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Yoshimitsu Kakuta - One of the best experts on this subject based on the ideXlab platform.
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snapshot of a michaelis complex in a Sulfuryl transfer reaction crystal structure of a mouse sulfotransferase msult1d1 complexed with donor substrate and accepter substrate
Biochemical and Biophysical Research Communications, 2009Co-Authors: Takamasa Teramoto, Yoichi Sakakibara, Mingcheh Liu, Masahito Suiko, Makoto Kimura, Yoshimitsu KakutaAbstract:Abstract We report the crystal structure of mouse sulfotransferase, mSULT1D1, complexed with donor substrate 3′-phosphoadenosine 5′-phosphosulfate and accepter substrate p -nitrophenol. The structure is the first report of the native Michaelis complex of sulfotransferase. In the structure, three proposed catalytic residues (Lys48, Lys106, and His108) were in proper positions for engaging in the Sulfuryl transfer reaction. The data strongly support that the Sulfuryl transfer reaction proceeds through an S N 2-like in-line displacement mechanism.
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the Sulfuryl transfer mechanism crystal structure of a vanadate complex of estrogen sulfotransferase and mutational analysis
Journal of Biological Chemistry, 1998Co-Authors: Yoshimitsu Kakuta, Evgeny V Petrotchenko, Lars C Pedersen, Masahiko NegishiAbstract:Estrogen sulfotransferase (EST) catalyzes transfer of the 5'-Sulfuryl group of adenosine 3'-phosphate 5'-phosphosulfate (PAPS) to the 3alpha-phenol group of estrogenic steroids such as estradiol (E2). The recent crystal structure of EST-adenosine 3', 5'-diphosphate (PAP)- E2 complex has revealed that residues Lys48, Thr45, Thr51, Thr52, Lys106, His108, and Try240 are in position to play a catalytic role in the Sulfuryl transfer reaction of EST (Kakuta Y., Pedersen, L. G., Carter, C. W., Negishi, M., and Pedersen, L. C. (1997) Nat. Struct. Biol. 4, 904-908). Mutation of Lys48, Lys106, or His108 nearly abolishes EST activity, indicating that they play a critical role in catalysis. A present 2.2-A resolution structure of EST-PAP-vanadate complex indicates that the vanadate molecule adopts a trigonal bipyramidal geometry with its equatorial oxygens coordinated to these three residues. The apical positions of the vanadate molecule are occupied by a terminal oxygen of the 5'-phosphate of PAP (2.1 A) and a possible water molecule (2. 3 A). This water molecule superimposes well to the 3alpha-phenol group of E2 in the crystal structure of the EST.PAP.E2 complex. These structures are characteristic of the transition state for an in-line Sulfuryl transfer reaction from PAPS to E2. Moreover, residues Lys48, Lys106, and His108 are found to be coordinated with the vanadate molecule at the transition state of EST.
Mathias Schäfer - One of the best experts on this subject based on the ideXlab platform.
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synthesis and structural characterization of a new class of strong chiral bronsted acids 1 1 binaphthyl 2 2 bis Sulfuryl imides jingles
European Journal of Organic Chemistry, 2010Co-Authors: Albrecht Berkessel, Philipp Christ, Nicolas Leconte, Jörg‐m. Neudörfl, Mathias SchäferAbstract:We herein present the first synthesis of 1,1′-binaphthyl-2,2′-bis(Sulfuryl)imides (JINGLEs). This new class of chiral Bronsted acids was synthesized in one step from the corresponding BINOLs and imidobis(Sulfuryl chloride). A total of six enantiopure 1,1′-binaphthyl-2,2′-bis(Sulfuryl)imides, carrying different 3,3′-substituents, were synthesized and characterized, inter alia, by X-ray crystallography.
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Synthesis and Structural Characterization of a New Class of Strong Chiral Brønsted Acids: 1,1′‐Binaphthyl‐2,2′‐bis(Sulfuryl)imides (JINGLEs)
European Journal of Organic Chemistry, 2010Co-Authors: Albrecht Berkessel, Philipp Christ, Nicolas Leconte, Jörg‐m. Neudörfl, Mathias SchäferAbstract:We herein present the first synthesis of 1,1′-binaphthyl-2,2′-bis(Sulfuryl)imides (JINGLEs). This new class of chiral Bronsted acids was synthesized in one step from the corresponding BINOLs and imidobis(Sulfuryl chloride). A total of six enantiopure 1,1′-binaphthyl-2,2′-bis(Sulfuryl)imides, carrying different 3,3′-substituents, were synthesized and characterized, inter alia, by X-ray crystallography.
John Talarico - One of the best experts on this subject based on the ideXlab platform.
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Sulfuryl fluoride poisonings in structural fumigation a highly regulated industry potential causes and solutions
International Journal of Environmental Research and Public Health, 2019Co-Authors: Tracy Barreau, Sumi Hoshiko, Rick Kreutzer, Svetlana Smorodinsky, John TalaricoAbstract:Structural fumigations using Sulfuryl fluoride for the extermination of dry-wood termites are conducted by the thousands in California and other warm-weather states. Sulfuryl fluoride is an odorless gas that targets the nervous system and can cause respiratory irritation, pulmonary edema, nausea, vomiting, seizures, and death. Structural voids or compartments such as wall sockets, crawl spaces, cabinets, or cells in air mattresses may create ongoing exposure after a structure has been certified as safe. The authors describe a case of potential Sulfuryl fluoride exposure to a family following home fumigation. Despite regulation, Sulfuryl fluoride poisonings from structural fumigations continue to occur. This article examines the physical characteristics of Sulfuryl fluoride and the regulatory oversight of its application, in an effort to understand how and why these poisonings happen. Increasing aeration times of fumigated structures, overseeing monitoring efficacy, and using technology to capture clearance data could reduce Sulfuryl fluoride exposure and illness.
