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1.
J Agric Food Chem ; 72(28): 15971-15984, 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-38959404

ABSTRACT

Myristicin (MYR) mainly occurs in nutmeg and belongs to alkoxy-substituted allylbenzenes, a class of potentially toxic natural chemicals. RNA interaction with MYR metabolites in vitro and in vivo has been investigated in order to gain a better understanding of MYR toxicities. We detected two guanosine adducts (GA1 and GA2), two adenosine adducts (AA1 and AA2), and two cytosine adducts (CA1 and CA2) by LC-MS/MS analysis of total RNA extracts from cultured primary mouse hepatocytes and liver tissues of mice after exposure to MYR. An order of nucleoside adductions was found to be GAs > AAs > CAs, and the result of density functional theory calculations was in agreement with that detected by the LC-MS/MS-based approach. In vitro and in vivo studies have shown that MYR was oxidized by cytochrome P450 enzymes to 1'-hydroxyl and 3'-hydroxyl metabolites, which were then sulfated by sulfotransferases (SULTs) to form sulfate esters. The resulting sulfates would react with the nucleosides by SN1 and/or SN2 reactions, resulting in RNA adduction. The modification may alter the biochemical properties of RNA and disrupt RNA functions, perhaps partially contributing to the toxicities of MYR.


Subject(s)
Activation, Metabolic , Allylbenzene Derivatives , Cytochrome P-450 Enzyme System , RNA , Sulfotransferases , Tandem Mass Spectrometry , Animals , Mice , Sulfotransferases/metabolism , Sulfotransferases/genetics , Sulfotransferases/chemistry , Cytochrome P-450 Enzyme System/metabolism , Cytochrome P-450 Enzyme System/genetics , Cytochrome P-450 Enzyme System/chemistry , Allylbenzene Derivatives/chemistry , Allylbenzene Derivatives/metabolism , RNA/metabolism , RNA/chemistry , Male , Hepatocytes/metabolism , Dioxolanes/metabolism , Dioxolanes/chemistry , Dioxolanes/toxicity , Liver/metabolism , Liver/enzymology , Disulfides/chemistry , Disulfides/metabolism , Myristica/chemistry , Myristica/metabolism
2.
Int J Mycobacteriol ; 13(1): 73-82, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38771283

ABSTRACT

BACKGROUND: Tuberculosis (TB) remains a prominent global health challenge, distinguished by substantial occurrences of infection and death. The upsurge of drug-resistant TB strains underscores the urgency to identify novel therapeutic targets and repurpose existing compounds. Rv0295c is a potentially druggable enzyme involved in cell wall biosynthesis and virulence. We evaluated the inhibitory activity of Food and Drug Administration (FDA)-approved compounds against Rv0295c of Mycobacterium tuberculosis, employing molecular docking, ADME evaluation, and dynamics simulations. METHODS: The study screened 1800 FDA-approved compounds and selected the top five compounds with the highest docking scores. Following this, we subjected the initially screened ligands to ADME analysis based on their dock scores. In addition, the compound exhibited the highest binding affinity chosen for molecular dynamics (MD) simulation to investigate the dynamic behavior of the ligand-receptor complex. RESULTS: Dihydroergotamine (CHEMBL1732) exhibited the highest binding affinity (-12.8 kcal/mol) for Rv0295c within this set of compounds. We evaluated the stability and binding modes of the complex over extended simulation trajectories. CONCLUSION: Our in silico analysis demonstrates that FDA-approved drugs can serve as potential Rv0295c inhibitors through repurposing. The combination of molecular docking and MD simulation offers a comprehensive understanding of the interactions between ligands and the protein target, providing valuable guidance for further experimental validation. Identifying Rv0295c inhibitors may contribute to new anti-TB drugs.


