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Jie Cheng - One of the best experts on this subject based on the ideXlab platform.

  • production of nonnatural straight Chain amino acid 6 aminocaproate via an artificial iterative carbon Chain Extension cycle
    Metabolic Engineering, 2019
    Co-Authors: Jie Cheng, Michael P Torrensspence, Xiaohua Zhou, Dan Wang, Jingke Weng, Qinhong Wang
    Abstract:

    Abstract Bioplastics produced from microbial source are promising green alternatives to traditional petrochemical-derived plastics. Nonnatural straight-Chain amino acids, especially 5-aminovalerate, 6-aminocaproate and 7-aminoheptanoate are potential monomers for the synthesis of polymeric bioplastics as their primary amine and carboxylic acid are ideal functional groups for polymerization. Previous pathways for 5-aminovalerate and 6-aminocaproate biosynthesis in microorganisms are derived from L-lysine catabolism and the citric acid cycle, respectively. Here, we show the construction of an artificial iterative carbon-Chain-Extension cycle in Escherichia coli for simultaneous production of a series of nonnatural amino acids with varying Chain length. Overexpression of L-lysine α-oxidase in E. coli yields 2-keto-6-aminocaproate (2K6AC) as a non-native substrate for the artificial iterative carbon-Chain-Extension cycle. The Chain-extended α-ketoacid products are decarboxylated and oxidized by an α-ketoacid decarboxylase and an aldehyde dehydrogenase, respectively, to yield their corresponding nonnatural straight-Chain amino acids. The engineered system demonstrated simultaneous in vitro production of 99.16 mg/L of 5-aminovalerate, 46.96 mg/L of 6-aminocaproate and 4.78 mg/L of 7-aminoheptanoate after 8 h of enzyme catalysis starting from 2K6AC as the substrate. Furthermore, simultaneous production of 2.15 g/L of 5-aminovalerate, 24.12 mg/L of 6-aminocaproate and 4.74 mg/L of 7-aminoheptanoate was achieved in engineered E. coli. This work illustrates a promising metabolic-engineering strategy to access other medium-Chain organic acids with –NH2, –SCH3, –SOCH3, –SH, –COOH, –COH, or –OH functional groups through carbon-Chain-elongation chemistry.

  • production of nonnatural straight Chain amino acid 6 aminocaproate via an artificial iterative carbon Chain Extension cycle
    bioRxiv, 2019
    Co-Authors: Jie Cheng, Michael P Torrensspence, Xiaohua Zhou, Dan Wang, Jingke Weng, Tingting Song, Huayu Wang, Qinhong Wang
    Abstract:

    Abstract Bioplastics produced from microbial source are promising green alternatives to traditional petrochemical-derived plastics. Nonnatural straight-Chain amino acids, especially 5-aminovalerate, 6-aminocaproate and 7-aminoheptanoate are potential monomers for the synthesis of polymeric bioplastics as their primary amine and carboxylic acid are ideal functional groups for polymerization. Previous pathways for 5-aminovalerate and 6-aminocaproate biosynthesis in microorganisms are derived from L-lysine catabolism and citric acid cycle, respectively. Here, we show the construction of an artificial iterative carbon-Chain-Extension cycle in Escherichia coli for simultaneous production of a series of nonnatural amino acids with varying Chain length. Overexpression of L-lysine α-oxidase in E. coli yields 2-keto-6-aminocaproate as a non-native substrate for the artificial iterative carbon-Chain-Extension cycle. The Chain-extended α-ketoacid is subsequently decarboxylated and oxidized by an α-ketoacid decarboxylase and an aldehyde dehydrogenase, respectively, to yield the nonnatural straight-Chain amino acid products. The engineered system demonstrated simultaneous in vitro production of 99.16 mg/L of 5-aminovalerate, 46.96 mg/L of 6-aminocaproate and 4.78 mg/L of 7-aminoheptanoate after 8 hours of enzyme catalysis starting from 2-keto-6-aminocaproate as the substrate. Furthermore, simultaneous production of 2.15 g/L of 5-aminovalerate, 24.12 mg/L of 6-aminocaproate and 4.74 mg/L of 7-aminoheptanoate was achieved in engineered E. coli. This work illustrates a promising metabolic-engineering strategy to access other medium-Chain organic acids with -NH2,-SCH3, -SOCH3, -SH, -COOH, -COH, or -OH functional groups through carbon-Chain-elongation chemistry.

Qinhong Wang - One of the best experts on this subject based on the ideXlab platform.

