An expanded set of fluorogenic sulfatase activity probes

Fluorogenic probes that are activated by an enzymatic transformation are ideally suited for profiling enzyme activities in biological systems. Here, we describe two fluorogenic enzyme probes, 3-O-methylfluorescein-sulfate and resorufin-sulfate, that can be used to detect sulfatases in mycobacterial lysates. Both probes were validated with a set of commercial sulfatases and used to reveal species-specific sulfatase banding patterns in a gel-resolved assay of mycobacterial lysates. The fluorogenic probes described here are suitable for various assays and provide a starting point for creating new sulfatase probes with improved selectivity for mycobacterial sulfatases.

Inter and intra plant variability of enzyme profiles including various phosphoesterases and sulfatase of six wastewater treatment plants

Biodegradation of organic wastewater constituents by activated sludge microorganisms is based on enzymatic processes. It is supposed that wastewater treatment plants (WWTP) differ in their enzymatic fingerprints. To determine such fingerprints, activated sludges from nine aerated tanks of six WWTPs were repeatedly sampled and analyzed for the activities of l-alanine aminopeptidase, esterase, α- and β-glucosidase, alkaline phosphatase, phosphodiesterase, phosphotriesterase, and sulfatase. In one WWTP the enzymatic activities and their variations within 1 week were assayed in various process stages. Mostly the enzymatic profiles were dominated by l-alanine aminopeptidase, followed by alkaline phosphatase. They differed in variable contributions of esterase, phosphodiesterase, α- and β-glucosidase. The sulfatase activity was generally low. For the first time phosphotriesterase activity was detected in various samples, but with limited analytical validity. Particle mass-related activities of individual enzymes varied between plants by factors 2-4 and up to 11, when related to suspension volumes.

Serial magnetic resonance imaging and neurophysiological studies in multiple sulphatase deficiency

We present serial clinical, magnetic resonance imaging (MRI) and neurophysiological findings of a patient with multiple sulphatase deficiency (MSD), who was first admitted at the age of 9 months, because of psychomotor retardation. MRI demonstrated extensive diffuse symmetrical high signal in the deep white matter of both cerebral hemispheres, as well as of the subcortical white matter and the brainstem, while there was additional enlargement of sulci and subdural spaces and mild atrophy. Assay of arylsulphatase A activity in white blood cell homogenates at the age of 29 months disclosed a marked deficiency of the enzyme, compatible with the diagnosis of early-infantile metachromatic leukodystrophy. During the course of a later admission, the presence of ichthyosis pointed out to the possible diagnosis of MSD; further assays of sulphatases in plasma, leukocytes as well as in cultured fibroblasts, combined with an abnormal excretion of mucopolysaccharides and sulphatides in urine confirmed the diagnosis. Molecular analysis identified a homozygous disease-causing mutation (R349W) of the SUMF1 gene. Serial neurophysiological and MRI studies demonstrated the progressive nature of the disorder (regarding both central and peripheral nervous system), correlating with the clinical deterioration (spastic quadriplegia, optic atrophy and epilepsy) with subsequent death at the age of 4 years.

Sulfatase modifying factor 1 trafficking through the cells: from endoplasmic reticulum to the endoplasmic reticulum

Sulfatase modifying factor 1 (SUMF1) is the gene mutated in multiple sulfatase deficiency (MSD) that encodes the formylglycine-generating enzyme, an essential activator of all the sulfatases. SUMF1 is a glycosylated enzyme that is resident in the endoplasmic reticulum (ER), although it is also secreted. Here, we demonstrate that upon secretion, SUMF1 can be taken up from the medium by several cell lines. Furthermore, the in vivo engineering of mice liver to produce SUMF1 shows its secretion into the blood serum and its uptake into different tissues. Additionally, we show that non-glycosylated forms of SUMF1 can still be secreted, while only the glycosylated SUMF1 enters cells, via a receptor-mediated mechanism. Surprisingly, following its uptake, SUMF1 shuttles from the plasma membrane to the ER, a route that has to date only been well characterized for some of the toxins. Remarkably, once taken up and relocalized into the ER, SUMF1 is still active, enhancing the sulfatase activities in both cultured cells and mice tissues.

