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Rodney Croteau - One of the best experts on this subject based on the ideXlab platform.

  • monoterpene synthases from common sage salvia officinalis cdna isolation characterization and functional expression of sabinene synthase 1 8 cineole synthase and bornyl diphosphate synthase
    Journal of Biological Chemistry, 1998
    Co-Authors: Mitchell L Wise, Thomas J Savage, Eva Katahira, Rodney Croteau
    Abstract:

    Abstract Common sage (Salvia officinalis) produces an extremely broad range of cyclic monoterpenes bearing diverse carbon skeletons, including members of thep-menthane (1,8-cineole), Pinane (α- and β-pinene), thujane (isothujone), camphane (camphene), and bornane (camphor) families. An homology-based polymerase chain reaction cloning strategy was developed and used to isolate the cDNAs encoding three multiproduct monoterpene synthases from this species that were functionally expressed in Escherichia coli. The heterologously expressed synthases produce (+)-bornyl diphosphate, 1,8-cineole, and (+)-sabinene, respectively, as their major products from geranyl diphosphate. The bornyl diphosphate synthase also produces significant amounts of (+)-α-pinene, (+)-camphene, and (±)-limonene. The 1,8-cineole synthase produces significant amounts of (+)- and (−)-α-pinene, (+)- and (−)-β-pinene, myrcene and (+)-sabinene, and the (+)-sabinene synthase produces significant quantities of γ-terpinene and terpinolene. All three enzymes appear to be translated as preproteins bearing an amino-terminal plastid targeting sequence, consistent with the plastidial origin of monoterpenes in plants. Deduced sequence analysis and size exclusion chromatography indicate that the recombinant bornyl diphosphate synthase is a homodimer, whereas the other two recombinant enzymes are monomeric, consistent with the size and subunit architecture of their native enzyme counterparts. The distribution and stereochemistry of the products generated by the recombinant (+)-bornyl diphosphate synthase suggest that this enzyme might represent both (+)-bornyl diphosphate synthase and (+)-pinene synthase which were previously assumed to be distinct enzymes.

  • Monoterpene Synthases from Common Sage (Salvia officinalis) cDNA ISOLATION, CHARACTERIZATION, AND FUNCTIONAL EXPRESSION OF (+)-SABINENE SYNTHASE, 1,8-CINEOLE SYNTHASE, AND (+)-BORNYL DIPHOSPHATE SYNTHASE
    Journal of Biological Chemistry, 1998
    Co-Authors: Mitchell L Wise, Thomas J Savage, Eva Katahira, Rodney Croteau
    Abstract:

    Abstract Common sage (Salvia officinalis) produces an extremely broad range of cyclic monoterpenes bearing diverse carbon skeletons, including members of thep-menthane (1,8-cineole), Pinane (α- and β-pinene), thujane (isothujone), camphane (camphene), and bornane (camphor) families. An homology-based polymerase chain reaction cloning strategy was developed and used to isolate the cDNAs encoding three multiproduct monoterpene synthases from this species that were functionally expressed in Escherichia coli. The heterologously expressed synthases produce (+)-bornyl diphosphate, 1,8-cineole, and (+)-sabinene, respectively, as their major products from geranyl diphosphate. The bornyl diphosphate synthase also produces significant amounts of (+)-α-pinene, (+)-camphene, and (±)-limonene. The 1,8-cineole synthase produces significant amounts of (+)- and (−)-α-pinene, (+)- and (−)-β-pinene, myrcene and (+)-sabinene, and the (+)-sabinene synthase produces significant quantities of γ-terpinene and terpinolene. All three enzymes appear to be translated as preproteins bearing an amino-terminal plastid targeting sequence, consistent with the plastidial origin of monoterpenes in plants. Deduced sequence analysis and size exclusion chromatography indicate that the recombinant bornyl diphosphate synthase is a homodimer, whereas the other two recombinant enzymes are monomeric, consistent with the size and subunit architecture of their native enzyme counterparts. The distribution and stereochemistry of the products generated by the recombinant (+)-bornyl diphosphate synthase suggest that this enzyme might represent both (+)-bornyl diphosphate synthase and (+)-pinene synthase which were previously assumed to be distinct enzymes.

Shijun Han - One of the best experts on this subject based on the ideXlab platform.

Mitchell L Wise - One of the best experts on this subject based on the ideXlab platform.

