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Colin Scott - One of the best experts on this subject based on the ideXlab platform.
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Crystal structure of a putrescine aminotransferase from Pseudomonas sp. strain AAC.
Acta crystallographica. Section F Structural biology communications, 2017Co-Authors: Matthew Wilding, Colin Scott, Janet Newman, Thomas S. PeatAbstract:The putrescine aminotransferase KES24511 from Pseudomonas sp. strain AAC was previously identified as an industrially relevant enzyme based on the discovery that it is able to promiscuously catalyse the transamination of 12-Aminododecanoic Acid. Here, the cloning, heterologous expression, purification and successful crystallization of the KES24511 protein are reported, which ultimately generated crystals adopting space group I2. The crystals diffracted X-rays to 2.07 Å resolution and data were collected using the microfocus beamline of the Australian Synchrotron. The structure was solved using molecular replacement, with a monomer from PDB entry 4a6t as the search model.
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Summary
2016Co-Authors: Pseudomonas Strain, Matthew Wilding, Ellen F. A. Walsh, Susan J, Colin ScottAbstract:A Pseudomonas species [Pseudomonas sp. strain amino alkanoate catabolism (AAC)] was identified that has the capacity to use 12-Aminododecanoic Acid, the constituent building block of homo-nylon-12, as a sole nitrogen source. Growth of Pseudomonas sp. strain AAC could also be sup-ported using a range of additional ω-amino alkanoates. This metabolic function was shown to be most probably dependent upon one or more transaminases (TAs). Fourteen genes encoding putative TAs were identified from the genome of Pseudomonas sp. AAC. Each of the 14 genes was cloned, 11 of which were successfully expressed in Escherichia coli and tested for activity against 12-Aminododecanoic Acid. In addition, physiological functions were proposed for 9 of the 14 TAs. Of the 14 proteins, activity was demonstrated in 9, and of note, 3 TAs were shown to be able to catalyse the transfer of the ω-amine from 12-Aminododecanoic Acid to pyruvate. Based on this study, three enzymes have been identified that are promising biocatalysts for the production of nylon and related polymers
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A β-Alanine Catabolism Pathway Containing a Highly Promiscuous ω-Transaminase in the 12-Aminododecanate-Degrading Pseudomonas Sp. Strain AAC
Applied and environmental microbiology, 2016Co-Authors: Matthew Wilding, Thomas S. Peat, Janet Newman, Colin ScottAbstract:We previously isolated the transaminase {"type":"entrez-protein","attrs":{"text":"KES23458","term_id":"664810528","term_text":"KES23458"}}KES23458 from Pseudomonas sp. strain AAC as a promising biocatalyst for the production of 12-Aminododecanoic Acid, a constituent building block of nylon-12. Here, we report the subsequent characterization of this transaminase. It exhibits activity with a broad substrate range which includes α-, β-, and ω-amino Acids, as well as α,ω-diamines and a number of other industrially relevant compounds. It is therefore a prospective candidate for the biosynthesis of a range of polyamide monomers. The crystal structure of {"type":"entrez-protein","attrs":{"text":"KES23458","term_id":"664810528","term_text":"KES23458"}}KES23458 revealed that the protein forms a dimer containing a large active site pocket and unusual phosphorylated histidine residues. To infer the physiological role of the transaminase, we expressed, purified, and characterized a dehydrogenase from the same operon, {"type":"entrez-protein","attrs":{"text":"KES23460","term_id":"664810530","term_text":"KES23460"}}KES23460. Unlike the transaminase, the dehydrogenase was shown to be quite selective, catalyzing the oxidation of malonic Acid semialdehyde, formed from β-alanine transamination via {"type":"entrez-protein","attrs":{"text":"KES23458","term_id":"664810528","term_text":"KES23458"}}KES23458. In keeping with previous reports, the dehydrogenase was shown to catalyze both a coenzyme A (CoA)-dependent reaction to form acetyl-CoA and a significantly slower CoA-independent reaction to form acetate. These findings support the original functional assignment of {"type":"entrez-protein","attrs":{"text":"KES23458","term_id":"664810528","term_text":"KES23458"}}KES23458 as a β-alanine transaminase. However, a seemingly well-adapted active site and promiscuity toward unnatural compounds, such as 12-Aminododecanoic Acid, suggest that this enzyme could perform multiple functions for Pseudomonas sp. strain AAC. IMPORTANCE We describe the characterization of an industrially relevant transaminase able to metabolize 12-Aminododecanoic Acid, a constituent building block of the widely used polymer nylon-12, and we report the biochemical and structural characterization of the transaminase protein. A physiological role for this highly promiscuous enzyme is proposed based on the characterization of a related gene from the host organism. Molecular dynamics simulations were carried out to compare the conformational changes in the transaminase protein to better understand the determinants of specificity in the protein. This study makes a substantial contribution that is of interest to the broad biotechnology and enzymology communities, providing insights into the catalytic activity of an industrially relevant biocatalyst as well as the biological function of this operon.