A novel bacterial mucinase, glycosulfatase, is associated with bacterial vaginosis

The modifications to the vaginal habitat accompanying a change to vaginal flora in bacterial vaginosis (BV) are poorly understood. In this study enzymes involved in mucin degradation were measured, including a novel glycosulfatase assay. Women attending an emergency walk-in sexually transmitted disease clinic were studied. One high vaginal swab (HVS) was used to prepare a gram-stained smear to determine BV status, using Ison and Hay's criteria, and a separate swab was used for the purposes of the assays. The median glycosulfatase activity was 8.5 (range, -1.2 to 31.9) nmol h(-1) 1.5 ml(-1) of HVS suspension in patients with BV compared to 0.5 (range, -0.7 to 9.4) nmol h(-1) 1.5 ml(-1) of HVS suspension in patients without BV (P = <0.001). The median glycoprotein sialidase activity was 29.2 (range, -17 to 190) nmol h(-1) 1.5 ml(-1) of HVS suspension in patients with BV compared to -1.1 (range, -41 to 48) nmol h(-1) 1.5 ml(-1) of HVS suspension in patients without BV (P < 0.001). A rapid spot test for sialidase was positive in 22/24 patients with BV (sensitivity, 91.7%; 95% confidence interval [CI], 73 to 99%) and negative in 32/35 patients without BV (specificity, 91.4%; 95% CI, 76.9 to 98.2%) (P < 0.001). Glycosulfatase activity significantly correlated with both glycoprotein sialidase activity and the sialidase spot test (P = 0.006 and P < 0.001, respectively). The results are consistent with the hypothesis that the consortium of bacteria present in BV requires the ability to break down mucins in order to colonize the vagina and replace the normal lactobacilli.

Sulphatase activities are regulated by the interaction of sulphatase-modifying factor 1 with SUMF2

Sulphatases undergo a unique post-translational modification that converts a highly conserved cysteine located within their active site into formylglycine. This modification is necessary for the catalytic activities of the sulphatases, and it is generated by the protein product of sulphatase-modifying factor 1 (SUMF1), the gene mutated in multiple sulphatase deficiency (MSD). A paralogous gene, SUMF2, was discovered through its sequence similarity to SUMF1. We present evidence that SUMF2 colocalizes with SUMF1 within the endoplasmic reticulum and that the two proteins form heterodimers. SUMF1 and SUMF2 also form homodimers. In addition, SUMF2 is able to associate with the sulphatases with and without SUMF1. We have previously shown that co-transfection of SUMF1 with the sulphatase complementary DNAs greatly enhances the activities of the overexpressed sulphatases. Here, we show that SUMF2 inhibits the enhancing effects of SUMF1 on sulphatases, suggesting that the SUMF1-SUMF2 interaction represents a further level of control of these sulphatase activities.

Sulfatase activity in the oyster Crassostrea virginica: its potential interference with sulfotransferase determination

Two sulfatase isoforms, a soluble one with an optimum pH of 5.0, and a microsomal one with an optimum pH of 7.6, were observed in digestive gland, gonads, mantle and gills of the oyster C. virginica. The highest sulfatase activity was recorded in the digestive gland cytosol and is likely to interfere with the in vitro determination of sulfotransferase activity. Indeed, the sulfatase inhibitor Na(2)SO(3) led to an increase of measured sulfotransferase activity (31+/-9%), suggesting that those sulfatases might be partially responsible for the low sulfotransferase activities found in C. virginica.

