Phenol sulfotransferase

HARRIS R M, WARING R H, KIRK c J, HUGHES p J (2000) Sulfation of oestrogenic alkylphenols and 17beta-oestradiol by human platelet phenol sulfotransferases. J Biol Chem. 275 159-66. 

Easterbrook, J., Liu, C., Sakai, Y. and Li, A.P. (2001) Effects of organic solvents on the activities of cytochrome P450 isoforms, UDP-dependent glucuronyl transferase, and phenol sulfotransferase in human hepatocytes. Drug Metabolism and Disposition The Biological Fate of Chemicals, 29, 141-144. 

Beckmann JD, Spurzem JR, Rennard SI (1993) Phenol sulfotransferase expression in the airways Enzymological and immunohistochemical demonstration. Cell Tissue Res 274(3) 475 t85. 

Potentially, individuals with low activities of the enzymes phenol sulfotransferase and glucuronyl-transferase may be more susceptible to phenol toxicity. Persons with ulcerative colitis may have an impaired capacity to sulfate phenol (Ramakrishna et al. 1991), which may increase the amount of unchanged phenol that is absorbed following oral exposure. Neonates may also be more susceptible to toxicity from dermally-applied phenol because of increased skin permeability and proportionately greater surface area. A study in which 10-day-old rats were more sensitive to lethality following oral exposure to phenol than 5-week-old or adult rats (Deichmann and Witherup 1944) further suggests that the young may be more sensitive to phenol. (For a more detailed discussion please see Section 2.6.) Because phenol is a vesicant, individuals with sensitive skin or pulmonary incapacity may be more sensitive to phenol. Individuals with kidney or liver diseases that impair metabolism or excretion of phenol and phenol metabolites may be more susceptible to phenol. 

Beckmann JD, Bartzatt R, Ulphani J, et al. 1995. Phenol sulfotransferase activities and localization in human nasal polyp epithelium. Biochem Biophys Res Commun 213 104-111. 

Campbell N, Van Loon JA, Weinshilboum RM. 1987. Human liver phenol sulfotransferase Assay conditions, biochemical properties and partial purification of isozymes of the thermostable form. Biochem Pharmacol 36 1435-1446. 

Heroux JA, Falany CN, and Roth JA. 1989. Immunological characterization of human phenol sulfotransferase. Mol Pharmacol 36 29-33. 

Baranczyk-Kuzma, A., Garren, J.A., Hidalgo, I.J., and Borchardt, R.T., Substrate specificity and some properties of phenol sulfotransferase from human intestinal Caco-2 cells, Life Sci., 49, 1197, 1991. 

Sulfation Alcohols/phenols Sulfotransferases Sulfate esters... 

Lactoylglutathione lyase Phenol-sulfating phenol sulfotransferase 1... 

Quercetin and other flavonols are subject to metabolic conversion during the absorption process in the small intestine. Phase II enzymes including uridine 5 -diphosphate glucuronosyl transferase (UGT), phenol-sulfotransferase (PST),... 

Curcumin has also been found to interrupt the cell cycle, to have cytotoxic effects, and to have a role in antiproliferation and the induction of apoptosis in a hepatocarcinoma cell line. Curcumin is a potent inhibitor of phenol sulfotransferase (SULT1A1) in human liver and extrahepatic tissues [Vietri et al., 2003]. Curcumin inhibited the interleukin-6 (IL-6) production, histone acetyltransferase (HAT) activity, and API activation [Chen et al., 2003a] and prevented cell death and apoptotic biochemical changes, such as the... 

Vietri M, Pietrabissa A, Mosca F, Spisni R, Pacifici GM. 2003. Curcumin is a potent inhibitor of phenol sulfotransferase (SULT1A1) in human liver and extrahepatic tissues. Xenobiotica 33 357-363. 

Different phenol sulfotransferases have been identified in the soluble fraction of especially the liver that use 3 -phosphoadenosine-5 -phosphosulfate as sulfate donor [16]. Examination of the substrate preferences of partially purified phenol sulfotransferases has indicated higher rates of sulfation of 3,3 -T2 than of T, and negligible sulfation of T4 and rT3 [17],... 

Chen et al. (1999,2003) used cytosol prepared from various sections of the human intestine to study the occurrence and distribution of sulfotransferases in the gastrointestinal tract. They fortified the cytosol with PAPS. They utilized the sulfuryl group transfer from p-nitrophenol sulphate to PAP to generate PAPS for measurement of the phenol sulfotransferase activity by measurement of the colored product p-nitro-phenol. Cytosolic incubation were stopped by addition of Tris buffer, pH 8.7. 