  • production of nonnatural straight Chain amino acid 6 aminocaproate via an artificial iterative carbon Chain Extension cycle
    Metabolic Engineering, 2019
    Co-Authors: Jie Cheng, Michael P Torrensspence, Xiaohua Zhou, Dan Wang, Jingke Weng, Qinhong Wang
    Abstract:

    Abstract Bioplastics produced from microbial source are promising green alternatives to traditional petrochemical-derived plastics. Nonnatural straight-Chain amino acids, especially 5-aminovalerate, 6-aminocaproate and 7-aminoheptanoate are potential monomers for the synthesis of polymeric bioplastics as their primary amine and carboxylic acid are ideal functional groups for polymerization. Previous pathways for 5-aminovalerate and 6-aminocaproate biosynthesis in microorganisms are derived from L-lysine catabolism and the citric acid cycle, respectively. Here, we show the construction of an artificial iterative carbon-Chain-Extension cycle in Escherichia coli for simultaneous production of a series of nonnatural amino acids with varying Chain length. Overexpression of L-lysine α-oxidase in E. coli yields 2-keto-6-aminocaproate (2K6AC) as a non-native substrate for the artificial iterative carbon-Chain-Extension cycle. The Chain-extended α-ketoacid products are decarboxylated and oxidized by an α-ketoacid decarboxylase and an aldehyde dehydrogenase, respectively, to yield their corresponding nonnatural straight-Chain amino acids. The engineered system demonstrated simultaneous in vitro production of 99.16 mg/L of 5-aminovalerate, 46.96 mg/L of 6-aminocaproate and 4.78 mg/L of 7-aminoheptanoate after 8 h of enzyme catalysis starting from 2K6AC as the substrate. Furthermore, simultaneous production of 2.15 g/L of 5-aminovalerate, 24.12 mg/L of 6-aminocaproate and 4.74 mg/L of 7-aminoheptanoate was achieved in engineered E. coli. This work illustrates a promising metabolic-engineering strategy to access other medium-Chain organic acids with –NH2, –SCH3, –SOCH3, –SH, –COOH, –COH, or –OH functional groups through carbon-Chain-elongation chemistry.

  • production of nonnatural straight Chain amino acid 6 aminocaproate via an artificial iterative carbon Chain Extension cycle
    bioRxiv, 2019
    Co-Authors: Jie Cheng, Michael P Torrensspence, Xiaohua Zhou, Dan Wang, Jingke Weng, Tingting Song, Huayu Wang, Qinhong Wang
    Abstract:

    Abstract Bioplastics produced from microbial source are promising green alternatives to traditional petrochemical-derived plastics. Nonnatural straight-Chain amino acids, especially 5-aminovalerate, 6-aminocaproate and 7-aminoheptanoate are potential monomers for the synthesis of polymeric bioplastics as their primary amine and carboxylic acid are ideal functional groups for polymerization. Previous pathways for 5-aminovalerate and 6-aminocaproate biosynthesis in microorganisms are derived from L-lysine catabolism and citric acid cycle, respectively. Here, we show the construction of an artificial iterative carbon-Chain-Extension cycle in Escherichia coli for simultaneous production of a series of nonnatural amino acids with varying Chain length. Overexpression of L-lysine α-oxidase in E. coli yields 2-keto-6-aminocaproate as a non-native substrate for the artificial iterative carbon-Chain-Extension cycle. The Chain-extended α-ketoacid is subsequently decarboxylated and oxidized by an α-ketoacid decarboxylase and an aldehyde dehydrogenase, respectively, to yield the nonnatural straight-Chain amino acid products. The engineered system demonstrated simultaneous in vitro production of 99.16 mg/L of 5-aminovalerate, 46.96 mg/L of 6-aminocaproate and 4.78 mg/L of 7-aminoheptanoate after 8 hours of enzyme catalysis starting from 2-keto-6-aminocaproate as the substrate. Furthermore, simultaneous production of 2.15 g/L of 5-aminovalerate, 24.12 mg/L of 6-aminocaproate and 4.74 mg/L of 7-aminoheptanoate was achieved in engineered E. coli. This work illustrates a promising metabolic-engineering strategy to access other medium-Chain organic acids with -NH2,-SCH3, -SOCH3, -SH, -COOH, -COH, or -OH functional groups through carbon-Chain-elongation chemistry.

Martina H Stenzel - One of the best experts on this subject based on the ideXlab platform.