Subject(s)
Antitubercular Agents , Molecular Docking Simulation , Molecular Dynamics Simulation , Mycobacterium tuberculosis , United States Food and Drug Administration , Mycobacterium tuberculosis/enzymology , Mycobacterium tuberculosis/drug effects , Antitubercular Agents/pharmacology , Antitubercular Agents/chemistry , United States , Sulfotransferases/metabolism , Sulfotransferases/chemistry , Sulfotransferases/antagonists & inhibitors , Bacterial Proteins/chemistry , Bacterial Proteins/metabolism , Drug Approval , Humans , Ligands , Tuberculosis/microbiology , Tuberculosis/drug therapy
3.
Biochem Biophys Res Commun ; 711: 149891, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38621346

ABSTRACT

Microorganisms synthesize a plethora of complex secondary metabolites, many of which are beneficial to human health, such as anticancer agents and antibiotics. Among these, the Sungeidines are a distinct class of secondary metabolites known for their bulky and intricate structures. They are produced by a specific biosynthetic gene cluster within the genome of the soil-dwelling actinomycete Micromonospora sp. MD118. A notable enzyme in the Sungeidine biosynthetic pathway is the activating sulfotransferase SgdX2. In this pathway, SgdX2 mediates a key sulfation step, after which the product undergoes spontaneous dehydration to yield a Sungeidine compound. To delineate the structural basis for SgdX2's substrate recognition and catalytic action, we have determined the crystal structure of SgdX2 in complex with its sulfate donor product, 3'-phosphoadenosine 5'-phosphate (PAP), at a resolution of 1.6 Å. Although SgdX2 presents a compact overall structure, its core elements are conserved among other activating sulfotransferases. Our structural analysis reveals a unique substrate-binding pocket that accommodates bulky, complex substrates, suggesting a specialized adaptation for Sungeidine synthesis. Moreover, we have constructed a substrate docking model that provides insights into the molecular interactions between SgdX2 and Sungeidine F, enhancing our understanding of the enzyme's specificity and catalytic mechanism. The model supports a general acid-base catalysis mechanism, akin to other sulfotransferases, and underscores the minor role of disordered regions in substrate recognition. This integrative study of crystallography and computational modeling advances our knowledge of microbial secondary metabolite biosynthesis and may facilitate the development of novel biotechnological applications.


Subject(s)
Sulfotransferases , Sulfotransferases/metabolism , Sulfotransferases/chemistry , Sulfotransferases/genetics , Crystallography, X-Ray , Models, Molecular , Bacterial Proteins/chemistry , Bacterial Proteins/metabolism , Bacterial Proteins/genetics , Protein Conformation , Substrate Specificity , Catalytic Domain
4.
J Biol Chem ; 300(3): 105748, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38354785

ABSTRACT

Ticks pose a substantial public health risk as they transmit various pathogens. This concern is related to the adept blood-sucking strategy of ticks, underscored by the action of the anticoagulant, madanin, which is known to exhibit an approximately 1000-fold increase in anticoagulant activity following sulfation of its two tyrosine residues, Tyr51 and Tyr54. Despite this knowledge, the molecular mechanism underlying sulfation by tick tyrosylprotein sulfotransferase (TPST) remains unclear. In this study, we successfully prepared tick TPST as a soluble recombinant enzyme. We clarified the method by which this enzyme proficiently sulfates tyrosine residues in madanin. Biochemical analysis using a substrate peptide based on madanin and tick TPST, along with the analysis of the crystal structure of the complex and docking simulations, revealed a sequential sulfation process. Initial sulfation at the Tyr51 site augments binding, thereby facilitating efficient sulfation at Tyr54. Beyond direct biochemical implications, these findings considerably improve our understanding of tick blood-sucking strategies. Furthermore, combined with the utility of modified tick TPST, our findings may lead to the development of novel anticoagulants, promising avenues for thrombotic disease intervention and advancements in the field of public health.


Subject(s)
Anticoagulants , Arthropod Proteins , Sulfotransferases , Ticks , Animals , Anticoagulants/chemistry , Sulfotransferases/chemistry , Tyrosine/metabolism , Arthropod Proteins/chemistry , Crystallization
5.
Biosci Biotechnol Biochem ; 88(4): 368-380, 2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38271594

ABSTRACT

Organisms have conversion systems for sulfate ion to take advantage of the chemical features. The use of biologically converted sulfonucleotides varies in an evolutionary manner, with the universal use being that of sulfonate donors. Sulfotransferases have the ability to transfer the sulfonate group of 3'-phosphoadenosine 5'-phosphosulfate to a variety of molecules. Cytosolic sulfotransferases (SULTs) play a role in the metabolism of low-molecular-weight compounds in response to the host organism's living environment. This review will address the diverse functions of the SULT in evolution, including recent findings. In addition to the diversity of vertebrate sulfotransferases, the molecular aspects and recent studies on bacterial and plant sulfotransferases are also addressed.