Chen GP, Battaglia E, Senay C et al. (1999) Photoaffinity labelling probe for the substrate binding site of human phenol sulfotransferase (SULT1 Al) 7-azido-methyl-coumarin. Prot Sci 8 2151-2157 Chen G, Zhang D, Jing N et al. (2003) Human intestinal sulfotransferases identification and distribution. Toxicol Appl Pharmacol 187 186-197... 

Tabrett CA, Coughtrie MWH (2003) Phenol sulfotransferase 1A1 activity in human liver Kinetic properties, interindividual variation and re-evaluation of the suitability of 4-nitrophenol as a probe substrate. Biochem Pharmacol... 

Thomas NL, Coughthrie MWH (2003) Sulfation of apomor-phine by human sulfotransferases evidence of a major role for the polymorphic phenol sulfotransferase. SULT1A1. Xenobiotica 33 1139-1148... 

Table 4 Drug metabolizing enzyme (P450 isoforms (CYP), UDP-glucuronosyl transferase (UGT) and phenol sulfotransferase (PST)) substrates that can be used for the in situ measurement of activity in the human hepatocyte enzyme induction assay.

Radiolabeled products were separated from substrates by chromatography on a Merck Qg column (5 /an). The mobile phase contained 0.1 M sodium acetate, 0.1 M citric acid, 0.1 mAf sodium octylsulfate, 0.15 mAf EDTA, and 0.2 mAf dibutylamine in 10% methanol (v/v). The pH was 4 for the monoamine oxidase assay and 3.7 for phenol sulfotransferase. A flow-through radioisotope detector was used to quantitate the amount of radioactivity in the eluted peaks. 

The assay for monoamine oxidase contained in a final volume of 100 pL to 30 pL of homogenate and 50 pAf [7-14C] dopamine (0.93 mCi/mmol) or [7-,4C] tyramine (3.11 mCi/mmol) in 0.5 M phosphate buffer (pH 7.4). The assay for phenol sulfotransferase was also initiated by adding 30 pL of homogenate. The mixture contained 1.7 pAf [35S] 3 -phosphoadenosine-5 -phosphosulfate (1.51 Ci/mmol) and 50 pAf dopamine, 3,4-dihydroxyphenylacetic acid, or phenol in 10 mAf phosphate buffer (pH 6.4). After various incubation periods, the activity of either enzyme was stopped by addition of 30 pL of 2 N HC1. The resulting mixtures were centrifuged or filtered before analysis by HPLC. 

Figure 9.18 shows a representative chromatogram of the substrates and products of liver monoamine oxidase activity. Figure 9.19 illustrates results with phenol sulfotransferase activity. 

Figure 9,19 Chromatograms of the cosubstrate (PAPS) and products of liver phenol sulfotransferase activity. Upper tracing a, PAPS, b, sulfate-conjugated dopamine. Middle tracing a, PAPS, b, sufate-conjugated Dopac. Lower tracing a, PAPS, b, sulfate-conjugated phenol. The retention time for sulfate-conjugated dopamine, Dopac, and phenol was 4.5, 6.8, and 7.0 minutes, respectively. (From Sim and Hsu, 1990.)...

Phenolsulfotransferase catalyzes the transfer of active sulfate from 3 -phosphoadensine 5 -phosphosulfate to various phenols and catechols. Honkasalo and Nissinen (1988) developed an assay that is suitable for measuring both the thermolabile (TL) and thermostable (TS) isoforms of phenol sulfotransferase. Both are active toward phenols, while the TL form also conjugates catechols including dopamine. 

Phenol sulfotransferases estrogen sulfotransferase Cytosol S9 hepatocytes... 

Harris, R.M., R.H. Waring, C.J. Kirk and P.J. Hughes. Sulfation of estrogenic alkylphenols and 17/3-estradiol by human platelet phenol sulfotransferases. J. Biol. Chem. 275 159-166, 2000. 

The sulfotransferases are a family of enzymes (39), separable by ammonium sulfate fractionation Into a group conjugating phenolic substrates (39) and another group responsible for steroid sulfation ( ). The phenol sulfotransferase fraction contains at least four distinct enzyme forms, specifically catalysing the sulfation of various substrates Including phenols, N-hydroxyacetamldes and oestrone. 

Introduction. Sulfation reactions consist of a sulfate being transferred from the cofactor 3 -phosphoadenosine 5 -phosphosulfate (19) (PAPS Fig. 13.17)to the substrate under catalysis by a sulfotransferase. The three criteria of conjugation are met in these reactions. Sulfotransferases, which catalyze a variety of physiological reactions, are soluble enzymes that include aryl sulfotransferase (phenol sulfotransferase EC 2.8.2.1), alcohol sulfotransferase (hydroxysteroid sulfotransferase EC... 

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