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David Eisenberg - One of the best experts on this subject based on the ideXlab platform.
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Crystal structure of the unactivated ribulose 1, 5-bisphosphate carboxylase/oxygenase complexed with a Transition State Analog, 2-carboxy-D-arabinitol 1, 5-bisphosphate
Protein science : a publication of the Protein Society, 1994Co-Authors: Kam Y. J. Zhang, Duilio Cascio, David EisenbergAbstract:The crystal structure of unactivated ribulose 1,5-bisphosphate carboxylase/oxygenase from Nicotiana tabacum complexed with a Transition State Analog, 2-carboxy-D-arabinitol 1,5-bisphosphate, was determined to 2.7 A resolution by X-ray crystallography. The Transition State Analog binds at the active site in an extended conformation. As compared to the binding of the same Analog in the activated enzyme, the Analog binds in a reverse orientation. The active site Lys 201 is within hydrogen bonding distance of the carboxyl oxygen of the Analog. Loop 6 (residues 330-339) remains open and flexible upon binding of the Analog in the unactivated enzyme, in contrast to the closed and ordered loop 6 in the activated enzyme complex. The Transition State Analog is exposed to solvent due to the open conformation of loop 6.
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crystal structure of the unactivated ribulose 1 5 bisphosphate carboxylase oxygenase complexed with a Transition State Analog 2 carboxy d arabinitol 1 5 bisphosphate
Protein Science, 1993Co-Authors: Kam Y. J. Zhang, Duilio Cascio, David EisenbergAbstract:The crystal structure of unactivated ribulose 1,5-bisphosphate carboxylase/oxygenase from Nicotiana tabacum complexed with a Transition State Analog, 2-carboxy-D-arabinitol 1,5-bisphosphate, was determined to 2.7 A resolution by X-ray crystallography. The Transition State Analog binds at the active site in an extended conformation. As compared to the binding of the same Analog in the activated enzyme, the Analog binds in a reverse orientation. The active site Lys 201 is within hydrogen bonding distance of the carboxyl oxygen of the Analog. Loop 6 (residues 330-339) remains open and flexible upon binding of the Analog in the unactivated enzyme, in contrast to the closed and ordered loop 6 in the activated enzyme complex. The Transition State Analog is exposed to solvent due to the open conformation of loop 6.
Kam Y. J. Zhang - One of the best experts on this subject based on the ideXlab platform.
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Crystal structure of the unactivated ribulose 1, 5-bisphosphate carboxylase/oxygenase complexed with a Transition State Analog, 2-carboxy-D-arabinitol 1, 5-bisphosphate
Protein science : a publication of the Protein Society, 1994Co-Authors: Kam Y. J. Zhang, Duilio Cascio, David EisenbergAbstract:The crystal structure of unactivated ribulose 1,5-bisphosphate carboxylase/oxygenase from Nicotiana tabacum complexed with a Transition State Analog, 2-carboxy-D-arabinitol 1,5-bisphosphate, was determined to 2.7 A resolution by X-ray crystallography. The Transition State Analog binds at the active site in an extended conformation. As compared to the binding of the same Analog in the activated enzyme, the Analog binds in a reverse orientation. The active site Lys 201 is within hydrogen bonding distance of the carboxyl oxygen of the Analog. Loop 6 (residues 330-339) remains open and flexible upon binding of the Analog in the unactivated enzyme, in contrast to the closed and ordered loop 6 in the activated enzyme complex. The Transition State Analog is exposed to solvent due to the open conformation of loop 6.