Alvan C. Hengge - One of the best experts on this subject based on the ideXlab platform.
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Transition state of the Sulfuryl transfer reaction of estrogen sulfotransferase.
The Journal of biological chemistry, 2006Co-Authors: Richard H. Hoff, Przemyslaw G. Czyryca, Meihao Sun, Thomas S. Leyh, Alvan C. HenggeAbstract:Abstract Kinetic isotope effects have been measured for the estrogen sulfotransferase-catalyzed Sulfuryl (SO3) transfer from p-nitrophenyl sulfate to the 5′-phosphoryl group of 3′-phosphoadenosine 5′-phosphate. 18(V/K)nonbridge = 1.0016 ± 0.0005, 18(V/K)bridge = 1.0280 ± 0.0006, and 15(V/K) = 1.0014 ± 0.0004. (15(V/K) refers to the nitro group in p-nitrophenyl sulfate). The kinetic isotope effects indicate substantial SO bond fission in the transition state, with partial charge neutralization of the leaving group. The small kinetic isotope effect in the nonbridging Sulfuryl oxygen atoms suggests no significant change in bond orders of these atoms occurs, consistent with modest nucleophilic involvement. A comparison of the data for enzymatic and uncatalyzed Sulfuryl transfer reactions suggests that both proceed through very similar transition states.
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Isotope effects in the study of phosphoryl and Sulfuryl transfer reactions.
Accounts of chemical research, 2002Co-Authors: Alvan C. HenggeAbstract:Phosphoryl and Sulfuryl transfer reactions are essential biological processes. Multiple kinetic isotope effects have provided significant insights into the transition states of these reactions. The data are reviewed for the uncatalyzed reactions of phosphate and sulfate monoesters and for a number of enzymatic phosphoryl transfer reactions. Uncatalyzed phosphoryl and Sulfuryl hydrolysis reactions are found to have very similar transition states. The phosphoryl transfer reaction catalyzed by protein-tyrosine phosphatases proceeds by a transition state very similar to that of the uncatalyzed reaction, but isotope effect data reveal an interesting interplay between the conserved arginine and enzyme dynamics involving general acid catalysis.
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Isotope effects and medium effects on Sulfuryl transfer reactions.
Journal of the American Chemical Society, 2001Co-Authors: Richard H. Hoff, Paul Larsen, Alvan C. HenggeAbstract:Kinetic isotope effects and medium effects have been measured for Sulfuryl-transfer reactions of the sulfate ester p-nitrophenyl sulfate (pNPS). The results are compared to those from previous studies of phosphoryl transfer, a reaction with mechanistic similarities. The N-15 and the bridge O-18 isotope effects for the reaction of the pNPS anion are very similar to those of the p-nitrophenyl phosphate (pNPP) dianion. This indicates that in the transition states for both reactions the leaving group bears nearly a full negative charge resulting from a large degree of bond cleavage to the leaving group. The nonbridge O-18 isotope effects support the notion that the Sulfuryl group resembles SO(3) in the transition state. The reaction of the neutral pNPS species in acid solution is mechanistically similar to the reaction of the pNPP monoanion. In both cases proton transfer from a nonbridge oxygen atom to the leaving group is largely complete in the transition state. Despite their mechanistic similarities, the phosphoryl- and Sulfuryl-transfer reactions differ markedly in their response to medium effects. Increasing proportions of the aprotic solvent DMSO to aqueous solutions of pNPP cause dramatic rate accelerations of up to 6 orders of magnitude, but only a 50-fold rate increase is observed for pNPS. Similarly, phosphoryl transfer from the pNPP dianion to tert-amyl alcohol is 9000-fold faster than the aqueous reaction, while the Sulfuryl transfer from the pNPS anion is some 40-fold slower. The enthalpic and entropic contributions to these differing medium effects have been measured and compared.
Albrecht Berkessel - One of the best experts on this subject based on the ideXlab platform.
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synthesis and structural characterization of a new class of strong chiral bronsted acids 1 1 binaphthyl 2 2 bis Sulfuryl imides jingles
European Journal of Organic Chemistry, 2010Co-Authors: Albrecht Berkessel, Philipp Christ, Nicolas Leconte, Jörg‐m. Neudörfl, Mathias SchäferAbstract:We herein present the first synthesis of 1,1′-binaphthyl-2,2′-bis(Sulfuryl)imides (JINGLEs). This new class of chiral Bronsted acids was synthesized in one step from the corresponding BINOLs and imidobis(Sulfuryl chloride). A total of six enantiopure 1,1′-binaphthyl-2,2′-bis(Sulfuryl)imides, carrying different 3,3′-substituents, were synthesized and characterized, inter alia, by X-ray crystallography.
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Synthesis and Structural Characterization of a New Class of Strong Chiral Brønsted Acids: 1,1′‐Binaphthyl‐2,2′‐bis(Sulfuryl)imides (JINGLEs)
European Journal of Organic Chemistry, 2010Co-Authors: Albrecht Berkessel, Philipp Christ, Nicolas Leconte, Jörg‐m. Neudörfl, Mathias SchäferAbstract:We herein present the first synthesis of 1,1′-binaphthyl-2,2′-bis(Sulfuryl)imides (JINGLEs). This new class of chiral Bronsted acids was synthesized in one step from the corresponding BINOLs and imidobis(Sulfuryl chloride). A total of six enantiopure 1,1′-binaphthyl-2,2′-bis(Sulfuryl)imides, carrying different 3,3′-substituents, were synthesized and characterized, inter alia, by X-ray crystallography.
