyhydroxyalkanoate (PHA) containing new 3-hydroxy-4-methylvalerate (3H4MV) monomer from the transformed strain of Cupriavidus Necator PHB−4 harboring the PHA synthase gene of Chromobacterium sp. USM2 (phaCCs). Novel PHA containing SCL and MCL monomers were successfully synthesized from crude palm kernel oil (CPKO) and isocaproic acid. Results showed that P(3HB-co-1 mol% 3HV-co-3 mol% 3H4MV-co-18 mol% 3HHx) possessed higher thermal stability, higher elastomeric behavior at room temperature and higher ductility than the P(3HB-co-5 mol% 3HHx). The novel PHA film was found to possess an interesting rubber-like elasticity and flexibility property which has not been reported. The soil surface degradation study showed that the novel PHA film was degraded faster than the 3HB homopolymer and copolymer with 5 mol% of 3HHx.
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Biosynthesis and characterization of novel polyhydroxyalkanoate polymers with high elastic property by Cupriavidus Necator PHB−4 transformant
Polymer Degradation and Stability, 2010Co-Authors: Kimhou Chia, Azusa Saika, Takeharu Tsuge, Kumar SudeshAbstract:Abstract We attempted to synthesize novel polyhydroxyalkanoate (PHA) containing new 3-hydroxy-4-methylvalerate (3H4MV) monomer from the transformed strain of Cupriavidus Necator PHB−4 harboring the PHA synthase gene of Chromobacterium sp. USM2 (phaCCs). Novel PHA containing SCL and MCL monomers were successfully synthesized from crude palm kernel oil (CPKO) and isocaproic acid. Results showed that P(3HB-co-1 mol% 3HV-co-3 mol% 3H4MV-co-18 mol% 3HHx) possessed higher thermal stability, higher elastomeric behavior at room temperature and higher ductility than the P(3HB-co-5 mol% 3HHx). The novel PHA film was found to possess an interesting rubber-like elasticity and flexibility property which has not been reported. The soil surface degradation study showed that the novel PHA film was degraded faster than the 3HB homopolymer and copolymer with 5 mol% of 3HHx.
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evaluation of jatropha oil to produce poly 3 hydroxybutyrate by Cupriavidus Necator h16
Polymer Degradation and Stability, 2010Co-Authors: Kosin Ng, R Shenbagarathai, Kumar SudeshAbstract:Jatropha oil, a non-edible vegetable oil, may be an alternative substrate to food-grade oils for bioplastic production. Jatropha oil contains 93.9% palmitic acids, oleic acids and linoleic acids. High P(3HB) accumulation of 87 wt% from 13.1 g/L of cell dry weight (CDW) was obtained by Cupriavidus Necator H16 when 12.5 g/L of jatropha oil and 0.54 g/L of urea were used. Lipase activity increased in the initial stages ofP(3HB) production, when 1 g/L ofjatropha oil was added to the preculture medium. Addition of oil in preculture did not affect final CDW or P(3HB) accumulation. P(3HB) production in a 10 L lab-scale fermenter gave a yield of 0.78 g P(3HB) per g jatropha oil used after 48 h. For the first time, this study proved that jatropha oil is a feasible and excellent carbon source for P(3HB) biosynthesis by C. Necator H16 with potential for large-scale production. The toxins in jatropha oil did not affect the P(3HB) biosynthesis.
Iza K. Radecka - One of the best experts on this subject based on the ideXlab platform.
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Production of polyhydroxyalkanoates from waste frying oil by Cupriavidus Necator
AMB Express, 2011Co-Authors: Rob A.j. Verlinden, Zofia Piotrowska-seget, Melvin A. Kenward, David J. Hill, Craig D. Williams, Iza K. RadeckaAbstract:Polyhydroxyalkanoates (PHAs) are biopolymers, which can replace petrochemical plastics in many applications. However, these bioplastics are currently far more expensive than petrochemical plastics. Many researchers are investigating the use of inexpensive substrates derived from waste streams. Waste frying oil is abundant and can be used in PHA production without filtration.Cupriavidus Necator (formerly known as Ralstonia eutropha) is a versatile organism for the production of PHAs. Small-scale batch fermentation studies have been set up, using different concentrations of pure vegetable oil, heated vegetable oil and waste frying oil. These oils are all rapeseed oils.It has been shown that Cupriavidus Necator produced the homopolymer polyhydroxybutyrate (PHB) from the rapeseed oils. The achieved PHB concentration from waste frying oil was 1.2 g/l, which is similar to a concentration that can be obtained from glucose. The PHB harvest from pure oil and heated oil was 0.62 g/l and 0.9 g/l respectively. A feed of waste frying oil could thus achieve more biopolymer than pure vegetable oil. While the use of a waste product is beneficial from a life-cycle perspective, PHB is not the only product that can be made from waste oil. The collection of waste frying oil is becoming more widespread, making waste oil a good alternative to purified oil or glucose for PHB production.