  • shell cross linked vesicles synthesized from block copolymers of poly d l lactide and poly n isopropyl acrylamide as thermoresponsive nanocontainers
    Langmuir, 2004
    Co-Authors: Michelle Hales, Thomas P Davis, Christopher Barnerkowollik, Martina H Stenzel
    Abstract:

    A polylactide (D,L-PLA) macroRAFT agent was prepared by utilizing a hydroxyl-functional trithiocarbonate as a coinitiator for the ring-opening polymerization. The length of the resultant polymer was controlled by the concentration of the coinitiator leading to the formation of two PLA polymers with M(n) = 12500 g mol(-)(1) (PDI = 1.46) and M(n) = 20500 g mol(-)(1) (PDI = 1.38) each with omega-trithiocarbonate functionality. Chain Extension of PLA via the RAFT (free radical) polymerization of N-isopropyl acrylamide (NIPAAm) resulted in the formation of amphiphilic block copolymers with the PNIPAAm block increasing in size with conversion. TEM measurements of the aggregates obtained by self-organization of the block copolymers in aqueous solutions indicated the formation of vesicles. The sizes of these aggregates were influenced by the ratio of both blocks and the molecular weight of each block. The lower critical solution temperature (LCST) of the block copolymer was largely unaffected by the size of each block. UV turbidity measurements indicated a higher LCST for the block copolymers than for the corresponding PNIPAAm homopolymers. Stabilization of the vesicles was attained by a cross-linking Chain Extension of the PNIPAAm block using hexamethylene diacrylate. As the trithiocarbonate group was located between the PLA and PNIPAAm blocks, the Chain Extension resulted in a cross-linked layer between the core and corona of the vesicles.

  • Shell-cross-linked vesicles synthesized from block copolymers of poly(D,L-lactide) and poly(N-isopropyl acrylamide) as thermoresponsive nanocontainers
    Langmuir, 2004
    Co-Authors: Michelle Hales, Thomas P Davis, Christopher Barner-kowollik, Martina H Stenzel
    Abstract:

    A polylactide (D,L-PLA) macroRAFT agent was prepared by utilizing a hydroxyl-functional trithiocarbonate as a coinitiator for the ring-opening polymerization. The length of the resultant polymer was controlled by the concentration of the coinitiator leading to the formation of two PLA polymers with Mn = 12500 g mol-1 (PDI = 1.46) and Mn = 20500 g mol-1 (PDI = 1.38) each with ω-trithiocarbonate functionality. Chain Extension of PLA via the RAFT (free radical) polymerization of N-isopropyl acrylamide (NIPAAm) resulted in the formation of amphiphilic block copolymers with the PNIPAAm block increasing in size with conversion. TEM measurements of the aggregates obtained by self-organization of the block copolymers in aqueous solutions indicated the formation of vesicles. The sizes of these aggregates were influenced by the ratio of both blocks and the molecular weight of each block. The lower critical solution temperature (LCST) of the block copolymer was largely unaffected by the size of each block. UV turbidity measurements indicated a higher LCST for the block copolymers than for the corresponding PNIPAAm homopolymers. Stabilization of the vesicles was attained by a cross-linking Chain Extension of the PNIPAAm block using hexamethylene diacrylate. As the trithiocarbonate group was located between the PLA and PNIPAAm blocks, the Chain Extension resulted in a cross-linked layer between the core and corona of the vesicles.

Sebastien Perrier - One of the best experts on this subject based on the ideXlab platform.

  • synthesis of sequence controlled multiblock single Chain nanoparticles by a stepwise folding Chain Extension folding process
    Macromolecules, 2016
    Co-Authors: Junliang Zhang, Guillaume Gody, Matthias Hartlieb, Sylvain Catrouillet, Jonathan Moffat, Sebastien Perrier
    Abstract:

    The specific activity of proteins can be traced back to their highly defined tertiary structure, which is a result of a perfectly controlled intraChain folding process. In the herein presented work the folding of different distinct domains within a single macromolecule is demonstrated. RAFT polymerization was used to produce multiblock copolymers, which are decorated with pendant hydroxyl groups in foldable sections, separated by nonfunctional spacer blocks in between. OH-bearing blocks were folded using an isocyanate cross-linker prior to Chain Extension to form single Chain nanoparticles (SCNP). After addition of a spacer block and a further OH decorated block, folding was repeated to generate individual SCNP within a polymer Chain. Control experiments were performed indicating the absence of interblock cross-linking. SCNP were found to be condensed by a combination of covalent and supramolecular (hydrogen bonds) linkage. The approach was used to create a highly complex pentablock copolymer having three...

