The Experts below are selected from a list of 15414 Experts worldwide ranked by ideXlab platform
Carolyn R. Bertozzi - One of the best experts on this subject based on the ideXlab platform.
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A small-molecule switch for Golgi Sulfotransferases
Proceedings of the National Academy of Sciences of the United States of America, 2004Co-Authors: Christopher L. De Graffenried, Scott T. Laughlin, Jennifer J. Kohler, Carolyn R. BertozziAbstract:The study of glycan function is a major frontier in biology that could benefit from small molecules capable of perturbing carbohydrate structures on cells. The widespread role of Sulfotransferases in modulating glycan function makes them prime targets for small-molecule modulators. Here, we report a system for conditional activation of Golgi-resident Sulfotransferases using a chemical inducer of dimerization. Our approach capitalizes on two features shared by these enzymes: their requirement of Golgi localization for activity on cellular substrates and the modularity of their catalytic and localization domains. Fusion of these domains to the proteins FRB and FKBP enabled their induced assembly by the natural product rapamycin. We applied this strategy to the GlcNAc-6-Sulfotransferases GlcNAc6ST-1 and GlcNAc6ST-2, which collaborate in the sulfation of L-selectin ligands. Both the activity and specificity of the inducible enzymes were indistinguishable from their WT counterparts. We further generated rapamycin-inducible chimeric enzymes comprising the localization domain of a sulfotransferase and the catalytic domain of a glycosyltransferase, demonstrating the generality of the system among other Golgi enzymes. The approach provides a means for studying sulfate-dependent processes in cellular systems and, potentially, in vivo.
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Synthesis of a bisubstrate analogue targeting estrogen sulfotransferase.
Journal of Organic Chemistry, 2003Co-Authors: Joshua I. Armstrong, Dawn E. Verdugo, Carolyn R. BertozziAbstract:Sulfotransferases catalyze the transfer of a sulfuryl group from the eukaryotic sulfate donor 3'-phosphoadenosine 5'-phosphosulfate to an acceptor biomolecule. Sulfotransferases have been linked with several disease states, prompting our investigation of specific sulfotransferase inhibitors. Presented herein is the synthesis and evaluation of a bisubstrate analogue designed to inhibit estrogen sulfotransferase. The synthesis utilizes a novel, orthogonally protected 3'-phosphoadenosine 5'-phosphate (PAP) derivative allowing the selective functionalization of the 5'-phosphate with a sulfate acceptor mimic. Kinetic studies revealed significant inhibitory activity and provide guidance for improved inhibitor design.
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Sulfotransferases and Sulfatases in Mycobacteria
Chemistry & Biology, 2002Co-Authors: Joseph D. Mougous, Richard E. Green, Spencer J. Williams, Steven E. Brenner, Carolyn R. BertozziAbstract:Analysis of the genomes of M. tuberculosis, M. leprae, M. smegmatis, and M. avium has revealed a large family of genes homologous to known Sulfotransferases. Despite reports detailing a suite of sulfated glycolipids in many mycobacteria, a corresponding family of sulfotransferase genes remains uncharacterized. Here, a sequence-based analysis of newly discovered mycobacterial sulfotransferase genes, named stf1-stf10, is presented. Interestingly, two sulfotransferase genes are highly similar to mammalian Sulfotransferases, increasing the list of mycobacterial eukaryotic-like protein families. The Sulfotransferases join an equally complex family of mycobacterial sulfatases: a large family of sulfatase genes has been found in all of the mycobacterial genomes examined. As sulfated molecules are common mediators of cell-cell interactions, the Sulfotransferases and sulfatases may be involved in regulating host-pathogen interactions.