A fluorogenic substrate for the continuous assaying of aryl sulfatases

The most common fluorogenic substrate for assaying aryl sulfatases (ARSs) is 4-methylumbelliferyl sulfate (MUS). However, ARSs operate optimally at pH values that are less than the pK(a) (7.8) of the reaction product of MUS, 4-methylumbelliferone (4-MU). Thus, a major disadvantage of this assay is that it is usually run in a discontinuous mode due to the need for basification of the reaction mixture to achieve complete ionization of the phenolic products and maximum fluorescence. To circumvent this problem, 6,8-difluoro-4-methylumbelliferyl sulfate (DiFMUS) was prepared and examined as a substrate for ARSs. The product of the reaction is 6,8-difluoro-4-methylumbelliferone, a known coumarin with fluorescent properties equal to those of 4-MU, and has a pK(a) of 4.9. This allowed for the continuous assaying of human placental ARSs A, B, and C, which operate optimally between pH 5.0 and pH 7.0. Furthermore, DiFMUS exhibited a lower K(m) (up to 20-fold) for the ARSs than did MUS; for ARSA and ARSB, it exhibited a greater V(max) than did MUS. This substrate should have considerable utility for the continuous assay of ARS activity.

Metabolism of sulfolipids in isolated renal tubules from rat

Proximal-rich tubules were prepared from rat kidneys by using collagenase treatment. The isolated rat renal tubules were compared with the intact kidney on the following characteristics. (1) Composition of the sulfoglycolipid. (2) Sulfoglycolipid metabolism based on incorporation of [35S]sulfate or some properties of sulfoglycolipid metabolism, including the activities of anabolic and catabolic enzymes. The results indicated following characteristics of the isolated renal tubules in comparison to the kidney in vivo. (1) The sulfoglycolipid compositions are qualitatively similar, except that the content of glucosyl sulfatide, Gg3Cer II3-sulfate, and GM4 was slightly higher in the isolated tubules. (2) The apparent half-lives (15-55 min) of sulfoglycolipids in the isolated tubules could indicate the existence of a rapid turnover pool of these lipids. (3) The sulfotransferase and sulfatase activities related to sulfoamphiphiles in the renal tubule were similar to those reported for the whole kidney. Based on the above criteria, we conclude that the isolated rat renal tubule should be a useful metabolic system for clarification of the short-term physiological events, up to 90 min, of proximal tubular sulfoglycolipids. By using the present system, we showed that biosynthesis of the renal total sulfoglycolipid was significantly elevated in rats deprived of water for 24 h.

Caprine Mucopolysaccharidosis IIID: Fetal and Neonatal Brain and Liver Glycosaminoglycan and Morphological Perturbations

Mucopolysaccharidosis IIID (MPS IIID) is a lysosomal storage disease associated with deficient activity of the enzyme N-acetylglucosamine 6-sulfatase (EC 3.1.6.14), a lysosomal hydrolase in the heparan sulfate glycosaminoglycan (HS-GAG) degradation pathway. In caprine MPS IIID, enzyme replacement therapy reversed early postnatal systemic but not primary or secondary central nervous system (CNS) substrate accumulations. The caprine MPS IIID large animal model system was used in this investigation to define the developmental profile of morphological and biochemical perturbations to estimate a time frame for therapeutic intervention. Light and electron microscopy were used to compare the CNS, liver, and kidney of normal +/+, MPS IIID carrier +/-, and MPS IIID-affected -/- goat kids (kids), at 60, 113-114, 128-129, and 135 d gestation (dg) of a 150-d gestational period, at birth, and at 59-64 d of postnatal (d-pn) age. In the CNS of -/- kids, morphological correlations of HS-GAG and glycolipid accumulations were evident in early differentiating neurons at 60 dg. CNS and systemic developmental, regional, and cellular differences in -/- kids at all time points included more prominent and earlier accumulation of lucent, putative HS-GAG substrates in lysosomes of meningeal and perivascular macrophages and hepatic sinusoidal cells than in CNS, hepatic, or renal parenchymal cells. The amounts and compositions of HS-GAG substrates in the brain and liver of +/+, +/-, and -/- kids were determined at 60, 65, 113-114, and 128-135 dg, at birth, and 53-78 d-pn. In the CNS of -/- kids, HS-GAG concentrations were variable and exceeded those of age-matched control tissue samples in the third but not the second trimester. In contrast, hepatic HS-GAG levels in -/- kids exceeded control values at all time points evaluated and paralleled the progressive morphological alterations. CNS and hepatic HS-GAG compositions in -/- kids were similar to each other and were more complex at all pre- and postnatal ages than those from control kids. Based on the time frame of development of CNS lesions and biochemical perturbations, prenatal therapeutic intervention in caprine MPS IIID is likely to be necessary to prevent or ameliorate substantive CNS and systemic lesions.

