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José Ruiz-herrera - One of the best experts on this subject based on the ideXlab platform.

  • A molecular probe for Basidiomycota: the Spermidine Synthase‐saccharopine dehydrogenase chimeric gene
    Fems Microbiology Letters, 2010
    Co-Authors: Claudia G. León-ramírez, Laura Valdés-santiago, Eduardo Campos-góngora, Lucila Ortiz-castellanos, Elva T. Aréchiga-carvajal, José Ruiz-herrera
    Abstract:

    By means of an in silico analysis, we demonstrated that a previously described chimeric gene (Spe-Sdh) encoding Spermidine Synthase, a key enzyme involved in the synthesis of polyamines, and saccharopine dehydrogenase, an enzyme involved in lysine synthesis in fungi, were present exclusively in members of all Basidiomycota subphyla, but not in any other group of living organisms. We used this feature to design degenerated primers to amplify a specific fragment of the Spe-Sdh gene by PCR, as a tool to unequivocally identify Basidiomycota isolates. The specificity of this procedure was tested using different fungal species. As expected, positive results were obtained only with Basidiomycota species, whereas no amplification was achieved with species belonging to other fungal phyla.

  • A molecular probe for Basidiomycota: the Spermidine Synthase-saccharopine dehydrogenase chimeric gene.
    FEMS microbiology letters, 2010
    Co-Authors: Claudia G. León-ramírez, Laura Valdés-santiago, Eduardo Campos-góngora, Lucila Ortiz-castellanos, Elva T. Aréchiga-carvajal, José Ruiz-herrera
    Abstract:

    By means of an in silico analysis, we demonstrated that a previously described chimeric gene (Spe-Sdh) encoding Spermidine Synthase, a key enzyme involved in the synthesis of polyamines, and saccharopine dehydrogenase, an enzyme involved in lysine synthesis in fungi, were present exclusively in members of all Basidiomycota subphyla, but not in any other group of living organisms. We used this feature to design degenerated primers to amplify a specific fragment of the Spe-Sdh gene by PCR, as a tool to unequivocally identify Basidiomycota isolates. The specificity of this procedure was tested using different fungal species. As expected, positive results were obtained only with Basidiomycota species, whereas no amplification was achieved with species belonging to other fungal phyla.

Juhani Jänne - One of the best experts on this subject based on the ideXlab platform.

Claudia G. León-ramírez - One of the best experts on this subject based on the ideXlab platform.

  • A molecular probe for Basidiomycota: the Spermidine Synthase‐saccharopine dehydrogenase chimeric gene
    Fems Microbiology Letters, 2010
    Co-Authors: Claudia G. León-ramírez, Laura Valdés-santiago, Eduardo Campos-góngora, Lucila Ortiz-castellanos, Elva T. Aréchiga-carvajal, José Ruiz-herrera
    Abstract:

    By means of an in silico analysis, we demonstrated that a previously described chimeric gene (Spe-Sdh) encoding Spermidine Synthase, a key enzyme involved in the synthesis of polyamines, and saccharopine dehydrogenase, an enzyme involved in lysine synthesis in fungi, were present exclusively in members of all Basidiomycota subphyla, but not in any other group of living organisms. We used this feature to design degenerated primers to amplify a specific fragment of the Spe-Sdh gene by PCR, as a tool to unequivocally identify Basidiomycota isolates. The specificity of this procedure was tested using different fungal species. As expected, positive results were obtained only with Basidiomycota species, whereas no amplification was achieved with species belonging to other fungal phyla.

  • A molecular probe for Basidiomycota: the Spermidine Synthase-saccharopine dehydrogenase chimeric gene.
    FEMS microbiology letters, 2010
    Co-Authors: Claudia G. León-ramírez, Laura Valdés-santiago, Eduardo Campos-góngora, Lucila Ortiz-castellanos, Elva T. Aréchiga-carvajal, José Ruiz-herrera
    Abstract:

    By means of an in silico analysis, we demonstrated that a previously described chimeric gene (Spe-Sdh) encoding Spermidine Synthase, a key enzyme involved in the synthesis of polyamines, and saccharopine dehydrogenase, an enzyme involved in lysine synthesis in fungi, were present exclusively in members of all Basidiomycota subphyla, but not in any other group of living organisms. We used this feature to design degenerated primers to amplify a specific fragment of the Spe-Sdh gene by PCR, as a tool to unequivocally identify Basidiomycota isolates. The specificity of this procedure was tested using different fungal species. As expected, positive results were obtained only with Basidiomycota species, whereas no amplification was achieved with species belonging to other fungal phyla.