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biosynthesis of l selectin ligands sulfation of sialyl lewis x related oligosaccharides by a family of glcnac 6 Sulfotransferases
Biochemistry, 2001Co-Authors: Kendra G. Bowman, Brian N. Cook, And Christopher L De Graffenried, Carolyn R. BertozziAbstract:The leukocyte adhesion molecule L-selectin mediates lymphocyte homing to secondary lymphoid organs and to certain sites of inflammation. The cognate ligands for L-selectin possess the unusual sulfated tetrasaccharide epitope 6-sulfo sialyl Lewis x (Siaalpha2-->3Galbeta1-->4[Fucalpha1-->3][SO(3)-->6]GlcNAc). Sulfation of GlcNAc within sialyl Lewis x is a crucial modification for L-selectin binding, and thus, the underlying sulfotransferase may be a key modulator of lymphocyte trafficking. Four recently discovered GlcNAc-6-Sulfotransferases are the first candidate contributors to the biosynthesis of 6-sulfo sLex in the context of L-selectin ligands. Here we report the in vitro activity of the four GlcNAc-6-Sulfotransferases on a panel of synthetic oligosaccharide substrates that comprise structural motifs derived from sialyl Lewis x. Each enzyme preferred a terminal GlcNAc residue, and was impeded by the addition of a beta1,4-linked Gal residue (i.e., terminal LacNAc). Surprisingly, for three of the enzymes, significant activity was observed with sialylated LacNAc, and two of the enzymes were capable of detectable sulfation of GlcNAc in the context of sialyl Lewis x. On the basis of these results, we propose possible pathways for 6-sulfo sialyl Lewis x biosynthesis and suggest that sulfation may be an early committed step.
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Sulfotransferases as targets for therapeutic intervention.
Current Opinion in Drug Discovery & Development, 2000Co-Authors: Joshua I. Armstrong, Carolyn R. BertozziAbstract:Sulfated biomolecules regulate a diverse array of normal and pathological cellular communication events. The participation of these bioconjugates in a variety of disease states has sparked interest in the enzyme class that installs the sulfate esters: the Sulfotransferases. Recent advances in the cloning and characterization of sulfotransferase enzymes and our understanding of the role of sulfated biomolecules in disease states have prompted the search for specific sulfotransferase inhibitors. Evidence for the participation of sulfated carbohydrates and proteins in acute and chronic inflammation, tumor progression and microbial pathogenesis is presented herein, followed by a discussion of sulfotransferase mechanism and approaches to inhibiting sulfotransferase activity.
Michael W H Coughtrie - One of the best experts on this subject based on the ideXlab platform.
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sulfation through the looking glass recent advances in sulfotransferase research for the curious
Pharmacogenomics Journal, 2002Co-Authors: Michael W H CoughtrieAbstract:Members of the cytosolic sulfotransferase (SULT) superfamily catalyse the sulfation of a multitude of xenobiotics, hormones and neurotransmitters. Humans have at least 10 functional SULT genes, and a number of recent advances reviewed here have furthered our understanding of SULT function. Analysis of expression patterns has shown that Sulfotransferases are highly expressed in the fetus, and SULTs may in fact be a major detoxification enzyme system in the developing human. The X-ray crystal structures of three SULTs have been solved and combined with mutagenesis experiments and molecular modelling, they have provided the first clues as to the factors that govern the unique substrate specificities of some of these enzymes. In the future these and other studies will facilitate prediction of the fate of chemicals metabolised by sulfation. Variation in sulfation capacity may be important in determining an individual's response to xenobiotics, and there has been an explosion in information on sulfotransferase polymorphisms and their functional consequences, including the influence of SULT1A1 genotype on susceptibility to colorectal and breast cancer. Finally, the first gene knockout experiments with SULTs have recently been described, with the generation of estrogen sulfotransferase deficient mice in which reproductive capacity is compromised. Our improved understanding of these enzymes will have significant benefits in such diverse areas as drug design and development, cancer susceptibility, reproduction and development.
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interactions between dietary chemicals and human Sulfotransferases molecular mechanisms and clinical significance
Drug Metabolism and Disposition, 2001Co-Authors: Michael W H Coughtrie, Laura E JohnstonAbstract:Sulfation plays a major role in the detoxication of xenobiotics as well as in modulating the biological activity of numerous important endogenous chemicals. In contrast to this “chemical defense” function, sulfation is also a key step in the bioactivation of a host of pro-mutagens and pro-carcinogens. These reactions are catalyzed by an expanding family of sulfotransferase (SULT) enzymes, which transfer a sulfuryl moiety from the universal donor 3′-phosphoadenosine 5′-phosphosulfate. Here, we discuss current knowledge of the human sulfotransferase enzyme family, of which at least 11 members have been identified to date, including regulation of expression by endogenous compounds and xenobiotics as well as the molecular basis of polymorphisms in members of the SULT1A (phenol sulfotransferase) family. We also present new data on the inhibition of SULT1A enzymes by dietary chemicals, showing that compounds to which we are exposed regularly, such as epigallocatechin gallate and epicatechin gallate are extremely potent inhibitors of phenol Sulfotransferases ( K i in the nanomolar range for SULT1A1). We found that the mechanism of inhibition by these chemicals varied depending on the individual isoform involved, showing uncompetitive inhibition of SULT1A1 whereas with SULT1A2 and -1A3 they demonstrated mixed type inhibition. Thus, genetic-environmental interactions may play an important role in modulating sulfotransferase activity and in determining individual response to chemicals metabolized by these important enzymes.
