Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.6.1 (sulfatase)
 3,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Phospholipase D preferentially contained in human eosinophil polymorphonuclear leukocytes as compared to other leukocytes was isolated by sequential asion and cation exchange chromatography and gel filtration. The purified eosinophil enzyme specifically liberated choline from I-alpha-phosphatidyl choline with a pH optimum of 4.5-6.0 and exhibited a pI of 5.8-6.2 on polyacrylamide-gel isoelectric focusing, which are properties shared by phospholipase D from plant sources; however, its apparent mol wt of 60,000 is approximately one-half that of the plant enzymes. Eosinophil and cabbage phospholipase D inactivated a partially purified rat platelet-activating factor (PAF) in a time- and dose-dependent reaction. The cleavage of this PAF activity was attributed to the inherent phospholipase D activity of the eosinophil enzyme since the two activities chromatographed together at each purification step, and there was apparent reciprocal inhibition of choline-generating activity by PAF and of PAF-inactivating activity by phosphatidyl choline. Thus, possible regulatory functions of the eosinophil in immediate hypersensitivity reactions include inactivation of a PAF by phospholipase D as well as degradation of slow-reacting substance of anaphylaxis by arylsulfatase B.
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PMID:Isolation of human eosinophil phospholipase D. 0 68

Slow reacting substance of anaphylaxis (SRS-A) was released from human lung passively sensitized with ragweed antibody and challenged with specific antigen E. After purification by ethanol extraction, incubation with alkali (0.1 M NaOH for 30 min at 37 degrees C) and chromatography on silicic acid and DEAE-cellulose, human SRS-A was separated into four biologically active fractions (Fractions I to IV). Arylsulfatase (Type H-1) in 0.1 M sodium acetate buffer, pH 4.5, destroyed the biologic activity of only Fraction I. All four fractions, like SO4=, inhibited the arylsulfatase activity at pH 4.5 but not at pH 6.0 when p-nitrocatechol sulfate was used as substrate. These results suggest that SRS-A contain a sulfur group and that human STS-A, like the prostaglandins, may be a family of compounds. The instability of the purified SRS-A to storage remains a major barrier to their further purification and chemical identification.
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PMID:Separation of slow reacting substance of anaphylaxis (SRS-A) from human lung into four biologically active fractions. 0 68

The availability of a patient with basophilic leukemia manifesting 75 to 90% mature basophils permitted the use of a cell concentration sufficient to generate and release mediators upon interaction with a calcium ionophore in quantities adequate for their physiocochemical characterization. The mediators were defined in terms of their physicochemical characteristics: slow reacting substance of anaphylaxis (SRS-A) by purification through silicic acid chromatography and inactivation by arylsulfatase; eosinophil chemotactic factor of anaphylaxis (ECF-A) by its gel filtration through Sephadex G-25 and inactivation by subtilisin and not trypsin; and platelet-activating factor (PAF) by its inherent binding to albumin. Both ECF-A and histamine were present in their preformed state, and for histamine it was possible to establish that the concentration per cell was comparable to that of normal human basophils. Dibutyryl cyclic AMP suppressed release of histamine and SRS-A, indicating that their availability was under a control similar to that observed with normal cells subjected to immunologic activation. The demonstration that a suspension of leukemic human basophils contained the preformed mediators, histamine and ECF-A, and generated SRS-A and PAF for release along with histamine and ECF-A, after activation with a calcium ionophore, establishes that a single cell type can serve as a source of the four recognized mediators of immediate-type hypersensitivity.
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PMID:The release of four mediators of immediate hypersensitivity from human leukemic basophils. 4 47

The ability of the calcium ionophore A23187 to release slow reacting substance of anaphylaxis (SRA-A) from human leukocytes was studied. About 25 times more SRS-A activity was released from aliquots of leukocytes by ionophore stimulation than by antigen stimulation, although comparable amounts of histamine were released. Cell separation studies revealed that granulocytes other than basophils were also capable of releasing SRS-A. The contractile activity released after challenge with ionophore appeared physicochemically identical to the SRS-A of rat or human origin released by antigen challenge in terms of its stability to base hydrolysis, inactivation by arylsulfatase, and chromatographic behavior on silicic acid and Sephadex LH-20 columns. We suggest that some mediators of allergic reactions previously associated, in man, only with antigen-IgE antibody interaction on mast cells or basophils may be released by other stimuli and from other cell types.
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PMID:Release of slow reacting substance of anaphylaxis (SRS-A) from human leukocytes by the calcium ionophore A23187. 5 45