  • monoterpene synthases from common sage salvia officinalis cdna isolation characterization and functional expression of sabinene synthase 1 8 cineole synthase and bornyl diphosphate synthase
    Journal of Biological Chemistry, 1998
    Co-Authors: Mitchell L Wise, Thomas J Savage, Eva Katahira, Rodney Croteau
    Abstract:

    Abstract Common sage (Salvia officinalis) produces an extremely broad range of cyclic monoterpenes bearing diverse carbon skeletons, including members of thep-menthane (1,8-cineole), Pinane (α- and β-pinene), thujane (isothujone), camphane (camphene), and bornane (camphor) families. An homology-based polymerase chain reaction cloning strategy was developed and used to isolate the cDNAs encoding three multiproduct monoterpene synthases from this species that were functionally expressed in Escherichia coli. The heterologously expressed synthases produce (+)-bornyl diphosphate, 1,8-cineole, and (+)-sabinene, respectively, as their major products from geranyl diphosphate. The bornyl diphosphate synthase also produces significant amounts of (+)-α-pinene, (+)-camphene, and (±)-limonene. The 1,8-cineole synthase produces significant amounts of (+)- and (−)-α-pinene, (+)- and (−)-β-pinene, myrcene and (+)-sabinene, and the (+)-sabinene synthase produces significant quantities of γ-terpinene and terpinolene. All three enzymes appear to be translated as preproteins bearing an amino-terminal plastid targeting sequence, consistent with the plastidial origin of monoterpenes in plants. Deduced sequence analysis and size exclusion chromatography indicate that the recombinant bornyl diphosphate synthase is a homodimer, whereas the other two recombinant enzymes are monomeric, consistent with the size and subunit architecture of their native enzyme counterparts. The distribution and stereochemistry of the products generated by the recombinant (+)-bornyl diphosphate synthase suggest that this enzyme might represent both (+)-bornyl diphosphate synthase and (+)-pinene synthase which were previously assumed to be distinct enzymes.

  • Monoterpene Synthases from Common Sage (Salvia officinalis) cDNA ISOLATION, CHARACTERIZATION, AND FUNCTIONAL EXPRESSION OF (+)-SABINENE SYNTHASE, 1,8-CINEOLE SYNTHASE, AND (+)-BORNYL DIPHOSPHATE SYNTHASE
    Journal of Biological Chemistry, 1998
    Co-Authors: Mitchell L Wise, Thomas J Savage, Eva Katahira, Rodney Croteau
    Abstract:

    Abstract Common sage (Salvia officinalis) produces an extremely broad range of cyclic monoterpenes bearing diverse carbon skeletons, including members of thep-menthane (1,8-cineole), Pinane (α- and β-pinene), thujane (isothujone), camphane (camphene), and bornane (camphor) families. An homology-based polymerase chain reaction cloning strategy was developed and used to isolate the cDNAs encoding three multiproduct monoterpene synthases from this species that were functionally expressed in Escherichia coli. The heterologously expressed synthases produce (+)-bornyl diphosphate, 1,8-cineole, and (+)-sabinene, respectively, as their major products from geranyl diphosphate. The bornyl diphosphate synthase also produces significant amounts of (+)-α-pinene, (+)-camphene, and (±)-limonene. The 1,8-cineole synthase produces significant amounts of (+)- and (−)-α-pinene, (+)- and (−)-β-pinene, myrcene and (+)-sabinene, and the (+)-sabinene synthase produces significant quantities of γ-terpinene and terpinolene. All three enzymes appear to be translated as preproteins bearing an amino-terminal plastid targeting sequence, consistent with the plastidial origin of monoterpenes in plants. Deduced sequence analysis and size exclusion chromatography indicate that the recombinant bornyl diphosphate synthase is a homodimer, whereas the other two recombinant enzymes are monomeric, consistent with the size and subunit architecture of their native enzyme counterparts. The distribution and stereochemistry of the products generated by the recombinant (+)-bornyl diphosphate synthase suggest that this enzyme might represent both (+)-bornyl diphosphate synthase and (+)-pinene synthase which were previously assumed to be distinct enzymes.

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

Congxia Xie - One of the best experts on this subject based on the ideXlab platform.

  • Preparation of cis-Pinane via α-pinene hydrogenation in water by using Ru nanoparticles immobilized in functionalized amphiphilic mesoporous silica
    RSC Advances, 2017
    Co-Authors: Lihua Xie, Wang Xiaoyan, Yuan Bing, Congxia Xie
    Abstract:

    Amphiphilic mesoporous silica modified with trimethoxy (3,3,3-trifluoropropyl) silane (TFPS) and (3-aminopropyl) trimethoxysilane (APTS) was prepared by one-step synthesis. The structure and morphology of the mesoporous silica were characterized and confirmed by solid-state nuclear magnetic resonance, X-ray diffraction (XRD), N2 adsorption–desorption, Fourier transfer infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Meanwhile, the thermostability of the amphiphilic mesoporous silica was detected by thermogravimetric (TG) technique. Highly dispersed Ru nanoparticles supported on such amphiphilic mesoporous silica (marked as Ru/MF@MN) were synthesized by wet impregnation method with the assistance of ultrasonic. The catalyst was characterized by X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES). In water medium, Ru/MF@MN was used in α-pinene hydrogenation to prepare cis-Pinane. Under the optimum reaction conditions (35 °C, 2 MPa H2, 1 h, m (H2O) : m (α-pinene) : m (Ru/MF@MN) = 200 : 60 : 1), 99.9% α-pinene conversion and 98.9% cis-Pinane selectivity were obtained. When Ru/MF@MN was recycled six times, the conversion slightly decreased and the selectivity was nearly unchanged.