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crystal structure of the unactivated ribulose 1 5 bisphosphate carboxylase oxygenase complexed with a Transition State Analog 2 carboxy d arabinitol 1 5 bisphosphate
Protein Science, 1993Co-Authors: Kam Y. J. Zhang, Duilio Cascio, David EisenbergAbstract:The crystal structure of unactivated ribulose 1,5-bisphosphate carboxylase/oxygenase from Nicotiana tabacum complexed with a Transition State Analog, 2-carboxy-D-arabinitol 1,5-bisphosphate, was determined to 2.7 A resolution by X-ray crystallography. The Transition State Analog binds at the active site in an extended conformation. As compared to the binding of the same Analog in the activated enzyme, the Analog binds in a reverse orientation. The active site Lys 201 is within hydrogen bonding distance of the carboxyl oxygen of the Analog. Loop 6 (residues 330-339) remains open and flexible upon binding of the Analog in the unactivated enzyme, in contrast to the closed and ordered loop 6 in the activated enzyme complex. The Transition State Analog is exposed to solvent due to the open conformation of loop 6.
Duilio Cascio - One of the best experts on this subject based on the ideXlab platform.
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Crystal structure of the unactivated ribulose 1, 5-bisphosphate carboxylase/oxygenase complexed with a Transition State Analog, 2-carboxy-D-arabinitol 1, 5-bisphosphate
Protein science : a publication of the Protein Society, 1994Co-Authors: Kam Y. J. Zhang, Duilio Cascio, David EisenbergAbstract:The crystal structure of unactivated ribulose 1,5-bisphosphate carboxylase/oxygenase from Nicotiana tabacum complexed with a Transition State Analog, 2-carboxy-D-arabinitol 1,5-bisphosphate, was determined to 2.7 A resolution by X-ray crystallography. The Transition State Analog binds at the active site in an extended conformation. As compared to the binding of the same Analog in the activated enzyme, the Analog binds in a reverse orientation. The active site Lys 201 is within hydrogen bonding distance of the carboxyl oxygen of the Analog. Loop 6 (residues 330-339) remains open and flexible upon binding of the Analog in the unactivated enzyme, in contrast to the closed and ordered loop 6 in the activated enzyme complex. The Transition State Analog is exposed to solvent due to the open conformation of loop 6.
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crystal structure of the unactivated ribulose 1 5 bisphosphate carboxylase oxygenase complexed with a Transition State Analog 2 carboxy d arabinitol 1 5 bisphosphate
Protein Science, 1993Co-Authors: Kam Y. J. Zhang, Duilio Cascio, David EisenbergAbstract:The crystal structure of unactivated ribulose 1,5-bisphosphate carboxylase/oxygenase from Nicotiana tabacum complexed with a Transition State Analog, 2-carboxy-D-arabinitol 1,5-bisphosphate, was determined to 2.7 A resolution by X-ray crystallography. The Transition State Analog binds at the active site in an extended conformation. As compared to the binding of the same Analog in the activated enzyme, the Analog binds in a reverse orientation. The active site Lys 201 is within hydrogen bonding distance of the carboxyl oxygen of the Analog. Loop 6 (residues 330-339) remains open and flexible upon binding of the Analog in the unactivated enzyme, in contrast to the closed and ordered loop 6 in the activated enzyme complex. The Transition State Analog is exposed to solvent due to the open conformation of loop 6.
Chi-huey Wong - One of the best experts on this subject based on the ideXlab platform.
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Toward a Transition State Analog inhibitor of N-acetylglucosaminyl transferase V
Bioorganic & Medicinal Chemistry Letters, 1997Co-Authors: Mitsuaki Kaneko, Tetsuya Kajimoto, Osamu Kanie, Chi-huey WongAbstract:Abstract The tumor related enzyme N -acetylglucosaminyltransferase V catalyzes the transfer of GlcNAc to OH-6 of branching Man to give complex oligosaccharide structures. A Transition State Analog inhibitor of this enzyme was designed and a model compound was synthesized to illustrate the feasibility of the synthetic strategy.