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Identification of novel transaminases from a 12-Aminododecanoic Acid-metabolizing Pseudomonas strain
Microbial biotechnology, 2015Co-Authors: Matthew Wilding, Ellen F. A. Walsh, Susan J. Dorrian, Colin ScottAbstract:A Pseudomonas species [Pseudomonas sp. strain amino alkanoate catabolism (AAC)] was identified that has the capacity to use 12-Aminododecanoic Acid, the constituent building block of homo-nylon-12, as a sole nitrogen source. Growth of Pseudomonas sp. strain AAC could also be supported using a range of additional ω-amino alkanoates. This metabolic function was shown to be most probably dependent upon one or more transaminases (TAs). Fourteen genes encoding putative TAs were identified from the genome of Pseudomonas sp. AAC. Each of the 14 genes was cloned, 11 of which were successfully expressed in Escherichia coli and tested for activity against 12-Aminododecanoic Acid. In addition, physiological functions were proposed for 9 of the 14 TAs. Of the 14 proteins, activity was demonstrated in 9, and of note, 3 TAs were shown to be able to catalyse the transfer of the ω-amine from 12-Aminododecanoic Acid to pyruvate. Based on this study, three enzymes have been identified that are promising biocatalysts for the production of nylon and related polymers.
Sasha Omanovic - One of the best experts on this subject based on the ideXlab platform.
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the effect of electrolyte flow on the performance of 12 aminododecanoic Acid as a carbon steel corrosion inhibitor in co2 saturated hydrochloric Acid
Corrosion Science, 2011Co-Authors: Saad Ghareba, Sasha OmanovicAbstract:Abstract The effect of flow and flow pattern of CO 2 -saturated HCl on the corrosion inhibition of carbon steel (CS) by 12-Aminododecanoic Acid (AA) was investigated in a square duct, rotating disk electrode (RDE), and jet impingement cell configuration. 3 mM AA provided high corrosion inhibition efficiency in the square duct and RDE configuration. However, in 1 mM AA the inhibition efficiency decreased with an increase in Re , due to desorption of AA from the CS surface. AA was found to poorly protect CS in the impingement-jet configuration at low Re , while at high Re , acceleration of CS corrosion was recorded.
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12 aminododecanoic Acid as a corrosion inhibitor for carbon steel
Electrochimica Acta, 2011Co-Authors: Saad Ghareba, Sasha OmanovicAbstract:Abstract The inhibiting effect of 12-Aminododecanoic Acid (AA) on corrosion of carbon steel (CS) was investigated in hydrochloric Acid of different pH, temperatures and over a prolonged period of time, and also in some other selected corrosive solutions. It was found that AA inhibits both partial corrosion reactions, with a slightly stronger inhibition of the anodic corrosion reaction. The corrosion protection mechanism is by formation of a surface-adsorbed AA monolayer that offers a hydrophobic barrier to transport of solvated corrosive ions to the surface. A maximum inhibition efficiency of 98.8 ± 0.5% was achieved in 0.5 M HCl. The adsorption of AA onto the CS surface was described by the Langmuir adsorption isotherm. The corresponding standard Gibbs energy of adsorption was calculated to be −26 kJ mol −1 . Polarization modulation infrared reflection absorption spectroscopy measurements revealed that the adsorbed AA monolayer is amorphous, which is due to the high heterogeneity of the CS surface.