Immunohistologic localization of estrone sulfatase in uterine endometrium and adenomyosis

OBJECTIVE

To clarify histologic localization of estrone sulfatase in normal uterine endometrium and adenomyotic tissue and to confirm that estrone sulfatase is one of the enzymes that supplies estrogen to adenomyotic tissue.

METHODS

Specimens from 21 patients who had undergone hysterectomy were obtained from uteri with histopathologically proven adenomyosis. Specimens from 28 patients who had undergone hysterectomy for a disease of the uterine cervix were used as control specimens of normal uterine endometrium. Cases of hormone-dependent disease, such as leiomyoma, adenomyosis, and endometrial neoplasm, were excluded from cases of normal endometrium. The myometrium in patients with adenomyosis was examined. These tissues were examined by immunohistochemistry using anti-estrone sulfatase monoclonal antibodies. Power analysis was performed. With alpha = 0.05, 1 - beta = 0.8, P1= 25%, and P2 = 75%, 14 specimens from each group were sufficient to detect significant differences among them. The Fisher exact test, sign test, and McNemar test were used for statistical analysis.

RESULTS

In normal endometrial tissue, immunostaining for estrone sulfatase was observed only on the glandular epithelial cells of the basilar layer of the endometrium. However, all functional layers of the endometria were negative for staining for estrone sulfatase. In adenomyotic tissue, glandular epithelial cells showed immunostaining for estrone sulfatase. Rates of immunostaining in adenomyotic tissue were higher than those in the basilar layer of normal uterine endometrium (76% and 43%, respectively, P =.02). The myometrium was not stained.

CONCLUSION

Estrone sulfatase may be one of the enzymes supplying estrogen for growth of adenomyosis.

Change in rate-determining step in an E1cB mechanism during aminolysis of sulfamate esters in acetonitrile

The kinetics of the reactions of the nitrogen-sulfur(VI) esters 4-nitrophenyl N-methylsulfamate (NPMS) with a series of pyridines and a series of alicyclic amines and of 4-nitrophenyl N-benzylsulfamate (NPBS) with pyridines, alicyclic amines, and a series of quinuclidines have been investigated in acetonitrile (ACN) in the presence of excess amine at various temperatures. Pseudo-first-order rate constants (k(obsd)) have been obtained by monitoring the release of 4-nitrophenol/4-nitrophenoxide. From the slope of a plot of k(obsd) vs [amine], second-order rate constants (k'(2)) have been obtained for the pyridinolysis of NPMS, and a Brønsted plot of log k'(2) vs pK(a) of pyridine gave a straight line with beta = 0.45. However, aminolysis with alicyclic amines of NPMS gave a biphasic Brønsted plot (beta(1) = 0.6, beta(2) approximately equal to 0). Pyridinolysis and aminolysis with alicyclic amines and quinuclidines of NPBS also gave similar biphasic Brønsted plots. This biphasic behavior has been explained in terms of a mechanistic change within the E1cB mechanism from an (E1cB)(irrev) (less basic amines) to an (E1cB)(rev) (more basic amines), and the change occurs at approximately the pK(a)'s (in ACN) of NPMS (17.94) and NPBS (17.68). The straight line Brønsted plot for NPMS with pyridines occurs because the later bases are not strong enough to substantially remove the substrate proton and initiate the mechanistic change observed in the reaction of NPMS with the strong alicyclic amines and quinuclidines. An entropy study supports the change from a bimolecular to a unimolecular mechanism. This is the first clear demonstration of this E1cB mechanistic changeover involving a nitrogen acid substrate.