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Cyclic Guanidino-Sugars with Low pKa as Transition-State Analog Inhibitors of Glycosidases: Neutral Instead of Charged Species Are the Active Forms
Journal of the American Chemical Society, 1996Co-Authors: Jin Hyun Jeong, Brion W. Murray, Shuichi Takayama, Chi-huey WongAbstract:Cyclic guanidino-sugars with different pKa values are designed and synthesized as Transition-State Analog inhibitors of galactosidases. Characterization of these structures (7, 10, 12) reveals that 7 and 10 are in a pH-dependent equilibrium between a furanose form and a mixture of neutral and protonated tetrahydropyrimidine forms. In contrast, the O-linked guanidino-sugar 12 exists as the tetrahydropyrimidine forms above pH 5. The furanose−tetrahydropyrimidine equilibrium can thus be modulated with the appropriate N-substituent which affects the guanidino-sugar pKa value. Enzymatic inhibition by 7, 10, and 12 is also pH-dependent, indicating that the enzymes recognize the tetrahydropyrimidine form. Evidence is presented to support a dominant role for the uncharged form of the six-membered cyclic guanidino-sugar in the inhibition of galactosidases. Though the inhibition potency is moderate (Ki range 4−50 μM), the use of cyclic guanidino-sugars in the study provides new insights into the mechanism of inhibi...
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Synthesis of iminothiasugar as a potential Transition-State Analog inhibitor of glycosyltransfer reactions
Tetrahedron Letters, 1994Co-Authors: Hideya Yuasa, Tetsuya Kajimoto, Chi-huey WongAbstract:Iminothiasugar 1, a potential Transition-State Analog inhibitor of glycosidases, was synthesized in 10 steps from D-xylose.
Enoch P. Baldwin - One of the best experts on this subject based on the ideXlab platform.
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Vanadate-based Transition-State Analog inhibitors of Cre–LoxP recombination
Biochemical and biophysical research communications, 2003Co-Authors: Shelley S. Martin, Shinichiro Wachi, Enoch P. BaldwinAbstract:Cre recombinase exchanges DNA strands at the LoxP recognition site via transphosphorylation reactions that involve pentacoordinate Transition States. We demonstrate that meta-vanadate ion (VO(3)(-)) and appropriate DNA substrates assemble a Transition-State Analog-like complex in the Cre active site. Meta-vanadate inhibits recombination of LoxP-derived oligonucleotide substrates that contain a gap at either or both scissile phosphates, but does not inhibit reactions with intact LoxP. The 3(')-hydroxyl group of the gapped substrate is required for inhibition, suggesting that vanadate is ligated by three oxo ligands. Assembly of the inhibited complex is slow (t(1/2)=19min at 4mM NaVO(3)) and requires Cre, substrates, and meta-vanadate. Holliday junction intermediates accumulated at lower meta-vanadate concentrations, suggesting that the second strand exchange is inhibited more readily than the first. The apparent K(D) for meta-vanadate is 1.5-2mM and binding shows positive cooperativity. This methodology may have general application for mechanistic studies of recombinase/topoisomerase-mediated strand exchange reactions.
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vanadate based Transition State Analog inhibitors of cre loxp recombination
Biochemical and Biophysical Research Communications, 2003Co-Authors: Shelley S. Martin, Shinichiro Wachi, Enoch P. BaldwinAbstract:Cre recombinase exchanges DNA strands at the LoxP recognition site via transphosphorylation reactions that involve pentacoordinate Transition States. We demonstrate that meta-vanadate ion (VO(3)(-)) and appropriate DNA substrates assemble a Transition-State Analog-like complex in the Cre active site. Meta-vanadate inhibits recombination of LoxP-derived oligonucleotide substrates that contain a gap at either or both scissile phosphates, but does not inhibit reactions with intact LoxP. The 3(')-hydroxyl group of the gapped substrate is required for inhibition, suggesting that vanadate is ligated by three oxo ligands. Assembly of the inhibited complex is slow (t(1/2)=19min at 4mM NaVO(3)) and requires Cre, substrates, and meta-vanadate. Holliday junction intermediates accumulated at lower meta-vanadate concentrations, suggesting that the second strand exchange is inhibited more readily than the first. The apparent K(D) for meta-vanadate is 1.5-2mM and binding shows positive cooperativity. This methodology may have general application for mechanistic studies of recombinase/topoisomerase-mediated strand exchange reactions.