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biology and function of the reversible sulfation pathway catalysed by human Sulfotransferases and sulfatases
Chemico-Biological Interactions, 1998Co-Authors: Michael W H Coughtrie, Sheila Sharp, Kaera Maxwell, Nicola InnesAbstract:Abstract Sulfation and sulfate conjugate hydrolysis play an important role in metabolism, and are catalysed by members of the sulfotransferase and sulfatase enzyme super-families. In general, sulfation is a deactivating, detoxication pathway, but for some chemicals the sulfate conjugates are much more reactive than the parent compound. The range of compounds which are sulfated is enormous, yet we still understand relatively little of the function of this pathway. This review summarises current knowledge of the sulfation system and the enzymes involved, and illustrates how heterologous expression of Sulfotransferases (SULTs) and sulfatases is aiding our appreciation of the properties of these important proteins. The role of sulfation in the bioactivation of procarcinogens and promutagens is discussed, and new data on the inhibition of the sulfotransferase(s) involved by common dietary components such as tea and coffee are presented. The genetic and environmental factors which are known to influence the activity and expression of human SULTs and sulfatases are also reviewed.
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Purification and characterization of a canine liver phenol sulfotransferase.
Drug Metabolism and Disposition, 1997Co-Authors: Elizabeth A. Oddy, Gary R. Manchee, Neil M. Freeman, Malcolm A. Ward, Michael W H CoughtrieAbstract:Species differences in the metabolism of xenobiotics can present significant problems for safety and efficacy assessment during the development of new pharmaceutical agents. Identification of animal models for human metabolism and/or toxicology of any particular compound would significantly reduce the extent and cost of animal testing of novel candidate pharmaceuticals. Sulfation is an important pathway for metabolism of xenobiotics and potent endogenous compounds and is catalyzed by members of the sulfotransferase enzyme family. We have purified a phenol sulfotransferase from male dog liver cytosol which sulfates simple phenolic compounds such as 1-naphthol and 4-nitrophenol. On SDS-polyacrylamide gel electrophoresis, the protein had a subunit molecular weight of approximately 32,000 Da and was 34,200 Da by electrospray mass spectrometry. Immunoblot analysis with an anti-peptide antibody specific for the human phenol-sulfating form of phenol sulfotransferase (P-PST, 1A1) suggested the protein was highly homologous to the human P-PST enzyme. This was supported by amino acid sequence analysis of four peptides derived from the purified enzyme and by comparison with sequences of other phenol Sulfotransferases, which showed the highest identity with human and monkey orthologs. Our data illustrate the high degree of conservation of phenol Sulfotransferases across mammalian species and suggest that this dog liver enzyme is more closely related to the human P-PST than equivalent proteins in rats and mice.
Yasushi Yamazoe - One of the best experts on this subject based on the ideXlab platform.
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A Hydroxysteroid Sulfotransferase, St2b2, Is a Skin Cholesterol Sulfotransferase in Mice.
Journal of Biochemistry, 2002Co-Authors: Miki Shimada, Kiyoshi Nagata, Yoshiteru Kamiyama, Akira Sato, Wataru Honma, Yasushi YamazoeAbstract:The mRNA of a sulfotransferase (St2b2) mediating cholesterol sulfation was detected in mouse skin. Recombinant St2b2 also mediated the sulfation of pregnenolone, 3beta-hydroxy-5-cholen-24-oic acid, and dehydroepiandrosterone. St2b2 protein was detected in skin cytosols on Western blotting. The addition of 10 nM TPA to skin epidermal cells from newborn mice resulted in a twofold increase in cholesterol sulfation and concomitantly enhanced the St2b2 content after 40 h. Other candidate cholesterol Sulfotransferases, St2a4 and St2a9, were not detected in skin by RT-PCR. These results indicate that St2b2 is a cholesterol sulfotransferase in mouse skin.