Development of potent non-estrogenic estrone sulfatase inhibitors

Estrogen levels in breast tumors of post-menopausal women are as much as 10 times higher than estrogen levels in plasma, presumably due to in situ formation of estrogen. The major source of estrogen in breast cancer cells may be conversion of estrone sulfate to estrone by the enzyme estrone sulfatase. Thus, inhibitors of estrone sulfatase have potential for the treatment of estrogen-dependent breast cancers. Several steroidal agents have been developed that are potent estrone sulfatase inhibitors, most notably estrone-3-O-sulfamate. These compounds may have undesired actions, especially estrogenicity. Recently, non-steroidal estrone sulfatase inhibitors have been designed that avoid the problems associated with an active steroid nucleus; however, these have not achieved the potency of estrone-3-O sulfamate. We have designed and synthesized a series of compounds, 17 beta-(N-alkylcarbamoyl)-estra-1,3,5(10)-trien-3-O-sulfamates (6a-d) and 17 beta-(N-alkanoyl)-estra-1,3,5(10)-trien-3-O-sulfamates (11a-d) that combine the structural features of the steroidal estrone sulfatase inhibitors with a membrane insertion region that should increase the affinity for the sulfatase enzyme and decrease the estrogenicity of the steroid. We tested the compounds for estrone sulfatase inhibition by measuring estrone sulfatase activity in intact cultures of human breast cancer cells (MDA-MB-231). We tested for estrogenicity by measuring growth of estrogen-dependent MCF-7 human breast cancer cells. All of the test compounds (10 nM) substantially inhibited estrogen sulfatase activity of intact MDA-MB-231 cells. Dose-response analysis indicated an IC50 of approximately 0.5 nM for two of the compounds (6a and 11a). In the test for estrogenicity, estrone and estrone-3-O-sulfamate significantly stimulated MCF-7 cell growth. In contrast, neither the 17 beta-(N-alkylcarbamoyl)-estra-1,3,5,(10)-trien-3-O-sulfamates++ + nor the 17 beta-(N)-alkanoyl)-estra-1,3,5,(10)-trien-3-O-sulfamates stimulated growth of MCF-7 cells at a concentration of 1 microM, indicating that they are not estrogenic at levels 2000 times greater than their IC50 for estrone sulfatase. Our data indicate the utility of the new compounds for inhibition of breast cancer cell estrone sulfatase activity. Further, our data support the concept that estrone sulfatase inhibitors may be useful as therapeutic agents for estrogen-dependent breast cancers.

Anomalous decrease in dextran sulfate clearance in the diabetic rat kidney

The anomalous increase in charge selectivity as previously observed with reduced dextran sulfate clearances in diabetic rats (L. D. Michels, M. Davidman, and W. F. Keane. Kidney Int. 21: 699-705, 1982) was confirmed in 4-wk streptozotocin (STZ) diabetic Sprague-Dawley rats using the isolated perfused kidney technique. The apparent charge selectivity in both control and diabetic rats could be abolished by increasing the dextran sulfate concentration to 200 micrograms/ml in the perfusate. This was demonstrated by a high rate of processing of dextran sulfate (approximately 1,700 ng.min-1.kidney-1) by glomeruli in both control and diabetic kidneys and by the fact that charge interaction could not explain the concentration dependence. The amount of urinary desulfation of dextran sulfate was also found to be significantly less in the diabetic kidney as was glomerular sulfatase activity compared with controls. Dextran sulfate glomerular processing is therefore altered in the STZ diabetic rat kidney but could be rationalized in terms of previous models of endothelial cell receptor-mediated uptake of dextran sulfate. The results are consistent with recent work demonstrating that there is little or no electrostatic charge interaction operating on dextran sulfate or other negatively charged molecules at the glomerular capillary wall.

