Phosphosulfate

ATP interacts with sulfate ion (SO ) to form adenosine 5-phosphosulfate (APS) in a reaction mediated by the enzyme ATP sulfate adenylyl transferase. 

Abbreviations NADPH, b-nicotinamide adenine dinucleotide phosphate reduced from 5 -phosphosulfate UDPGA, uridine diphosphate-glucuronic acid. 

Some alcohols, arylamines, and phenols are sulfated. The sulfate donor in these and other biologic sulfation reactions (eg, sulfation of steroids, glycosaminoglycans, glycolipids, and glycoproteins) is adenosine 3 -phos-phate-S -phosphosulfate (PAPS) (Chapter 24) this compound is called active sulfate. ... 

FIGURE 6.3 Quantification on the first half of an isolated peak. The spectrum is from the [2Fe-2S] cluster in the enzyme adenosine phosphosulfate reductase from Desulfovibrio vulgaris (Verhagen et al. 1993). The inset shows the asymmetrical low-field -feature the vertical line at the peak position indicates the rightmost integration limit for quantification on half... 

FIGURE 13.6 Whole bacterial-cell EPR. A frozen concentrated suspension of cells from the sulfate-reducing bacterium Desulfovibrio vulgaris gives an EPR spectrum with only a [2Fe-2S]1+ signal and a flavin radical signal, both from adenosine phosphosulfate reductase. 

Verhagen, M.F.J.M., Kooter, I.M., Wolbert, R.B.G., and Hagen, W.R. 1993. On the iron-sulfur cluster of adenosine phosphosulfate reductase from Desulfovibrio vulgaris (Hildenborough). European Journal of Biochemistry 221 831-837. 

L-cysteine. The process is completed by glucosylation and addition of S03 at the nitrogen (Equation 10) by reaction with 3 -phospho-adenosine-5 -phosphosulfate. 

Conjugations can also be brought about by sulfotransferases (SULTs) and glutathi-one-S-transferases (GSTs), both of which exist in a number of isoenzymic forms. Amines and alcohols are sulfate acceptors and SULTs are important in steroid hormone and catecholamine metabolism and like the UGTs require the sulfate to be activated prior to its incorporation into the target molecule (Figure 6.32). In this case, sulfate is activated at the expense of two molecules of ATP to form the final sulfate carrier PAPS O -phosphoadenosine-S -phosphosulfate). 

Kim HJ, Cho JH, Klaassen CD. 1995. Depletion of hepatic 3 -phosphoadenosine 5 -phosphosulfate (PAPS) and sulfate in rats by xenobiotics that are sulfated. J Pharmacol Exp Ther 275 654-658. 

Lyric RM, Suzuki I. 1970. Enzymes involved in the metabolism of thiosulfate by Thiobacillus thioparus. II. Properties of adenosine 5 -phosphosulfate reductase. Can J Biochem 48 344-54. 

Peck HD. 1960. Adenosine 5 -phosphosulfate as an intermediate in the oxidation of thiosulfate by Thiobacillus thioparus. Proc Nat Acad Sci USA 46 1053-7. 

Peck HD, Deacon TE, Davidson JT. 1965. Studies on adenosine 5 -phosphosulfate reductase from Desulfovibrio desulfuricans and Thiobacillus thioparus. Biochim Biophys Acta 96 429 7. 

Soluble cytoplasmic sulfotrans-ferases conjugate activated sulfate (3 -phosphoadenine-5 -phosphosulfate) with alcohols and phenols. The conjugates are acids, as in the case of glucuronides. In this respect, they differ from conjugates formed by acetyltransfe-rases from activated acetate (acetyl-coenzyme A) and an alcohol or a phenol... 

The biosynthesis of sulfate esters with the help of phosphoadenosine phosphosulfate (PAPS), the active sulfate , (see p. 110) and amide formation with glycine and glutamine also play a role in conjugation. For example, benzoic acid is conjugated with glycine to form the more soluble and less toxic hippuric acid (N-benzoylglycine see p. 324). 

ADP NADH Disappearance Pyruvate Kinase, Lactate Dehydrogenase, and 3 -Nucleo-tidase Adenosine-5 -phosphosulfate Kinase ... 

Sulfotransferases (SULTs) are important for the metabolism of a number of drugs, neurotransmitters, and hormones, especially the steroid hormones. The cosubstrate for these reactions is 3 -phosphoadenosine 5 -phosphosulfate (PAPS) (Fig. 4.1). Like the aforementioned enzymes, sulfate conjugation typically renders the compound inactive and more water soluble. However, this process can also result in the activation of certain compounds, such as the antihypertensive minoxidil and several of the steroid hormones. Seven SULT isoforms identified in humans, including SULTs lAl to 1A3, possess activity toward phenolic substrates such as dopamine, estradiol, and acetaminophen. SULTIBI possesses activity toward such endogenous substrates as dopamine and triiodothyronine. SULTIEI has substantial activity toward steroid hormones, especially estradiol and dehydroepiandrosterone, and toward the anti-... 

Marsolais, F. et al., 3 -Phosphoadenosine 5 -phosphosulfate binding site of flavonol 3-sulfotrans-ferase studied by affinity chromatography and P-31 NMR. Biochemistry, 38, 4066, 1999. 

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