Markus Nett - One of the best experts on this subject based on the ideXlab platform.
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Algae induce siderophore biosynthesis in the freshwater bacterium Cupriavidus Necator H16.
Biometals, 2018Co-Authors: Colette Kurth, Ina Wasmuth, Thomas Wichard, Georg Pohnert, Markus NettAbstract:Cupriachelin is a photoreactive lipopeptide siderophore produced by the freshwater bacterium Cupriavidus Necator H16. In the presence of sunlight, the iron-loaded siderophore undergoes photolytic cleavage, thereby releasing solubilized iron into the environment. This iron is not only available to the siderophore producer, but also to the surrounding microbial community. In this study, the cupriachelin-based interaction between C. Necator H16 and the freshwater diatom Navicula pelliculosa was investigated. A reporter strain of the bacterium was constructed to study differential expression levels of the cupriachelin biosynthesis gene cucJ in response to varying environmental conditions. Not only iron starvation, but also culture supernatants of N. pelliculosa were found to induce cupriachelin biosynthesis. The transcription factors involved in this differential gene expression were identified using DNA–protein pulldown assays. Besides the well-characterized ferric uptake regulator, a two-component system was found to tune the expression of cupriachelin biosynthesis genes in the presence of diatom supernatants.
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Unraveling the predator-prey relationship of Cupriavidus Necator and Bacillus subtilis.
Microbiological Research, 2016Co-Authors: Ivana Seccareccia, Ákos T. Kovács, Ramses Gallegos-monterrosa, Markus NettAbstract:Cupriavidus Necator is a non-obligate bacterial predator of Gram-negative and Gram-positive bacteria. In this study, we set out to determine the conditions, which are necessary to observe predatory behavior of C. Necator. Using Bacillus subtilis as a prey organism, we confirmed that the predatory performance of C. Necator is correlated with the available copper level, and that the killing is mediated, at least in part, by secreted extracellular factors. The predatory activity depends on the nutrition status of C. Necator, but does not require a quorum of predator cells. This suggests that C. Necator is no group predator. Further analyses revealed that sporulation enables B. subtilis to avoid predation by C. Necator. In contrast to the interaction with predatory myxobacteria, however, an intact spore coat is not required for resistance. Instead resistance is possibly mediated by quiescence.
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Structure and biosynthetic assembly of cupriachelin, a photoreactive siderophore from the bioplastic producer Cupriavidus Necator H16
Journal of the American Chemical Society, 2012Co-Authors: Martin F. Kreutzer, Hirokazu Kage, Markus NettAbstract:The bacterium Cupriavidus Necator H16 produces a family of linear lipopeptides when grown under low iron conditions. The structural composition of these molecules, exemplified by the main metabolite cupriachelin, is reminiscent of siderophores that are excreted by marine bacteria. Comparable to marine siderophores, the ferric form of cupriachelin exhibits photoreactive properties. Exposure to UV light induces an oxidation of its peptidic backbone and a concomitant reduction of the coordinated Fe(III). Here, we report the genomics-inspired isolation and structural characterization of cupriachelin as well as its encoding gene cluster, which was identified by insertional mutagenesis. Based upon the functional characterization of adenylation domain specificity, a model for cupriachelin biosynthesis is proposed.
Pavel Zemanek - One of the best experts on this subject based on the ideXlab platform.
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quantitative raman spectroscopy analysis of polyhydroxyalkanoates produced by Cupriavidus Necator h16
Sensors, 2016Co-Authors: Ota Samek, Stanislav Obruca, Martin Siler, Petr Sedlacek, Pavla Benesova, Dan Kucera, Ivana Marova, Jan Ježek, Silva Bernatova, Pavel ZemanekAbstract:We report herein on the application of Raman spectroscopy to the rapid quantitative analysis of polyhydroxyalkanoates (PHAs), biodegradable polyesters accumulated by various bacteria. This theme was exemplified for quantitative detection of the most common member of PHAs, poly(3-hydroxybutyrate) (PHB) in Cupriavidus Necator H16. We have identified the relevant spectral region (800–1800 cm−1) incorporating the Raman emission lines exploited for the calibration of PHB (PHB line at 1736 cm−1) and for the selection of the two internal standards (DNA at 786 cm−1 and Amide I at 1662 cm−1). In order to obtain quantitative data for calibration of intracellular content of PHB in bacterial cells reference samples containing PHB amounts—determined by gas chromatography—from 12% to 90% (w/w) were used. Consequently, analytical results based on this calibration can be used for fast and reliable determination of intracellular PHB content during biotechnological production of PHB since the whole procedure—from bacteria sampling, centrifugation, and sample preparation to Raman analysis—can take about 12 min. In contrast, gas chromatography analysis takes approximately 8 h.