Ichthyosis: the skin manifestation of multiple sulfatase deficiency

Juvenile sulfatidosis (Austin type) or multiple sulfatase deficiency is an extremely rare autosomal recessive disorder affecting the activity of many sulfatases: arylsulfatase A, several mucopolysaccharide sulfatases, and steroid sulfatase. Certain aspects of the clinical phenotype can be attributed mainly to a deficiency of one specific sulfatase. Most patients develop metachromatic leukodystrophy caused by arylsulfatase A deficiency, dysostosis multiplex by mucopolysaccharide sulfatase deficiency, and ichthyotic skin by steroid sulfatase deficiency. We describe a 7-year-old boy with developmental delay from 7 months of age, progressive spastic quadriparesis, and coarse facial features. By 27 months of age, an ichthyotic rash had developed on the limbs, trunk, and scalp. A skin biopsy specimen revealed hyperkeratosis with a normal granular layer. The diagnosis of multiple sulfatase deficiency was demonstrated by measuring sulfatase activities in fresh leukocytes: there were large deficiencies of arylsulfatase A and B plus reduced arylsulfatase C. The ichthyosis associated with multiple sulfatase deficiency has an autosomal recessive inheritance, is caused by steroid sulfatase deficiency, and the scaling is sometimes milder than in X-linked recessive ichthyosis. This could reflect the residual activity of steroid sulfatase in some cases.

Effect of nomegestrol acetate on estrone-sulfatase and 17beta-hydroxysteroid dehydrogenase activities in human breast cancer cells

It is well recognized that estradiol (E2) is one of the most important hormones supporting the growth and evolution of breast cancer. Consequently, to block this hormone before it enters the cancer cell or in the cell itself, has been one of the main targets in recent years. In the present study we explored the effect of the progestin, nomegestrol acetate, on the estrone sulfatase and 17beta-hydroxysteroid dehydrogenase (17beta-HSD) activities of MCF-7 and T-47D human breast cancer cells. Using physiological doses of estrone sulfate (E1S: 5 x 10(-9)M), nomegestrol acetate blocked very significantly the conversion of E1S to E2. In the MCF-7 cells, using concentrations of 5 x 10(-6)M and 5 x 10(-5) M of nomegestrol acetate, the decrease of E1S to E2 was, respectively, -43% and -77%. The values were, respectively, -60% and -71% for the T-47D cells. Using E1S at 2 x 10(-6) M and nomegestrol acetate at 10(-5) M, a direct inhibitory effect on the enzyme of -36% and -18% was obtained with the cell homogenate of the MCF-7 and T-47D cells, respectively. In another series of studies, it was observed that after 24 h incubation of a physiological concentration of estrone (E1: 5 x 10(-9)M) this estrogen is converted in a great proportion to E2. Nomegestrol acetate inhibits this transformation by -35% and -85% at 5 x 10(-7)M and 5 x 10(-5)M, respectively in T-47D cells; whereas in the MCF-7 cells the inhibitory effect is only significant, -48%, at 5 x 10(-5)M concentration of nomegestrol acetate. It is concluded that nomegestrol acetate in the hormone-dependent MCF-7 and T-47D breast cancer cells significantly inhibits the estrone sulfatase and 17beta-HSD activities which converts E1S to the biologically active estrogen estradiol. This inhibition provoked by this progestin on the enzymes involved in the biosynthesis of E2 can open new clinical possibilities in breast cancer therapy.

SDS-degrading bacteria attach to riverine sediment in response to the surfactant or its primary biodegradation product dodecan-1-ol

A laboratory-scale river microcosm was used to investigate the effect of the anionic surfactant sodium dodecyl sulphate (SDS) on the attachment of five Pseudomonas strains to natural river-sediment surfaces. Three of the Pseudomonas strains were chosen for their known ability to express alkylsulphatase enzymes capable of hydrolysing SDS, and the other two for their lack of such enzymes. One strain from each category was isolated from the indigenous bacterial population present in the river sediment used; other isolates were from soil or sewage. The alkylsulphatase phenotypes were confirmed by gel zymography of cell extracts. Addition of SDS to mixed suspensions of river sediment with any one of the biodegradation-competent strains stimulated the attachment of bacteria to the sediment particles. In contrast, the attachment of biodegradation-incompetent strains was weak and, moreover, was unaffected by SDS. The SDS-stimulated attachment for competent organisms coincided with rapid biodegradation of the surfactant. The primary intermediate of SDS biodegradation, dodecan-1-ol, accumulated transiently, and the numbers of attached bacteria correlated closely with the amount of dodecan-1-ol present. Direct addition of dodecan-1-ol also stimulated attachment but the effect was more immediate compared with SDS, when there was a lag period of approximately 2 h. To account for these observations, a model is proposed in which SDS stimulates the attachment of biodegradation-competent bacteria through its conversion to dodecan-1-ol, and it is hypothesized that the observed reversibility of the attachment is due to the subsequent removal of dodecan-1-ol by further bacterial metabolism.