Subject(s)
Phosphoadenosine Phosphosulfate , Sulfotransferases , Sulfotransferases/chemistry , Cytosol/metabolism , Phosphoadenosine Phosphosulfate/metabolism , Sulfates/metabolism
6.
BMC Biol ; 21(1): 151, 2023 07 10.
Article in English | MEDLINE | ID: mdl-37424015

ABSTRACT

BACKGROUND: Chronic kidney disease (CKD) accelerates atherosclerosis, but the mechanisms remain unclear. Tyrosine sulfation has been recognized as a key post-translational modification (PTM) in regulation of various cellular processes, and the sulfated adhesion molecules and chemokine receptors have been shown to participate in the pathogenesis of atherosclerosis via enhancement of monocyte/macrophage function. The levels of inorganic sulfate, the essential substrate for the sulfation reaction, are dramatically increased in patients with CKD, which indicates a change of sulfation status in CKD patients. Thus, in the present study, we detected the sulfation status in CKD patients and probed into the impact of sulfation on CKD-related atherosclerosis by targeting tyrosine sulfation function. RESULTS: PBMCs from individuals with CKD showed higher amounts of total sulfotyrosine and tyrosylprotein sulfotransferase (TPST) type 1 and 2 protein levels. The plasma level of O-sulfotyrosine, the metabolic end product of tyrosine sulfation, increased significantly in CKD patients. Statistically, O-sulfotyrosine and the coronary atherosclerosis severity SYNTAX score positively correlated. Mechanically, more sulfate-positive nucleated cells in peripheral blood and more abundant infiltration of sulfated macrophages in deteriorated vascular plaques in CKD ApoE null mice were noted. Knockout of TPST1 and TPST2 decreased atherosclerosis and peritoneal macrophage adherence and migration in CKD condition. The sulfation of the chemokine receptors, CCR2 and CCR5, was increased in PBMCs from CKD patients. CONCLUSIONS: CKD is associated with increased sulfation status. Increased sulfation contributes to monocyte/macrophage activation and might be involved in CKD-related atherosclerosis. Inhibition of sulfation may suppress CKD-related atherosclerosis and is worthy of further study.


Subject(s)
Atherosclerosis , Sulfotransferases , Mice , Animals , Sulfotransferases/chemistry , Sulfotransferases/genetics , Sulfotransferases/metabolism , Proteins/metabolism , Tyrosine/metabolism , Mice, Knockout , Receptors, Chemokine/metabolism , Atherosclerosis/complications , Protein Processing, Post-Translational
7.
J Ind Microbiol Biotechnol ; 50(1)2023 Feb 17.
Article in English | MEDLINE | ID: mdl-37327079

ABSTRACT

The chemo-enzymatic and enzymatic synthesis of heparan sulfate and heparin are considered as an attractive alternative to the extraction of heparin from animal tissues. Sulfation of the hydroxyl group at position 2 of the deacetylated glucosamine is a prerequisite for subsequent enzymatic modifications. In this study, multiple strategies, including truncation mutagenesis based on B-factor values, site-directed mutagenesis guided by multiple sequence alignment, and structural analysis were performed to improve the stability and activity of human N-sulfotransferase. Eventually, a combined variant Mut02 (MBP-hNST-NΔ599-602/S637P/S741P/E839P/L842P/K779N/R782V) was successfully constructed, whose half-life at 37°C and catalytic activity were increased by 105-fold and 1.35-fold, respectively. After efficient overexpression using the Escherichia coli expression system, the variant Mut02 was applied to N-sulfation of the chemically deacetylated heparosan. The N-sulfation content reached around 82.87% which was nearly 1.88-fold higher than that of the wild-type. The variant Mut02 with high stability and catalytic efficiency has great potential for heparin biomanufacturing.