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MOLECULAR CLONING AND EXPRESSION OF AN AMINE SULFOTRANSFERASE CDNA: A NEW GENE FAMILY OF CYTOSOLIC Sulfotransferases IN MAMMALS
Journal of Biochemistry, 1998Co-Authors: Kouichi Yoshinari, Kiyoshi Nagata, Makoto Ogino, Ken-ichi Fujita, Toshifumi Shiraga, Kazuhide Iwasaki, Takehisa Hata, Yasushi YamazoeAbstract:A cDNA of amine sulfotransferase-RB1 (AST-RB1), which efficiently catalyzes 4-phenyl-1,2,3,6-tetrahydropyridine (PTHP) sulfation, has been isolated by immunoscreening of a rabbit liver cDNA library. The cDNA consisted of 1,117 base pairs and encoded a protein of 301 amino acids with a molecular weight of 35,876. The deduced amino acid sequence matched at six positions those of peptide fragments obtained from purified AST-RB1 protein. The sequence had less than 38% identity at the amino acid level with cytosolic Sulfotransferases in mammals, although high degrees of similarity were observed with regions conserved throughout mammalian Sulfotransferases. These results indicate that AST-RB1, arbitrarily named sulfotransferase 3A1 (ST3A1), constitutes a new and third gene family of cytosolic Sulfotransferases in mammals. ST3A1 expressed in Escherichia coli as a fused protein catalyzed sulfation of amines such as PTHP, aniline, 4-chloroaniline, 2-naphthylamine, and desipramine, but barely O-sulfation of typical aryl and hydroxysteroid sulfotransferase substrates. These data unequivocally demonstrate the existence of a cytosolic sulfotransferase showing a high selectivity for amine substrates, and indicate that multiple forms of sulfotransferase mediate sulfation of xenobiotics in mammalian livers.
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molecular cloning and characterization of rat st1b1 and human st1b2 cdnas encoding thyroid hormone Sulfotransferases
Journal of Biochemistry, 1997Co-Authors: Ken-ichi Fujita, Kiyoshi Nagata, Shogo Ozawa, Hironobu Sasano, Yasushi YamazoeAbstract:Human and rat cDNAs encoding thyroid hormone Sulfotransferases have been isolated from their liver cDNA libraries. The isolated Sulfotransferases, termed rat ST1B1 and human ST1B2, share 77 and 74% homologies at nucleotide and deduced amino acid levels. These forms showed less than 36 and 56% homologies to hydroxysteroid and aryl Sulfotransferases, indicating that they constitute a new gene subfamily of aryl sulfotransferase. Expression of ST1B1 and ST1B2 in COS-1 cells resulted in the appearance of 33.0 and 32.5 kDa proteins, respectively, whose mobilities were identical with proteins detected in rat and human livers in Western blots using antibodies raised against ST1B1 and ST1B2 produced in Escherichia coli. The recombinant forms catalyzed sulfation of p-nitrophenol, 3,3',5-triiodothyronine (T3) and dopamine, but not of beta-estradiol and dehydroepiandrosterone. ST1B1 and ST1B2 showed higher affinities for formation of T3 sulfate (apparent Km 40.2 and 63.5 microM, respectively) than did thermostable phenol sulfotransferase ST1A3 (apparent Km 413 microM) or thermolabile phenol sulfotransferase ST1A5 (apparent Km 180 microM). These data indicate that the newly characterized Sulfotransferases constitute a distinct ST1 subfamily of enzymes catalyzing the sulfation of T3 as a typical endogenous substrate in rats and humans.