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interaction of 12 aminododecanoic Acid with a carbon steel surface towards the development of green corrosion inhibitors
Corrosion Science, 2010Co-Authors: Saad Ghareba, Sasha OmanovicAbstract:Abstract The inhibiting effect of 12-Aminododecanoic Acid (AA) on corrosion of carbon steel (CS) in CO2-saturated hydrochloric Acid was investigated. It was found that AA acts as a mixed-type inhibitor, yielding a maximum inhibition efficiency of 98.1 ± 0.1%. The mechanism of its corrosion inhibition is by formation of a self-assembled monolayer (SAM), which presents a tight hydrophobic barrier imposed by the (–CH2)11 chain. In-situ PM-IRRAS measurements revealed that the SAM is amorphous. The SAM formation process was found to be spontaneous and reversible. The corresponding standard Gibbs energy of AA adsorption on CS was calculated to be −28 kJ mol−1.
Matthew Wilding - One of the best experts on this subject based on the ideXlab platform.
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Crystal structure of a putrescine aminotransferase from Pseudomonas sp. strain AAC.
Acta crystallographica. Section F Structural biology communications, 2017Co-Authors: Matthew Wilding, Colin Scott, Janet Newman, Thomas S. PeatAbstract:The putrescine aminotransferase KES24511 from Pseudomonas sp. strain AAC was previously identified as an industrially relevant enzyme based on the discovery that it is able to promiscuously catalyse the transamination of 12-Aminododecanoic Acid. Here, the cloning, heterologous expression, purification and successful crystallization of the KES24511 protein are reported, which ultimately generated crystals adopting space group I2. The crystals diffracted X-rays to 2.07 Å resolution and data were collected using the microfocus beamline of the Australian Synchrotron. The structure was solved using molecular replacement, with a monomer from PDB entry 4a6t as the search model.
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Summary
2016Co-Authors: Pseudomonas Strain, Matthew Wilding, Ellen F. A. Walsh, Susan J, Colin ScottAbstract:A Pseudomonas species [Pseudomonas sp. strain amino alkanoate catabolism (AAC)] was identified that has the capacity to use 12-Aminododecanoic Acid, the constituent building block of homo-nylon-12, as a sole nitrogen source. Growth of Pseudomonas sp. strain AAC could also be sup-ported using a range of additional ω-amino alkanoates. This metabolic function was shown to be most probably dependent upon one or more transaminases (TAs). Fourteen genes encoding putative TAs were identified from the genome of Pseudomonas sp. AAC. Each of the 14 genes was cloned, 11 of which were successfully expressed in Escherichia coli and tested for activity against 12-Aminododecanoic Acid. In addition, physiological functions were proposed for 9 of the 14 TAs. Of the 14 proteins, activity was demonstrated in 9, and of note, 3 TAs were shown to be able to catalyse the transfer of the ω-amine from 12-Aminododecanoic Acid to pyruvate. Based on this study, three enzymes have been identified that are promising biocatalysts for the production of nylon and related polymers
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A β-Alanine Catabolism Pathway Containing a Highly Promiscuous ω-Transaminase in the 12-Aminododecanate-Degrading Pseudomonas Sp. Strain AAC
Applied and environmental microbiology, 2016Co-Authors: Matthew Wilding, Thomas S. Peat, Janet Newman, Colin ScottAbstract:We previously isolated the transaminase {"type":"entrez-protein","attrs":{"text":"KES23458","term_id":"664810528","term_text":"KES23458"}}KES23458 from Pseudomonas sp. strain AAC as a promising biocatalyst for the production of 12-Aminododecanoic Acid, a constituent building block of nylon-12. Here, we report the subsequent characterization of this transaminase. It exhibits activity with a broad substrate range which includes α-, β-, and ω-amino Acids, as well as α,ω-diamines and a number of other industrially relevant compounds. It is therefore a prospective candidate for the biosynthesis of a range of polyamide monomers. The crystal structure of {"type":"entrez-protein","attrs":{"text":"KES23458","term_id":"664810528","term_text":"KES23458"}}KES23458 revealed that the protein forms a dimer containing a large active site pocket and unusual phosphorylated histidine residues. To infer the physiological role of the transaminase, we expressed, purified, and characterized a dehydrogenase from the same operon, {"type":"entrez-protein","attrs":{"text":"KES23460","term_id":"664810530","term_text":"KES23460"}}KES23460. Unlike the transaminase, the dehydrogenase was shown to be quite selective, catalyzing the oxidation of malonic Acid semialdehyde, formed from β-alanine transamination via {"type":"entrez-protein","attrs":{"text":"KES23458","term_id":"664810528","term_text":"KES23458"}}KES23458. In keeping with previous reports, the dehydrogenase was shown to catalyze both a coenzyme A (CoA)-dependent reaction to form acetyl-CoA and a significantly slower CoA-independent reaction to form acetate. These findings support the original functional assignment of {"type":"entrez-protein","attrs":{"text":"KES23458","term_id":"664810528","term_text":"KES23458"}}KES23458 as a β-alanine transaminase. However, a seemingly well-adapted active site and promiscuity toward unnatural compounds, such as 12-Aminododecanoic Acid, suggest that this enzyme could perform multiple functions for Pseudomonas sp. strain AAC. IMPORTANCE We describe the characterization of an industrially relevant transaminase able to metabolize 12-Aminododecanoic Acid, a constituent building block of the widely used polymer nylon-12, and we report the biochemical and structural characterization of the transaminase protein. A physiological role for this highly promiscuous enzyme is proposed based on the characterization of a related gene from the host organism. Molecular dynamics simulations were carried out to compare the conformational changes in the transaminase protein to better understand the determinants of specificity in the protein. This study makes a substantial contribution that is of interest to the broad biotechnology and enzymology communities, providing insights into the catalytic activity of an industrially relevant biocatalyst as well as the biological function of this operon.