Subject(s)
Sulfates , Sulfotransferases , Animals , Humans , Sulfotransferases/genetics , Sulfotransferases/chemistry , Sulfotransferases/metabolism , Heparin
8.
J Chem Inf Model ; 63(11): 3340-3349, 2023 06 12.
Article in English | MEDLINE | ID: mdl-37229540

ABSTRACT

Cytosolic sulfotransferases (SULTs) are a family of enzymes responsible for the sulfation of small endogenous and exogenous compounds. SULTs contribute to the conjugation phase of metabolism and share substrates with the uridine 5'-diphospho-glucuronosyltransferase (UGT) family of enzymes. UGTs are considered to be the most important enzymes in the conjugation phase, and SULTs are an auxiliary enzyme system to them. Understanding how the regioselectivity of SULTs differs from that of UGTs is essential from the perspective of developing novel drug candidates. We present a general ligand-based SULT model trained and tested using high-quality experimental regioselectivity data. The current study suggests that, unlike other metabolic enzymes in the modification and conjugation phases, the SULT regioselectivity is not strongly influenced by the activation energy of the rate-limiting step of the catalysis. Instead, the prominent role is played by the substrate binding site of SULT. Thus, the model is trained only on steric and orientation descriptors, which mimic the binding pocket of SULT. The resulting classification model, which predicts whether a site is metabolized, achieved a Cohen's kappa of 0.71.


Subject(s)
Sulfotransferases , Catalysis , Binding Sites , Sulfotransferases/chemistry , Sulfotransferases/metabolism
9.
Biochemistry ; 61(10): 843-855, 2022 05 17.
Article in English | MEDLINE | ID: mdl-35523209

ABSTRACT

Among human cytosolic sulfotransferases, SULT2B1b is highly specific for oxysterols─oxidized cholesterol derivatives, including nuclear-receptor ligands causally linked to skin and neurodegerative diseases, cancer and atherosclerosis. Sulfonation of signaling oxysterols redirects their receptor-binding functions, and controlling these functions is expected to prove valuable in disease prevention and treatment. SULT2B1b is distinct among the human SULT2 isoforms by virtue of its atypically long N-terminus, which extends 15 residues beyond the next longest N-terminus in the family. Here, in silico studies are used to predict that the N-terminal extension forms an allosteric pocket and to identify potential allosteres. One such allostere, quercetin, is used to confirm the existence of the pocket and to demonstrate that allostere binding inhibits turnover. The structure of the pocket is obtained by positioning quercetin on the enzyme, using spin-label-triangulation NMR, followed by NMR distance-constrained molecular dynamics docking. The model is confirmed using a combination of site-directed mutagenesis and initial-rate studies. Stopped-flow ligand-binding studies demonstrate that inhibition is achieved by stabilizing the closed form of the enzyme active-site cap, which encapsulates the nucleotide, slowing its release. Finally, endogenous oxysterols are shown to bind to the site in a highly selective fashion─one of the two immediate biosynthetic precursors of cholesterol (7-dehydrocholesterol) is an inhibitor, while the other (24-dehydrocholesterol) is not. These findings provide insights into the allosteric dialogue in which SULT2B1b participates in in vivo and establishes a template against which to develop isoform-specific inhibitors to control SULT2B1b biology.


Subject(s)
Oxysterols , Sulfotransferases , Allosteric Site , Cholesterol/chemistry , Cholesterol/metabolism , Humans , Oxysterols/chemistry , Oxysterols/metabolism , Quercetin/chemistry , Quercetin/metabolism , Sulfotransferases/chemistry , Sulfotransferases/metabolism
10.
Am J Physiol Cell Physiol ; 322(6): C1166-C1175, 2022 06 01.
Article in English | MEDLINE | ID: mdl-35417268

ABSTRACT

Heparan sulfate is a widely expressed polysaccharide in the extracellular matrix and on the cell surface. 3-O-sulfated heparan sulfate represents only a small percentage of heparan sulfate from biological sources. However, this subpopulation is closely associated with biological functions of heparan sulfate. The 3-O-sulfated heparan sulfate is biosynthesized by heparan sulfate 3-O-sulfotransferase, which exists in seven different isoforms. This review article summarizes the recent progress in the substrate specificity studies of different 3-O-sulfotransferase isoforms involving the use of homogeneous oligosaccharide substrates and crystal structural analysis. The article also reviews a newly developed liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based method to analyze the level of 3-O-sulfated heparan sulfate with high sensitivity and quantitative capability. This newly emerged technology will provide new tools to study the structure and function relationship of heparan sulfate.