Aran Incharoensakdi - One of the best experts on this subject based on the ideXlab platform.

  • Crystal structure of dimeric Synechococcus Spermidine Synthase with bound polyamine substrate and product
    The Biochemical journal, 2019
    Co-Authors: Gabriela Guédez, Apiradee Pothipongsa, Saowarath Jantaro, Aran Incharoensakdi, Saija Sirén, Arto Liljeblad, Tiina A. Salminen
    Abstract:

    Spermidine is a ubiquitous polyamine synthesized by Spermidine Synthase (SPDS) from the substrates, putrescine and decarboxylated S-adenosylmethionine (dcAdoMet). SPDS is generally active as homodimer, but higher oligomerization states have been reported in SPDS from thermophiles, which are less specific to putrescine as the aminoacceptor substrate. Several crystal structures of SPDS have been solved with and without bound substrates and/or products as well as inhibitors. Here, we determined the crystal structure of SPDS from the cyanobacterium Synechococcus (SySPDS) that is a homodimer, which we also observed in solution. Unlike crystal structures reported for bacterial and eukaryotic SPDS with bound ligands, SySPDS structure has not only bound putrescine substrate taken from the expression host, but also Spermidine product most probably as a result of an enzymatic reaction. Hence, to the best of our knowledge, this is the first structure reported with both amino ligands in the same structure. Interestingly, the gate-keeping loop is disordered in the putrescine-bound monomer while it is stabilized in the Spermidine-bound monomer of the SySPDS dimer. This confirms the gate-keeping loop as the key structural element that prepares the active site upon binding of dcAdoMet for the catalytic reaction of the amine donor and putrescine.

  • Molecular characterization and homology modeling of Spermidine Synthase from Synechococcus sp. PCC 7942.
    World journal of microbiology & biotechnology, 2017
    Co-Authors: Apiradee Pothipongsa, Saowarath Jantaro, Tiina A. Salminen, Aran Incharoensakdi
    Abstract:

    Spermidine Synthase (Spds) catalyzes the formation of Spermidine by transferring the aminopropyl group from decarboxylated S-adenosylmethionine (dcSAM) to putrescine. The Synechococcus spds gene encoding Spds was expressed in Escherichia coli. The purified recombinant enzyme had a molecular mass of 33 kDa and showed optimal activity at pH 7.5, 37 °C. The enzyme had higher affinity for dcSAM (Km, 20 µM) than for putrescine (Km, 111 µM) and was highly specific towards the diamine putrescine with no activity observed towards longer chain diamines. The three-dimensional structural model for Synechococcus Spds revealed that most of the ligand binding residues in Spds from Synechococcus sp. PCC 7942 are identical to those of human and parasite Spds. Based on the model, the highly conserved acidic residues, Asp89, Asp159 and Asp162, are involved in the binding of substrates putrescine and dcSAM and Pro166 seems to confer substrate specificity towards putrescine.

  • Spermidine Synthase is Required for Growth of Synechococcus sp. PCC 7942 Under Osmotic Stress.
    Current microbiology, 2016
    Co-Authors: Apiradee Pothipongsa, Saowarath Jantaro, Aran Incharoensakdi
    Abstract:

    The Synechococcus sp. PCC 7942 Spermidine Synthase encoded by spds gene (Synpcc7942_0628) is responsible for Spermidine biosynthesis. Two Synechococcus strains, the overexpressing spds (OX-spds) and the spds knockout (Δspds), were constructed and characterized for their growth and photosynthetic efficiency under osmotic stress imposed by sorbitol. The growth of Δspds was completely inhibited when cells were grown in the presence of 400 mM sorbitol. Under the same condition, the OX-spds showed a slightly higher growth than the wild type. The OX-spds under osmotic stress also had a significant increase of Spermidine level in conjunction with the up-regulation of the genes involved in Spermidine biosynthesis. A higher ratio of Spermidine to putrescine, an index for stress tolerance, under osmotic stress was found in the OX-spds strain than in the wild type. Overall results indicated that the Spermidine Synthase enzyme plays an essential role in the survival of Synechococcus sp. PCC 7942 under osmotic stress.