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Identification of novel transaminases from a 12-Aminododecanoic Acid-metabolizing Pseudomonas strain
Microbial biotechnology, 2015Co-Authors: Matthew Wilding, Ellen F. A. Walsh, Susan J. Dorrian, Colin ScottAbstract:A Pseudomonas species [Pseudomonas sp. strain amino alkanoate catabolism (AAC)] was identified that has the capacity to use 12-Aminododecanoic Acid, the constituent building block of homo-nylon-12, as a sole nitrogen source. Growth of Pseudomonas sp. strain AAC could also be supported using a range of additional ω-amino alkanoates. This metabolic function was shown to be most probably dependent upon one or more transaminases (TAs). Fourteen genes encoding putative TAs were identified from the genome of Pseudomonas sp. AAC. Each of the 14 genes was cloned, 11 of which were successfully expressed in Escherichia coli and tested for activity against 12-Aminododecanoic Acid. In addition, physiological functions were proposed for 9 of the 14 TAs. Of the 14 proteins, activity was demonstrated in 9, and of note, 3 TAs were shown to be able to catalyse the transfer of the ω-amine from 12-Aminododecanoic Acid to pyruvate. Based on this study, three enzymes have been identified that are promising biocatalysts for the production of nylon and related polymers.
Jordi Puiggalí - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of poly(glycolic Acid‐alt‐12‐aminododecanoic Acid): The thermal polymerization kinetics of sodium N‐chloroacetyl‐12‐aminododecanoate
Journal of Polymer Science Part A: Polymer Chemistry, 2005Co-Authors: Emma Botines, Lourdes Franco, Xavier Ramis, Jordi PuiggalíAbstract:A new regular poly(ester amide) consisting of glycolic Acid and 12-Aminododecanoic Acid was synthesized by a thermal polycondensation method involving the formation of a metal halide salt. Polymerization could start in liquefied or solid phases, depending on the reaction temperature. The polymerization kinetics were investigated by isothermal and nonisothermal isoconversional methods. The reaction model was selected with both Coats–Redfern and isokinetic relationships. The activation energy was higher when the reaction took place mainly in the solid state. A compensation effect was found between the frequency factor and the activation energy. The thermal properties of the new polymer were studied as well as the isothermal crystallization from the melt state. Melt-grown spherulites were studied by means of polarizing optical microscopy. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1199–1213, 2006
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Synthesis and characterization of glycine copolymers of nylons 6 and 12
Journal of Polymer Science Part A: Polymer Chemistry, 1995Co-Authors: Lourdes Franco, Alexander Xenopoulos, Juan A. Subirana, Jordi PuiggalíAbstract:Copolymers of glycine and 6-aminohexanoic or 12-Aminododecanoic Acid within a range of molar compositions from 80/20 to 5/95 were prepared by solution polycondensation of the adequate proportion of the respective pentachlorophenyl ester hydrobromides. Despite their random composition, the copolymers obtained were found to be highly crystalline. Intrinsic viscosities of 2/6 and 2/12 copolyamides were similar and rather low (M n , ca. 3000-5000). Thermal post-polycondensation allowed to increase the molecular weight of 2/12 copolyamides, so that fibers could be prepared. The composition and sequence distributions were evaluated by means of 1 H- and 13 C-NMR spectroscopies. Copolyamides were also characterized in terms of thermal properties. Melting and glass transition temperatures are reported. Crystallinity was evaluated from heats of fusion. Crystalline structure was examined by infrared spectroscopy and wide-angle x-ray diffraction. The presence of structures related to the polyglycine 1 and to α/γ-nylons was confirmed depending on the molar composition. Highly oriented fibers with good tensile properties were obtained from the nylon 2/12 (10:90) copolymer