Subject(s)
Sulfates , Tandem Mass Spectrometry , Chromatography, Liquid , Heparitin Sulfate/metabolism , Protein Isoforms , Sulfotransferases/chemistry , Sulfotransferases/metabolism
11.
ACS Chem Biol ; 17(5): 1207-1214, 2022 05 20.
Article in English | MEDLINE | ID: mdl-35420777

ABSTRACT

Heparan sulfate (HS) and chondroitin sulfate (CS) are two structurally distinct natural polysaccharides. Here, we report the synthesis of a library of seven structurally homogeneous HS and CS chimeric dodecasaccharides (12-mers). The synthesis was accomplished using six HS biosynthetic enzymes and four CS biosynthetic enzymes. The chimeras contain a CS domain on the reducing end and a HS domain on the nonreducing end. The synthesized chimeras display anticoagulant activity as measured by both in vitro and ex vivo experiments. Furthermore, the anticoagulant activity of H/C 12-mer 5 is reversible by protamine, a U.S. Food and Drug Administration-approved polypeptide to neutralize anticoagulant drug heparin. Our findings demonstrate the synthesis of unnatural HS-CS chimeric oligosaccharides using natural biosynthetic enzymes, offering a new class of glycan molecules for biological research.


Subject(s)
Chondroitin Sulfates , Sulfotransferases , Anticoagulants , Chimera , Chondroitin Sulfates/chemistry , Heparitin Sulfate/chemistry , Sulfotransferases/chemistry
12.
Int J Biol Macromol ; 201: 47-58, 2022 Mar 15.
Article in English | MEDLINE | ID: mdl-34998873

ABSTRACT

Heparosan, with a linear chain of disaccharide repeating units of â†’ 4) ß-D-glucuronic acid (GlcA) (1 â†’ 4)-α-D-N-acetylglucosamine (GlcNAc) (1→, is a potential starting chemical for heparin synthesis. However, the chemoenzymatic synthesis of single-site sulfated heparosan and its antitumor activity have not been studied. In this study, 2-deacetyl-3-O-sulfo-heparosan (DSH) was prepared successively by the N-deacetylation chemical reaction and enzymatic modification of human 3-O-sulfotransferase-1 (3-OST-1). Structural characterization of DSH was shown the success of the sulfation with the sulfation degree of 0.87. High performance gel permeation chromatography (HPGPC) analysis revealed that DSH had only one symmetrical sharp peak with a molecular weight of 9.6334 × 104 Da. Biological function studies showed that DSH could inhibit tumor cell (A549, HepG2 and HCT116) viability and induce the apoptosis of A549 cells. Further in vitro mechanistic studies showed that DSH may induce apoptosis via the JNK signaling pathway, and the upstream signal of this process may be fibroblast growth factor receptors. These results indicated that DSH could be developed as one of a potential chemical for tumor treatment.


Subject(s)
Disaccharides , Receptors, Fibroblast Growth Factor , A549 Cells , Disaccharides/chemistry , Disaccharides/metabolism , Humans , Molecular Weight , Sulfotransferases/chemistry , Sulfotransferases/metabolism
13.
ChemMedChem ; 17(9): e202200043, 2022 05 04.
Article in English | MEDLINE | ID: mdl-35080134

ABSTRACT

The sulfotransferase (SULT) 2B1b, which catalyzes the sulfonation of 3ß-hydroxysteroids, has been identified as a potential target for prostate cancer treatment. However, a major limitation for SULT2B1b-targeted drug discovery is the lack of robust assays compatible with high-throughput screening and inconsistency in reported kinetic data. For this reason, we developed a novel label-free assay based on high-throughput (>1 Hz) desorption electrospray ionization mass spectrometry (DESI-MS) for the direct quantitation of the sulfoconjugated product (CV<10 %; <1 ng analyte). The performance of this DESI-based assay was compared against a new fluorometric coupled-enzyme method that we also developed. Both methodologies provided consistent kinetic data for the reaction of SULT2B1b with its major substrates, indicating the affinity trend pregnenolone>DHEA>cholesterol, for both the phospho-mimetic and wild-type SULT2B1b forms. The novel DESI-MS assay developed here is likely generalizable to other drug discovery efforts and is particularly promising for identification of SULT2B1b inhibitors with potential as prostate cancer therapeutics.