  • synthesis of magnetic ru fe3o4 c nanospheres with controlled carbon layer and its high selectivity to prepare cis Pinane
    Chemical Engineering Journal, 2016
    Co-Authors: Yue Liu, Congxia Xie, Shiwei Liu
    Abstract:

    Abstract A magnetic Ru/Fe3O4@C catalyst was prepared by loading Ru nanoparticles on a controller carbon layer. The characterization results showed that Ru/Fe3O4@C with the core-shell structured microspheres had good superparamagnetic properties and that the introduction of the controlled carbon layer adsorbent improved the morphological regularity, monodispersity and size uniformity of the Ru nanoparticles. The Ru/Fe3O4@C catalyst demonstrated a high catalytic activity towards the hydrogenation of α-pinene to form cis-Pinane. The conversion of α-pinene was 99.3% and the selectivity for cis-Pinane reached 98.2% at 160 °C for 2 h. The Ru/Fe3O4@C catalyst was easily separated from the reaction mixture when applying an external magnetic field, and the separated Ru/Fe3O4@C had a good reusability. After being reused 10 times, the α-pinene conversion and the cis-Pinane selectivity decreased to 97.6% and 97.1%, respectively.

  • synthesis of silanized magnetic ru fe3o4 sio2 nanospheres and their high selectivity to prepare cis Pinane
    RSC Advances, 2016
    Co-Authors: Yue Liu, Shiwei Liu, Congxia Xie
    Abstract:

    (3-Aminopropyl)-triethoxysilane (APTS) and (3-mercaptopropyl)-trimethoxysilane (MPTS) grafted SiO2-coated iron oxide (Fe3O4@SiO2) magnetic supports were prepared. Various noble metal nanoparticles such as Ru, Pt, Rh and Pd were directly grown on the surfaces of the magnetic supports with ultrasmall and nearly monodisperse sizes, especially the APTS grafted Fe3O4@SiO2 (Fe3O4@SiO2/APTS) nanospheres. The Fe3O4@SiO2/APTS/Ru catalyst demonstrated a high catalytic activity towards the hydrogenation of α-pinene to form cis-Pinane. The conversion of α-pinene was 99.1% and the selectivity for cis-Pinane reached 97.6% at 120 °C after 4 h. The Fe3O4@SiO2/APTS/Ru catalyst was easily separated from the reaction mixture when applying an external magnetic field, and the separated Fe3O4@SiO2/APTS/Ru had good reusability. After being reused eight times, the α-pinene conversion and the cis-Pinane selectivity also can reach 97.8% and 96.9%, respectively.

  • Synthesis of magnetic Ru/Fe3O4@C nanospheres with controlled carbon layer and its high selectivity to prepare cis-Pinane
    Chemical Engineering Journal, 2016
    Co-Authors: Liu Yue, Congxia Xie, Shiwei Liu
    Abstract:

    Abstract A magnetic Ru/Fe3O4@C catalyst was prepared by loading Ru nanoparticles on a controller carbon layer. The characterization results showed that Ru/Fe3O4@C with the core-shell structured microspheres had good superparamagnetic properties and that the introduction of the controlled carbon layer adsorbent improved the morphological regularity, monodispersity and size uniformity of the Ru nanoparticles. The Ru/Fe3O4@C catalyst demonstrated a high catalytic activity towards the hydrogenation of α-pinene to form cis-Pinane. The conversion of α-pinene was 99.3% and the selectivity for cis-Pinane reached 98.2% at 160 °C for 2 h. The Ru/Fe3O4@C catalyst was easily separated from the reaction mixture when applying an external magnetic field, and the separated Ru/Fe3O4@C had a good reusability. After being reused 10 times, the α-pinene conversion and the cis-Pinane selectivity decreased to 97.6% and 97.1%, respectively.

  • Synthesis of silanized magnetic Ru/Fe3O4@SiO2 nanospheres and their high selectivity to prepare cis-Pinane
    RSC Advances, 2016
    Co-Authors: Liu Yue, Shiwei Liu, Congxia Xie
    Abstract:

    (3-Aminopropyl)-triethoxysilane (APTS) and (3-mercaptopropyl)-trimethoxysilane (MPTS) grafted SiO2-coated iron oxide (Fe3O4@SiO2) magnetic supports were prepared. Various noble metal nanoparticles such as Ru, Pt, Rh and Pd were directly grown on the surfaces of the magnetic supports with ultrasmall and nearly monodisperse sizes, especially the APTS grafted Fe3O4@SiO2 (Fe3O4@SiO2/APTS) nanospheres. The Fe3O4@SiO2/APTS/Ru catalyst demonstrated a high catalytic activity towards the hydrogenation of α-pinene to form cis-Pinane. The conversion of α-pinene was 99.1% and the selectivity for cis-Pinane reached 97.6% at 120 °C after 4 h. The Fe3O4@SiO2/APTS/Ru catalyst was easily separated from the reaction mixture when applying an external magnetic field, and the separated Fe3O4@SiO2/APTS/Ru had good reusability. After being reused eight times, the α-pinene conversion and the cis-Pinane selectivity also can reach 97.8% and 96.9%, respectively.