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Structural similarity and diversity of Sulfotransferases
Chemico-Biological Interactions, 1994Co-Authors: Yasushi Yamazoe, Kiyoshi Nagata, Shogo Ozawa, Ryuichi KatoAbstract:In the present study, four new forms of aryl sulfotransferase cDNAs have been isolated and their structures determined. A compilation of primary structures of 16 different Sulfotransferases, including enzymes metabolizing endogenous chemicals and xenobiotics, showed a considerable extent of similarity among bacterial, plant and mammalian species, and indicates that these enzymes constitute a supergene family. Aryl sulfotransferase and estrogen sulfotransferase are shown to belong to a single gene family (ST1) which consists of at least four subfamilies, whereas, based on the sequence similarity, hydroxysteroid Sulfotransferases constitute a distinct family (ST2). Little or no clear similarity was observed between the primary structures of enzymes N-sulfating aminosugars and those sulfating hydrophobic chemicals such as phenols, alcohols or amines, indicating that both types of enzymes diverged early in their evolutionary history. Two regions in the C-terminal parts are, however, conserved among all enzymes examined, which suggests a possibly essential role of these sites for the binding of a PAPS cofactor or for sulfate transfer.
Mingcheh Liu - One of the best experts on this subject based on the ideXlab platform.
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highly conserved mouse and human brain Sulfotransferases molecular cloning expression and functional characterization
Gene, 2002Co-Authors: Yoichi Sakakibara, Junko Katafuchi, Yasunari Takami, Tatsuo Nakayama, Masahito Suiko, Govind T Pai, Mingcheh LiuAbstract:By employing reverse transcription-polymerase chain reaction (RT-PCR) in conjunction with 5'-rapid amplification of cDNA ends technique, we have cloned a novel mouse sulfotransferase cDNA. Database search led to the identification of a human gene encoding the homologue of this newly discovered mouse sulfotransferase. RT-PCR technique was employed to clone the cDNA encoding the human enzyme. Sequence analysis revealed that the novel mouse and human Sulfotransferases display nearly 98% identity in their amino acid sequences. Their amino acid sequence identity to other known cytosolic Sulfotransferases, however, was found to be below 36%. These two highly conserved Sulfotransferases therefore appear to belong to a family different from the two major mammalian cytosolic sulfotransferase gene families. Northern blot analysis revealed the neuronal tissue-specific expression of these two novel Sulfotransferases. Recombinant mouse and human brain Sulfotransferases, expressed using the pGEX-2TK prokaryotic expression system and purified from transformed Escherichia coli cells, migrated as 33 kD proteins upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Purified mouse and human brain Sulfotransferases displayed enzymatic activities toward endogenous and xenobiotic compounds, including L-triiodothyronine, thyroxine, estrone, p-nitrophenol, 2-naphthylamine, and 2-naphthol. Using mouse brain filtrate as substrate, both brain Sulfotransferases were shown to catalyze specifically the sulfation of only a few compounds.
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Sulfation of environmental estrogen-like chemicals by human cytosolic Sulfotransferases.
Biochemical and Biophysical Research Communications, 2000Co-Authors: Masahito Suiko, Yoichi Sakakibara, Mingcheh LiuAbstract:Abstract To investigate whether sulfation, a major Phase II detoxification pathway in vivo, can be employed as a means for the inactivation/disposal of environmental estrogens, recombinant human cytosolic Sulfotransferases were prepared and tested for enzymatic activities with bisphenol A, diethylstilbestrol, 4-octylphenol, p -nonylphenol, and 17α-ethynylestradiol as substrates. Of the seven recombinant enzymes examined, only SULT1C sulfotransferase #1 showed no activities toward the environmental estrogens tested. Among the other six Sulfotransferases, the simple phenol (P)-form phenol sulfotransferase and estrogen sulfotransferase appeared to be considerably more active toward environmental estrogens than the other four Sulfotransferases. Metabolic labeling experiments revealed the sulfation of environmental estrogens and the release of their sulfated derivatives by HepG2 human hepatoma cells. Moreover, sulfated environmental estrogens appeared to be incapable of penetrating through the HepG2 cell membrane.