Subject(s)
Prostatic Neoplasms , Spectrometry, Mass, Electrospray Ionization , Biological Assay , Humans , Kinetics , Male , Sulfotransferases/chemistry , Sulfotransferases/metabolism
14.
Org Biomol Chem ; 20(3): 596-605, 2022 01 19.
Article in English | MEDLINE | ID: mdl-34951618

ABSTRACT

Sulfotransferases constitute a ubiquitous class of enzymes which are poorly understood due to the lack of a convenient tool for screening their activity. These enzymes use the anion PAPS (adenosine-3'-phosphate-5'-phosphosulfate) as a donor for a broad range of acceptor substrates, including carbohydrates, producing sulfated compounds and PAP (adenosine-3',5'-diphosphate) as a side product. We present a europium(III)-based probe that binds reversibly to both PAPS and PAP, producing a larger luminescence enhancement with the latter anion. We exploit this greater emission enhancement with PAP to demonstrate the first direct real-time assay of a heparan sulfate sulfotransferase using a multi-well plate format. The selective response of our probe towards PAP over structurally similar nucleoside phosphate anions, and over other anions, is investigated and discussed. This work opens the possibility of investigating more fully the roles played by this enzyme class in health and disease, including operationally simple inhibitor screening.


Subject(s)
Coordination Complexes/metabolism , Europium/metabolism , Phosphoadenosine Phosphosulfate/metabolism , Sulfotransferases/metabolism , Anions/chemistry , Anions/metabolism , Cations/chemistry , Cations/metabolism , Coordination Complexes/chemistry , Europium/chemistry , Molecular Structure , Phosphoadenosine Phosphosulfate/chemistry , Sulfotransferases/chemistry , Time Factors
15.
Molecules ; 26(21)2021 Oct 21.
Article in English | MEDLINE | ID: mdl-34770768

ABSTRACT

The aim of this study was to investigate the chemical space and interactions of natural compounds with sulfotransferases (SULTs) using ligand- and structure-based in silico methods. An in-house library of natural ligands (hormones, neurotransmitters, plant-derived compounds and their metabolites) reported to interact with SULTs was created. Their chemical structures and properties were compared to those of compounds of non-natural (synthetic) origin, known to interact with SULTs. The natural ligands interacting with SULTs were further compared to other natural products for which interactions with SULTs were not known. Various descriptors of the molecular structures were calculated and analyzed. Statistical methods (ANOVA, PCA, and clustering) were used to explore the chemical space of the studied compounds. Similarity search between the compounds in the different groups was performed with the ROCS software. The interactions with SULTs were additionally analyzed by docking into different experimental and modeled conformations of SULT1A1. Natural products with potentially strong interactions with SULTs were outlined. Our results contribute to a better understanding of chemical space and interactions of natural compounds with SULT enzymes and help to outline new potential ligands of these enzymes.


Subject(s)
Biological Products/chemistry , Molecular Docking Simulation , Molecular Dynamics Simulation , Sulfotransferases/chemistry , Biological Products/pharmacology , Cluster Analysis , Flavonoids , Ligands , Molecular Structure , Polyphenols , Structure-Activity Relationship , Sulfotransferases/metabolism
16.
Phys Chem Chem Phys ; 23(41): 23850-23860, 2021 Oct 27.
Article in English | MEDLINE | ID: mdl-34647946

ABSTRACT

Tyrosine sulfation alters the biological activity of many proteins involved in different physiological and pathophysiological conditions, such as non-specific immune reaction, response to inflammation and ischemia, targeting of leukocytes and stem cells, or the formation of cancer metastases. Tyrosine sulfation is catalyzed by the enzymes tyrosylprotein sulfotransferases (TPST). In this study, we used QM/MM Car-Parrinello metadynamics simulations together with QM/MM potential energy calculations to investigate the catalytic mechanism of isoform TPST-1. The structural changes along the reaction coordinate are analyzed and discussed. Furthermore, both the methods supported the SN2 type of catalytic mechanism. The reaction barrier obtained from CPMD metadynamics was 12.8 kcal mol-1, and the potential energy scan led to reaction barriers of 11.6 kcal mol-1 and 13.7 kcal mol-1 with the B3LYP and OPBE functional, respectively. The comparison of the two methods (metadynamics and potential energy scan) may be helpful for future mechanistic studies. The insight into the reaction mechanism of TPST-1 might help with the rational design of transition-state TPST inhibitors.