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Synthesis and Characterization of the Two Crystal Forms of Nylon 2/12
Macromolecules, 1994Co-Authors: M. Bermudez, Jordi Puiggalí, S. Munoz-guerraAbstract:The alternating copolyamide poly(glycyl-12-Aminododecanoic Acid) (nylon 2/12), was prepared by polycondensation of the «dimer» glycyl-12-Aminododecanoic Acid pentachlorophenyl ester and subsequently studied by calorimetry, X-ray diffraction, and electron microscopy. Two crystal forms reminiscent of those characteristic of polypeptides and nylons, respectively, were found for nylon 2/12. Form I is made of fully extended chains arranged in hydrogen-bonded sheed which are staggered in a layered structure similar to the α-form of nylons. Form II consists of a hexagonal array of 6-fold helices intermolecularly linked in a crystal lattice of a=0.419 nm and c=1.88 nm with features close to the peculiar polyglycine II crystal form
Saad Ghareba - One of the best experts on this subject based on the ideXlab platform.
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the effect of electrolyte flow on the performance of 12 aminododecanoic Acid as a carbon steel corrosion inhibitor in co2 saturated hydrochloric Acid
Corrosion Science, 2011Co-Authors: Saad Ghareba, Sasha OmanovicAbstract:Abstract The effect of flow and flow pattern of CO 2 -saturated HCl on the corrosion inhibition of carbon steel (CS) by 12-Aminododecanoic Acid (AA) was investigated in a square duct, rotating disk electrode (RDE), and jet impingement cell configuration. 3 mM AA provided high corrosion inhibition efficiency in the square duct and RDE configuration. However, in 1 mM AA the inhibition efficiency decreased with an increase in Re , due to desorption of AA from the CS surface. AA was found to poorly protect CS in the impingement-jet configuration at low Re , while at high Re , acceleration of CS corrosion was recorded.
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12 aminododecanoic Acid as a corrosion inhibitor for carbon steel
Electrochimica Acta, 2011Co-Authors: Saad Ghareba, Sasha OmanovicAbstract:Abstract The inhibiting effect of 12-Aminododecanoic Acid (AA) on corrosion of carbon steel (CS) was investigated in hydrochloric Acid of different pH, temperatures and over a prolonged period of time, and also in some other selected corrosive solutions. It was found that AA inhibits both partial corrosion reactions, with a slightly stronger inhibition of the anodic corrosion reaction. The corrosion protection mechanism is by formation of a surface-adsorbed AA monolayer that offers a hydrophobic barrier to transport of solvated corrosive ions to the surface. A maximum inhibition efficiency of 98.8 ± 0.5% was achieved in 0.5 M HCl. The adsorption of AA onto the CS surface was described by the Langmuir adsorption isotherm. The corresponding standard Gibbs energy of adsorption was calculated to be −26 kJ mol −1 . Polarization modulation infrared reflection absorption spectroscopy measurements revealed that the adsorbed AA monolayer is amorphous, which is due to the high heterogeneity of the CS surface.
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interaction of 12 aminododecanoic Acid with a carbon steel surface towards the development of green corrosion inhibitors
Corrosion Science, 2010Co-Authors: Saad Ghareba, Sasha OmanovicAbstract:Abstract The inhibiting effect of 12-Aminododecanoic Acid (AA) on corrosion of carbon steel (CS) in CO2-saturated hydrochloric Acid was investigated. It was found that AA acts as a mixed-type inhibitor, yielding a maximum inhibition efficiency of 98.1 ± 0.1%. The mechanism of its corrosion inhibition is by formation of a self-assembled monolayer (SAM), which presents a tight hydrophobic barrier imposed by the (–CH2)11 chain. In-situ PM-IRRAS measurements revealed that the SAM is amorphous. The SAM formation process was found to be spontaneous and reversible. The corresponding standard Gibbs energy of AA adsorption on CS was calculated to be −28 kJ mol−1.