Immunochemical characterization of feline and human N-acetylgalactosamine 4-sulfatase

Maroteaux-Lamy syndrome (mucopolysaccharidosis type VI; MPS VI) is a disorder which results from a deficiency in the lysosomal associated enzyme N-acetylgalactosamine 4-sulfatase (4-sulfatase). A feline model of human MPS VI has previously been described and provides a system for the evaluation of enzyme replacement therapy protocols. As a preliminary study to human 4-sulfatase enzyme replacement therapy in feline we have compared the immunochemical properties of human and feline 4-sulfatase. By SDS-PAGE the molecular mass of purified feline and human 4-sulfatase were similar under both reducing and nonreducing conditions. There was, however, a detectable conformation difference between human and feline 4-sulfatase indicating some structural variation. Feline 4-sulfatase reacted weakly with a panel of monoclonal antibodies in an immunobinding assay (interacting with 4-sulfatase in free solution), but the same monoclonal antibodies reacted strongly with feline 4-sulfatase in an immunoquantification assay where the feline 4-sulfatase was bound to a polyclonal antibody (which presumably induces a conformation change in the feline 4-sulfatase to closer approximate the structure of human 4-sulfatase). A monoclonal antibody which selectively reacts with human 4-sulfatase has been used to develop an assay suitable for evaluating human 4-sulfatase enzyme replacement in cat tissues.

Widespread tissue distribution of steroid sulfatase, 3 beta-hydroxysteroid dehydrogenase/delta 5-delta 4 isomerase (3 beta-HSD), 17 beta-HSD 5 alpha-reductase and aromatase activities in the rhesus monkey

Dehydroepiandrosterone-sulfate (DHEA-S), the main secretory product of the human adrenal, requires the presence of steroid sulfatase, 3 beta-hydroxysteroid dehydrogenase/delta 5-delta 4 isomerase (3 beta-HSD), 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD), 5 alpha-reductase, and aromatase to form the active androgen dihydrotestosterone (DHT) and the estrogens 17 beta-estradiol (E2) and 5-androst-ene-3 beta,17 beta-diol (delta 5-diol) in peripheral target tissues. Because humans, along with non-human primates are unique in having adrenals that secrete large amounts of DHEA-S, the present study investigated the tissue distribution of the enzymatic activity of the above-mentioned steroidogenic enzymes required for the formation of active sex steroids in the male and female rhesus monkey. Estrone and DHEA sulfatase activities were measured in all 25 tissues examined, and with the exception of the salivary glands, estrogenic and androgenic 17 beta-HSDs were present in all the tissues examined. The adrenal, small and large intestine, kidney, liver, lung, fat, testis, prostate, seminal vesicle, ovary, myometrium, and endometrium all possess the above-mentioned enzymatic activities, thus suggesting that these tissues could possibly form the biologically active steroids E2 and DHT from the adrenal precursor DHEA-S. On the other hand, the oviduct, cervix, mammary gland, heart, and skeletal muscle possess all the enzymatic activities required to synthesize E2 from DHEA-S. The present study describes the widespread tissue distribution of steroid sulfatase, 3 beta-HSD, 17 beta-HSD, 5 alpha-reductase, and aromatase activities in rhesus monkey peripheral tissues.(ABSTRACT TRUNCATED AT 250 WORDS)

Intratumoral oestrone sulphatase activity as a prognostic marker in human breast carcinoma