Subject(s)
Sulfotransferases/chemistry , Biocatalysis , Catalytic Domain , Humans , Molecular Dynamics Simulation , Quantum Theory , Thermodynamics
17.
ACS Chem Biol ; 16(10): 2026-2035, 2021 10 15.
Article in English | MEDLINE | ID: mdl-34351732

ABSTRACT

Heparan sulfate (HS) 3-O-sulfotransferase isoform 4 (3-OST-4) is a specialized carbohydrate sulfotransferase participating in the biosynthesis of heparan sulfate. Here, we report the expression and purification of the recombinant 3-OST-4 enzyme and use it for the synthesis of a library of 3-O-sulfated hexasaccharides and 3-O-sulfated octasaccharides. The unique structural feature of the library is that each oligosaccharide contains a disaccharide domain with a 2-O-sulfated glucuronic acid (GlcA2S) and 3-O-sulfated glucosamine (GlcNS3S). By rearranging the order of the enzymatic modification steps, we demonstrate the synthesis of oligosaccharides with different saccharide sequences. The structural characterization was completed by electrospray ionization mass spectrometry and NMR. These 3-O-sulfated oligosaccharides show weak to very weak anti-Factor Xa activity, a measurement of anticoagulant activity. We discovered that HSoligo 7 (HS oligosaccharide 7), a 3-O-sulfated octasaccharide, binds to high mobility group box 1 protein (HMGB1) and tau protein, both believed to be involved in the process of inflammation. Access to the recombinant 3-OST-4 expands the capability of the chemoenzymatic method to synthesize novel 3-O-sulfated oligosaccharides. The oligosaccharides will become valuable reagents to probe the biological functions of 3-O-sulfated HS and to develop HS-based therapeutic agents.


Subject(s)
Oligosaccharides/chemical synthesis , Sulfotransferases/chemistry , Animals , Carbohydrate Sequence , Factor Xa/metabolism , Factor Xa Inhibitors/chemical synthesis , Factor Xa Inhibitors/metabolism , HMGB1 Protein/metabolism , Isoenzymes/chemistry , Mice , Oligosaccharides/metabolism , Recombinant Proteins/chemistry , Sf9 Cells , tau Proteins/metabolism
18.
Methods Mol Biol ; 2342: 285-300, 2021.
Article in English | MEDLINE | ID: mdl-34272699

ABSTRACT

The cytosolic sulfotransferase (SULT) enzymes are found in human liver, kidney, intestine, and other tissues. These enzymes catalyze the transfer of the -SO3 group from 3'-phospho-adenosyl-5'-phosphosulfate (PAPS) to a nucleophilic hydroxyl or amine group in a drug substrate. SULTs are stable as dimers, with a highly conserved dimerization domain near the C-terminus of the protein. Crystal structures have revealed flexible loop regions in the native proteins, one of which, located near the dimerization domain, is thought to form a gate that changes position once PAPS is bound to the PAPS-binding site and modulates substrate access and enzyme properties. There is also evidence that oxidation and reduction of certain cysteine residues reversibly regulate the binding of the substrate and PAPS or PAP to the enzyme thus modulating sulfonation. Because SULT enzymes have two substrates, the drug and PAPS, it is common to report apparent kinetic constants with either the drug or the PAPS varied while the other is kept at a constant concentration. The kinetics of product formation can follow classic Michaelis-Menten kinetics, typically over a narrow range of substrate concentrations. Over a wide range of substrate concentrations, it is common to observe partial or complete substrate inhibition with SULT enzymes. This chapter describes the function, tissue distribution, structural features, and properties of the human SULT enzymes and presents examples of enzyme kinetics with different substrates.