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molecular cloning expression and characterization of novel human sult1c Sulfotransferases that catalyze the sulfonation ofn hydroxy 2 acetylaminofluorene
Journal of Biological Chemistry, 1998Co-Authors: Yoichi Sakakibara, Ken Yanagisawa, Junko Katafuchi, David P Ringer, Yasunari Takami, Tatsuo Nakayama, Masahito Suiko, Mingcheh LiuAbstract:Abstract Upon sulfonation, carcinogenic hydroxyarylamines such as N-hydroxy-2-acetylaminofluorene (N-OH-2AAF) can be further activated to form ultimate carcinogens in vivo. Previous studies have shown that a SULT1C1 sulfotransferase is primarily responsible for the sulfonation of N-OH-2AAF in rat liver. In the present study, two novel human Sulfotransferases shown to be members of the SULT1C sulfotransferase subfamily based on sequence analysis have been cloned, expressed, and characterized. Comparisons of the deduced amino acid sequence encoded by the human SULT1C sulfotransferase cDNA 1 reveal 63.7, 61.6, and 85.1% identity to the amino acid sequences of rat SULT1C1 sulfotransferase, mouse SULT1C1 sulfotransferase, and rabbit SULT1C sulfotransferase. In contrast, the deduced amino acid sequence of the human SULT1C sulfotransferase 2 cDNA displays 62.9, 63.1, 63.1, and 62.5% identity to the amino acid sequences of the human SULT1C sulfotransferase 1, rat SULT1C1 sulfotransferase, mouse SULT1C1 sulfotransferase, and rabbit SULT1C sulfotransferase. Recombinant human SULT1C Sulfotransferases 1 and 2, expressed in Escherichia coli and purified to near electrophoretic homogeneity, were shown to cross-react with the antiserum against the rat liver SULT1C1 sulfotransferase and exhibited sulfonating activities with N-OH-2AAF as substrate. Tissue-specific expression of these novel human SULT1C Sulfotransferases were examined by employing the Northern blotting technique. The results provide a foundation for the investigation into the functional relevance of these new SULT1C Sulfotransferases in different human tissues/organs.
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Molecular cloning, expression, and functional characterization of novel mouse Sulfotransferases.
Biochemical and Biophysical Research Communications, 1998Co-Authors: Yoichi Sakakibara, Ken Yanagisawa, Yasunari Takami, Tatsuo Nakayama, Masahito Suiko, Mingcheh LiuAbstract:Nucleotide sequences of two mouse cDNAs encoding new sulfotransferase enzymes were determined. Analysis of the deduced amino acid sequences revealed that one represents a novel member of the phenol sulfotransferase family and the other is highly homologous to human SULT2B1 hydroxysteroid Sulfotransferases. The recombinant enzymes, transiently expressed in COS-7 cells, were characterized with respect to their substrate specificity using a variety of substrates for different types of Sulfotransferases. The tissue-specific expression of these two new mouse Sulfotransferases was examined by Northern blot analysis.
Lars C. Pedersen - One of the best experts on this subject based on the ideXlab platform.
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Engineering Sulfotransferases to modify heparan sulfate
Nature Chemical Biology, 2008Co-Authors: Andrea F. Moon, Lars C. Pedersen, Danyin Song, Jian LiuAbstract:The biosynthesis of heparan sulfate (HS) involves an array of specialized Sulfotransferases. Here, we present a study aimed at engineering the substrate specificity of different HS 3-O-sulfotransferase isoforms. Based on the crystal structures, we identified a pair of amino acid residues responsible for selecting the substrates. Mutations of these residues altered the substrate specificities. Our results demonstrate the feasibility of tailoring the specificity of Sulfotransferases to modify HS with desired functions.
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structure and function of Sulfotransferases
Archives of Biochemistry and Biophysics, 2001Co-Authors: Masahiko Negishi, Evgeniy V. Petrotchenko, Yoshimitsu Kakuta, Lee G. Pedersen, Sergei Shevtsov, Anna Gorokhov, Lars C. PedersenAbstract:Sulfotransferases (STs) catalyze the transfer reaction of the sulfate group from the ubiquitous donor 3'-phosphoadenosine 5'-phosphosulfate (PAPS) to an acceptor group of numerous substrates. This reaction, often referred to as sulfuryl transfer, sulfation, or sulfonation, is widely observed from bacteria to humans and plays a key role in various biological processes such as cell communication, growth and development, and defense. The cytosolic STs sulfate small molecules such as steroids, bioamines, and therapeutic drugs, while the Golgi-membrane counterparts sulfate large molecules including glucosaminylglycans and proteins. We have now solved the X-ray crystal structures of four cytosolic and one membrane ST. All five STs are globular proteins composed of a single alpha/beta domain with the characteristic five-stranded beta-sheet. The beta-sheet constitutes the core of the Paps-binding and catalytic sites. Structural analysis of the PAPS-, PAP-, substrate-, and/or orthovanadate (VO(3-)(4))-bound enzymes has also revealed the common molecular mechanism of the transfer reaction catalyzed by sulfotransferses. The X-ray crystal structures have opened a new era for the study of Sulfotransferases.