Satoshi Nakamura - One of the best experts on this subject based on the ideXlab platform.
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evaluation of promoters for gene expression in polyhydroxyalkanoate producing Cupriavidus Necator h16
Applied Microbiology and Biotechnology, 2011Co-Authors: Toshiaki Fukui, Kei Ohsawa, Jun Mifune, Izumi Orita, Satoshi NakamuraAbstract:Five kinds of promoters were evaluated as tools for regulated gene expression in the PHA-producing bacterium Cupriavidus Necator. Several broad-host-range expression vectors were constructed by which expression of a reporter gene gfp was controlled by P lac , P tac , or P BAD derived from Escherichia coli, or promoter regions of phaC1 (P phaC ) or phaP1 (P phaP ) derived from C. Necator. Then, the gfp-expression profiles were determined in C. Necator strains harboring the constructed vectors when the cells were grown on fructose or soybean oil. P lac , P tac , P phaC , and P phaP mediated constitutive gene expression, among which P tac was the strongest promoter. lacI-P tac was not thoroughly functional even after addition of isopropyl-β-d-thiogalactopyranoside (IPTG), probably due to inability of C. Necator to uptake IPTG. Gene expression by araC-P BAD could be regulated by varying l-arabinose concentration in the medium, although P(3HB) production rate was slightly decreased in the recombinant. phaR-P phaP exhibited an expression profile tightly coupled with P(3HB) accumulation, suggesting application of the vector harboring phaR-P phaP for gene expression specific at the PHA-biosynthesis phase. The properties of these promoters were expected to be useful for effective engineering of PHA biosynthesis in C. Necator.
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microbial synthesis of poly r 3 hydroxybutyrate co 3 hydroxypropionate from unrelated carbon sources by engineered Cupriavidus Necator
Biomacromolecules, 2009Co-Authors: Toshiaki Fukui, Takeharu Tsuge, Mamie Suzuki, Satoshi NakamuraAbstract:Cupriavidus Necator was engineered aiming to synthesize poly[(R)-3-hydroxybutyrate-co-3-hydroxypropionate] copolyester, P(3HB-co-3HP), from structurally unrelated carbon sources without addition of any precursor compounds. We modified a metabolic pathway in C. Necator for generation of 3-hydroxypropionyl-CoA (3HP-CoA) by introducing malonyl-CoA reductase and the 3HP-CoA synthetase domain of trifunctional propionyl-CoA synthase; both members of the 3-hydroxypropionate cycle, a novel CO2-fixation pathway in the green nonsulfur bacterium Chloroflexus aurantiacus. In this recombinant strain, 3HP-CoA was expected to be provided from acetyl-CoA via malonyl-CoA, and then copolymerized by the function of polyhydroxyalkanoate synthase along with (R)-3-hydroxybutyryl-CoA synthesized from two acetyl-CoA molecules. C. Necator wild-type strains H16 and JMP134 harboring the two heterologous genes actually synthesized P(3HB-co-3HP) copolyester with 0.2−2.1 mol % of 3HP fraction from fructose or alkanoic acids of even ca...
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targeted engineering of Cupriavidus Necator chromosome for biosynthesis of poly 3 hydroxybutyrate co 3 hydroxyhexanoate from vegetable oil
Canadian Journal of Chemistry, 2008Co-Authors: Jun Mifune, Satoshi Nakamura, Toshiaki FukuiAbstract:Previous studies have demonstrated that heterologous expression of PHA synthase from Aeromonas caviae (PhaCAc), capable of accepting (R)-3-hydroxyacyl-CoA of C4–C7 as substrates, could confer the ability to PHA-negative mutant of Cupriavidus Necator PHB-4 to synthesize poly((R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate) [P(3HB-co-3HHx)] from vegetable oils. The mutation point within pha operon in PHB-4 was determined to be a single nonsense mutation within the PHA synthase gene (phaCCn), suggesting the much lower β-ketothiolase and NADPH-dependent acetoacetyl-CoA reductase activities observed in this strain would be a polar effect of the mutation. For further efficient biosynthesis of P(3HB-co-3HHx) copolyester, C. Necator wild strain H16 was engineered by homologous recombination targeting the chromosomal phaCCn, and the PHA productivity was compared with previous PHB–4-derived strain harboring phaCAc on a multi-copy plasmid (PHB–4/pJRDEE32d13). A strain H16CAc, in which phaCCn was substituted for phaC...