Subject(s)
Sulfotransferases/chemistry , Sulfotransferases/metabolism , Xenobiotics/pharmacology , Binding Sites , Crystallography, X-Ray , Humans , Kinetics , Models, Molecular , Protein Binding , Protein Conformation , Protein Domains , Protein Multimerization , Tissue Distribution , Xenobiotics/chemistry
19.
Commun Biol ; 4(1): 674, 2021 06 03.
Article in English | MEDLINE | ID: mdl-34083726

ABSTRACT

The terminal galactose residues of N- and O-glycans in animal glycoproteins are often sialylated and/or fucosylated, but sulfation, such as 3-O-sulfated galactose (3-O-SGal), represents an additional, but poorly understood modification. To this end, we have developed a novel sea lamprey variable lymphocyte receptor (VLR) termed O6 to explore 3-O-SGal expression. O6 was engineered as a recombinant murine IgG chimera and its specificity and affinity to the 3-O-SGal epitope was defined using a variety of approaches, including glycan and glycoprotein microarray analyses, isothermal calorimetry, ligand-bound crystal structure, FACS, and immunohistochemistry of human tissue macroarrays. 3-O-SGal is expressed on N-glycans of many plasma and tissue glycoproteins, but recognition by O6 is often masked by sialic acid and thus exposed by treatment with neuraminidase. O6 recognizes many human tissues, consistent with expression of the cognate sulfotransferases (GAL3ST-2 and GAL3ST-3). The availability of O6 for exploring 3-O-SGal expression could lead to new biomarkers for disease and aid in understanding the functional roles of terminal modifications of glycans and relationships between terminal sulfation, sialylation and fucosylation.


Subject(s)
Epitopes/metabolism , Galactose/analogs & derivatives , Glycoproteins/metabolism , Lampreys/metabolism , Polysaccharides/metabolism , Amino Acid Sequence , Animals , CHO Cells , Cricetinae , Cricetulus , Fucose/metabolism , Galactose/metabolism , Glycoproteins/chemistry , Glycosylation , HEK293 Cells , Humans , Lampreys/immunology , Ligands , Mass Spectrometry/methods , N-Acetylneuraminic Acid/metabolism , Sulfates/metabolism , Sulfotransferases/chemistry , Sulfotransferases/genetics , Sulfotransferases/metabolism
20.
Biotechnol Lett ; 43(9): 1831-1844, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34176028

ABSTRACT

OBJECTIVES: Heparosan is used as the starting polysaccharide sulfated using sulfotransferase to generate fully elaborate heparin, a widely used clinical drug. However, the preparation of heparosan and enzymes was considered tedious since such material must be prepared in separate fermentation batches. In this study, a commonly admitted probiotic, Escherichia coli strain Nissle 1917 (EcN), was engineered to intracellularly express sulfotransferases and, simultaneously, secreting heparosan into the culture medium. RESULTS: The engineered strain EcN::T7M, carrying the λDE3 region of BL21(DE3) encoding T7 RNA polymerase, expressed the sulfotransferase domain (NST) of human N-deacetylase/N-sulfotransferase-1 (NDST-1) and the catalytic domain of mouse 3-O-sulfotransferase-1 (3-OST-1) in a flask. The fed-batch fermentation of EcN::T7M carrying the plasmid expressing NST was carried out, which brought the yield of NST to 0.21 g/L and the yield of heparosan to 0.85 g/L, respectively. Furthermore, the heparosan was purified, characterized by 1H nuclear magnetic resonance (NMR), and sulfated by NST using 3'-phosphoadenosine-5'-phosphosulfate (PAPS) as the sulfo donor. The analysis of element composition showed that over 80% of disaccharide repeats of heparosan were N-sulfated. CONCLUSIONS: These results indicate that EcN::T7M is capable of preparing sulfotransferase and heparosan at the same time. The EcN::T7M strain is also a suitable host for expressing exogenous proteins driven by tac promoter and T7 promoter.


Subject(s)
Disaccharides/metabolism , Escherichia coli/growth & development , Heparin/metabolism , Sulfotransferases/genetics , Animals , Batch Cell Culture Techniques , Escherichia coli/genetics , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Fermentation , Genetic Engineering , Humans , Mice , Protein Domains , Sulfotransferases/chemistry , Sulfotransferases/metabolism
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