Oestrone sulphatase is an important source of local synthesis of biologically active oestrogens in human breast cancer. The oestrone sulphatase enzyme in the particulate fraction of human breast carcinoma was characterised. The Km was 8.91 microM, and the Vmax was 0.022 nmol min-1 mg-1. Oestrone sulphatase activity was detected in 93 of 104 human breast carcinoma samples (89%), and mean activity was 0.041 nmol min-1 mg-1 (range 0-0.399 nmol min-1 mg-1). There was no significant correlation between intratumoral oestrone sulphatase activity and oestrogen receptor status, or with any other prognostic factors. Intratumoral enzyme levels were not associated with time to recurrence or with overall survival time. It thus appears that, although a useful source of intratumoral oestrogens, oestrone sulphatase activity is not of prognostic significance in breast carcinoma.

Prognostic significance of aromatase and estrone sulfatase enzymes in human breast cancer

The aromatase and estrone sulfatase enzymes are important sources of local synthesis of biologically active estrogens in human breast cancer. Significant intratumoral aromatase activity was detected in 91/145 (63%) of tumors and estrone sulfatase was detected in 93/104 (89%) of tumors. There was no relationship between aromatase activity and tumor size, site, nodal status, menopausal status or estrogen receptor status. There was a significant correlation between the aromatase activity and histological grade, with an excess of aromatase-positive in the high grade tumors (P = 0.03). There was a marginally inverse correlation between the aromatase activity and time to relapse (P < 0.1), a significant correlation between aromatase activity and survival after relapse (P < 0.05) but not with overall survival (P > 0.1). Intratumoral estrone sulfatase activity was not significantly correlated to any putative prognostic factors, nor with time to relapse nor overall survival time.

A fluorimetric enzyme assay for the diagnosis of Sanfilippo disease type D (MPS IIID)

4-Methylumbelliferyl-alpha-N-acetylglucosamine 6-sulphate was synthesized and shown to be a substrate for the lysosomal N-acetylglucosamine-6-sulphate sulphatase (GlcNAc-6S sulphatase). Fibroblasts and leukocytes from 3 different Sanfilippo D patients showed < 1% of mean normal GlcNAc-6S sulphatase activity. The enzymatic liberation of the fluorochrome from 4-methyl-umbelliferyl-alpha-N-acetylglucosamine 6-sulphate requires the sequential action of the GlcNAc-6S sulphatase and alpha-N-acetylglucosaminidase. A normal level of alpha-N-acetylglucosaminidase activity was insufficient to complete the hydrolysis of the reaction intermediate 4-methylumbelliferyl-alpha-N-acetylglucosaminide formed by the GlcNAc-6S sulphatase. A second incubation in the presence of excess alpha-N-acetylglucosaminidase is needed to avoid underestimation of the GlcNAc-6S sulphatase activity.

Studies on the biological activity of triiodothyronine sulfate

Hepatic microsomes and isolated hepatocytes in short term culture desulfate T3 sulfate (T3SO4). We, therefore, wished to determine whether T3SO4 could mimic the action of thyroid hormone in vitro. T3SO4 had no thyromimetic effect on the activity of Ca(2+)-ATPase in human erythrocyte membranes at doses up to 10,000 times the maximally effective dose of T3 (10(-10) mol/L). In GH4C1 pituitary cells, T3SO4 failed to displace [125I]T3 from nuclear receptors in intact cells or soluble preparations. Thus, T3SO4 was not directly thyromimetic in either an isolated human membrane system or a pituitary cell system in which nuclear receptor occupancy correlates with GH synthesis. Thyroid hormones inhibit [3H]glycosaminoglycan synthesis by cultured human dermal fibroblasts, and T3SO4 displayed about 0.5% the activity of T3 at 72 h. Human fibroblasts contained roughly the same level of microsomal p-nitrophenyl sulfatase activity as that previously observed in hepatic microsomes. Propylthiouracil (50 mumol/L) did not affect the action of T3SO4, suggesting that deiodination was not important for this activity of T3SO4. Thus, it appears T3SO4 has no intrinsic biological activity, but, under certain circumstances, may be reactivated by desulfation.