Jingke Weng - One of the best experts on this subject based on the ideXlab platform.

  • production of nonnatural straight Chain amino acid 6 aminocaproate via an artificial iterative carbon Chain Extension cycle
    Metabolic Engineering, 2019
    Co-Authors: Jie Cheng, Michael P Torrensspence, Xiaohua Zhou, Dan Wang, Jingke Weng, Qinhong Wang
    Abstract:

    Abstract Bioplastics produced from microbial source are promising green alternatives to traditional petrochemical-derived plastics. Nonnatural straight-Chain amino acids, especially 5-aminovalerate, 6-aminocaproate and 7-aminoheptanoate are potential monomers for the synthesis of polymeric bioplastics as their primary amine and carboxylic acid are ideal functional groups for polymerization. Previous pathways for 5-aminovalerate and 6-aminocaproate biosynthesis in microorganisms are derived from L-lysine catabolism and the citric acid cycle, respectively. Here, we show the construction of an artificial iterative carbon-Chain-Extension cycle in Escherichia coli for simultaneous production of a series of nonnatural amino acids with varying Chain length. Overexpression of L-lysine α-oxidase in E. coli yields 2-keto-6-aminocaproate (2K6AC) as a non-native substrate for the artificial iterative carbon-Chain-Extension cycle. The Chain-extended α-ketoacid products are decarboxylated and oxidized by an α-ketoacid decarboxylase and an aldehyde dehydrogenase, respectively, to yield their corresponding nonnatural straight-Chain amino acids. The engineered system demonstrated simultaneous in vitro production of 99.16 mg/L of 5-aminovalerate, 46.96 mg/L of 6-aminocaproate and 4.78 mg/L of 7-aminoheptanoate after 8 h of enzyme catalysis starting from 2K6AC as the substrate. Furthermore, simultaneous production of 2.15 g/L of 5-aminovalerate, 24.12 mg/L of 6-aminocaproate and 4.74 mg/L of 7-aminoheptanoate was achieved in engineered E. coli. This work illustrates a promising metabolic-engineering strategy to access other medium-Chain organic acids with –NH2, –SCH3, –SOCH3, –SH, –COOH, –COH, or –OH functional groups through carbon-Chain-elongation chemistry.

  • production of nonnatural straight Chain amino acid 6 aminocaproate via an artificial iterative carbon Chain Extension cycle
    bioRxiv, 2019
    Co-Authors: Jie Cheng, Michael P Torrensspence, Xiaohua Zhou, Dan Wang, Jingke Weng, Tingting Song, Huayu Wang, Qinhong Wang
    Abstract:

    Abstract Bioplastics produced from microbial source are promising green alternatives to traditional petrochemical-derived plastics. Nonnatural straight-Chain amino acids, especially 5-aminovalerate, 6-aminocaproate and 7-aminoheptanoate are potential monomers for the synthesis of polymeric bioplastics as their primary amine and carboxylic acid are ideal functional groups for polymerization. Previous pathways for 5-aminovalerate and 6-aminocaproate biosynthesis in microorganisms are derived from L-lysine catabolism and citric acid cycle, respectively. Here, we show the construction of an artificial iterative carbon-Chain-Extension cycle in Escherichia coli for simultaneous production of a series of nonnatural amino acids with varying Chain length. Overexpression of L-lysine α-oxidase in E. coli yields 2-keto-6-aminocaproate as a non-native substrate for the artificial iterative carbon-Chain-Extension cycle. The Chain-extended α-ketoacid is subsequently decarboxylated and oxidized by an α-ketoacid decarboxylase and an aldehyde dehydrogenase, respectively, to yield the nonnatural straight-Chain amino acid products. The engineered system demonstrated simultaneous in vitro production of 99.16 mg/L of 5-aminovalerate, 46.96 mg/L of 6-aminocaproate and 4.78 mg/L of 7-aminoheptanoate after 8 hours of enzyme catalysis starting from 2-keto-6-aminocaproate as the substrate. Furthermore, simultaneous production of 2.15 g/L of 5-aminovalerate, 24.12 mg/L of 6-aminocaproate and 4.74 mg/L of 7-aminoheptanoate was achieved in engineered E. coli. This work illustrates a promising metabolic-engineering strategy to access other medium-Chain organic acids with -NH2,-SCH3, -SOCH3, -SH, -COOH, -COH, or -OH functional groups through carbon-Chain-elongation chemistry.