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Crystal structure‐based studies of cytosolic sulfotransferase
Journal of Biochemical and Molecular Toxicology, 2001Co-Authors: Kouichi Yoshinari, Evgeniy V. Petrotchenko, Lars C. Pedersen, Masahiko NegishiAbstract:Sulfation is a widely observed biological reaction conserved from bacterium to human that plays a key role in various biological processes such as growth, development, and defense against adversities. Deficiencies due to the lack of the ubiquitous sulfate donor 3′-phosphoadenosine-5′-phosphosulfate (PAPS) are lethal in humans. A large group of enzymes called Sulfotransferases catalyze the transfer reaction of sulfuryl group of PAPS to the acceptor group of numerous biochemical and xenochemical substrates. Four X-ray crystal structures of Sulfotransferases have now been determined: cytosolic estrogen, hydroxysteroid, aryl Sulfotransferases, and a sulfotransferase domain of the Golgi-membrane heparan sulfate N-deacetylase/N-sulfotransferase 1. These have revealed the conserved core structure of the PAPS binding site, a common reaction mechanism, and some information concerning the substrate specificity. These crystal structures introduce a new era of the study of the Sulfotransferases. © 2001 John Wiley & Sons, Inc. J Biochem Mol Toxicol 15:67–75, 2001
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The dimerization motif of cytosolic Sulfotransferases.
FEBS Letters, 2001Co-Authors: Evgeniy V. Petrotchenko, Lars C. Pedersen, Christoph H. Borchers, Kenneth B. Tomer, Masahiko NegishiAbstract:Cytosolic Sulfotransferases sulfate steroids such as estrogens and hydroxysteroids. The enzymes, including human estrogen sulfotransferase (hEST) and hydroxysteroid sulfotransferase (hHST), are generally homodimers in solution with mouse estrogen sulfotransferase (mEST) being one of few exceptions. To identify the amino acid residues responsible for the dimerization, eight residues on the surface of hEST were mutated to their counterparts in mEST and mutated hESTs were then analyzed by gel filtration chromatography. A single mutation of Val269 to Glu was sufficient to convert hEST to a monomer and the corresponding mutation of Val260 also altered hHST to a monomer. The hHST crystal structure revealed a short stretch of peptide with the side-chains from two hHST monomers forming a hydrophobic zipper-like structure enforced by ion pairs at both ends. This peptide consisted of 10 residues near the C-terminus that, including the critical Val residue, is conserved as KXXXTVXXXE in nearly all cytosolic Sulfotransferases. When mEST underwent the double mutations Pro269Thr/Glu270Val dimerization resulted. Thus, the KXXXTVXXXE sequence appears to be the common protein–protein interaction motif that mediates the homo- as well as heterodimerization of cytosolic Sulfotransferases.
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CRYSTAL STRUCTURE OF HUMAN CATECHOLAMINE SULFOTRANSFERASE
Journal of Molecular Biology, 1999Co-Authors: Lisa M Bidwell, Lars C. Pedersen, Michael E. Mcmanus, Andrea Gaedigk, Yoshimitsu Kakuta, Masa Negishi, Jennifer L. MartinAbstract:Sulfonation, like phosphorylation, can modify the activity of a variety of biological molecules. The sulfotransferase enzymes sulfonate neurotransmitters, drugs, steroid hormones, dietary carcinogens and proteins. SULT1A3 specifically sulfonates catecholamines such as dopamine, adrenaline and noradrenaline. The crystal structure of SULT1A3 with a sulfate bound at the active site, has been determined at 2.4 Angstrom resolution. Although the core alpha/beta fold is like that of estrogen and heparan Sulfotransferases, major differences occur in and around the active site. Most notably, several regions Surrounding the active site, including a section of 40 residues, are disordered in SULT1A3. Regions that are topologically equivalent to the disordered parts of SULT1A3 are involved in substrate and cofactor binding in estrogen and heparan sulfotransferase. Flexibility in these regions suggests that ligand binding elicits a disorder-order transition in and around the active site of Sulfotransferases and might contribute to the broad substrate specificity of these enzymes. (C) 1999 Academic Press.