Apiradee Pothipongsa - One of the best experts on this subject based on the ideXlab platform.

  • Crystal structure of dimeric Synechococcus Spermidine Synthase with bound polyamine substrate and product
    The Biochemical journal, 2019
    Co-Authors: Gabriela Guédez, Apiradee Pothipongsa, Saowarath Jantaro, Aran Incharoensakdi, Saija Sirén, Arto Liljeblad, Tiina A. Salminen
    Abstract:

    Spermidine is a ubiquitous polyamine synthesized by Spermidine Synthase (SPDS) from the substrates, putrescine and decarboxylated S-adenosylmethionine (dcAdoMet). SPDS is generally active as homodimer, but higher oligomerization states have been reported in SPDS from thermophiles, which are less specific to putrescine as the aminoacceptor substrate. Several crystal structures of SPDS have been solved with and without bound substrates and/or products as well as inhibitors. Here, we determined the crystal structure of SPDS from the cyanobacterium Synechococcus (SySPDS) that is a homodimer, which we also observed in solution. Unlike crystal structures reported for bacterial and eukaryotic SPDS with bound ligands, SySPDS structure has not only bound putrescine substrate taken from the expression host, but also Spermidine product most probably as a result of an enzymatic reaction. Hence, to the best of our knowledge, this is the first structure reported with both amino ligands in the same structure. Interestingly, the gate-keeping loop is disordered in the putrescine-bound monomer while it is stabilized in the Spermidine-bound monomer of the SySPDS dimer. This confirms the gate-keeping loop as the key structural element that prepares the active site upon binding of dcAdoMet for the catalytic reaction of the amine donor and putrescine.

  • Molecular characterization and homology modeling of Spermidine Synthase from Synechococcus sp. PCC 7942.
    World journal of microbiology & biotechnology, 2017
    Co-Authors: Apiradee Pothipongsa, Saowarath Jantaro, Tiina A. Salminen, Aran Incharoensakdi
    Abstract:

    Spermidine Synthase (Spds) catalyzes the formation of Spermidine by transferring the aminopropyl group from decarboxylated S-adenosylmethionine (dcSAM) to putrescine. The Synechococcus spds gene encoding Spds was expressed in Escherichia coli. The purified recombinant enzyme had a molecular mass of 33 kDa and showed optimal activity at pH 7.5, 37 °C. The enzyme had higher affinity for dcSAM (Km, 20 µM) than for putrescine (Km, 111 µM) and was highly specific towards the diamine putrescine with no activity observed towards longer chain diamines. The three-dimensional structural model for Synechococcus Spds revealed that most of the ligand binding residues in Spds from Synechococcus sp. PCC 7942 are identical to those of human and parasite Spds. Based on the model, the highly conserved acidic residues, Asp89, Asp159 and Asp162, are involved in the binding of substrates putrescine and dcSAM and Pro166 seems to confer substrate specificity towards putrescine.

  • Spermidine Synthase is Required for Growth of Synechococcus sp. PCC 7942 Under Osmotic Stress.
    Current microbiology, 2016
    Co-Authors: Apiradee Pothipongsa, Saowarath Jantaro, Aran Incharoensakdi
    Abstract:

    The Synechococcus sp. PCC 7942 Spermidine Synthase encoded by spds gene (Synpcc7942_0628) is responsible for Spermidine biosynthesis. Two Synechococcus strains, the overexpressing spds (OX-spds) and the spds knockout (Δspds), were constructed and characterized for their growth and photosynthetic efficiency under osmotic stress imposed by sorbitol. The growth of Δspds was completely inhibited when cells were grown in the presence of 400 mM sorbitol. Under the same condition, the OX-spds showed a slightly higher growth than the wild type. The OX-spds under osmotic stress also had a significant increase of Spermidine level in conjunction with the up-regulation of the genes involved in Spermidine biosynthesis. A higher ratio of Spermidine to putrescine, an index for stress tolerance, under osmotic stress was found in the OX-spds strain than in the wild type. Overall results indicated that the Spermidine Synthase enzyme plays an essential role in the survival of Synechococcus sp. PCC 7942 under osmotic stress.