The net percentage of release of arylsulfatase activity from purified rat mast cells induced by rabbit anti-rat F(ab')2 was consistently only about 1/3 that of histamine. Isoelectric focusing of the released and residual arylsulfatase activities demonstrated specific release of the A type without B and a net percentage of immunologic release of arylsulfatase A equivalent to that of histamine. When the net percentage of histamine and arylsulfatase A release were nearly maximal (88 and 76%) in response to the calcium ionophore A23187, specific release of arylsulfatase B did not occur. Thus, arylsulfatase A and not B was associated with the secretory granule released from the rat mast cell by reversed anaphylaxis or the calcium ionophore. In contrast, subcellular fractionation of water-lysed mast cells yielded arylsulfatase B with the heparin- and chymase-containing granule fraction and arylsulfatase A in the aqueous fraction comprised of cell sap and granule water eluate. It may be that arylsulfatase B resides in a minor second granule, whereas arylsulfatase A is loosely associated with the predominant secretory granule of the rat mast cell.
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PMID:Release of arylsulfatase A but not B from rat mast cells by noncytolytic secretory stimuli. 8 Dec 31

An eosinophil chemotactic factor of anaphylaxis (ECF-A), released along with other chemical mediators of immediate hypersensitivity from sensitized mast cells that have been challenged with specific antigen, is capable of selectively attracting eosinophils. The rate and magnitude of tissue eosinophil influx may be enhanced by ascorbate and inhibited by the neutrophil immobilizing factor (NIF). Eosinophils may then exercise a local regulatory function. Phagocytosis or the action of ECF-A at high concentrations causes eosinophils to release arylsulfatase, which inactivates slow reacting substance of anaphylaxis (SRS-A). Additional possible functions of eosinophils may follow from their content of factors that inhibit histamine release or its mediator function, and the high levels of intracellular plasminogen and phospholipase B. Thus, the unique enzymes and factors released from eosinophils may form the basis of their role in immediate and subacute hypersensitivity reactions.
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PMID:Eosinophil polymorphonuclear leukocyte function in immediate hypersensitivity. 23 19

Arylsulfatase preferentially present in the human eosinophil as compared to other leukocytes was isolated by sequential gel filtration and cation exchange chromatography. The apparent molecular weight of 60,000, the preferential cleavage of 4-nitrocatechol sulfate (PNCS) over p-acetyl-benzenesulfonic acid (PABS), inhibition by phosphate ions and pH optimum of 5.7 are characteristics of a type II B arylsulfatase. Eosinophil arylsulfatase inactivated purified human slow reacting substance of anaphylaxis (SRS-A) in a time-dependent reaction with the rate dependent upon the enzyme/substrate ratio. That SRS-A inactivation was the result of intrinsic arylsulfatase activity was indicated by association of PNCS cleavage and SRS-A inactivating activity during chromatography, the similar pH optimum for cleavage of both substrates and the capacity of SRS-A to inhibit PNCS cleavage by arylsulfatase. The finding that eosinophil arylsulfatase inactivates SRS-A suggests that eosinophil ingress into the site of an immediate hypersensitivity reaction in response to ECF-A could represent a regulatory function.
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PMID:Inactivation of slow reacting substance of anaphylaxis by human eosinophil arylsulfatase. 23 89

The contractile effects of partially purified slow-reacting substance of anaphylaxis (SRS-A) and histamine were compared on isolated guinea pig tracheal spirals and parenchymal strips. Histamine was equally active on both isolated tissues in a concentration-related fashion. SRS-A (0.1--10.0 U/ml) produced a concentration-related effect on parenchymal strips, whereas the tracheal spiral was 100 times less sensitive to this mediator. The contractile activity of SRS-A on parenchymal strips was diminished by incubation with limpet arylsulfatase and antagonized by FPL 55712, a known SRS-A antagonist. SRS-A, further purified by high pressure liquid chromatography, also demonstrated this preferential activity on guinea pig parenchymal strips. These data are consistent with the hypothesis, based on previous in vivo observations, that SRS-A is a selective peripheral airway constrictor.
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PMID:Differential effects of a partially purified preparation of slow-reacting substance of anaphylaxis on guinea pig tracheal spirals and parenchymal strips. 76 39

Eosinophil migration toward a concentration gradient of a chemotactic factor is regulated at four levels. Diverse immunologic pathways generate stimuli with eosinophil chemotactic activity, including the complement products C5a and a fragment of C3a and the peptide products of mast cells and basophils activated by IgE-mediated reactions, such as eosinophil chemotactic factor of anaphylaxis (ECF-A) and other oligopeptides. The intrinsic preferential leukocyte activity of the chemotactic stimuli represents the second level of modulation, with ECF-A and other mast cell-derived peptides exhibiting the most selective action on eosinophils. The third level of control of eosinophil chemotaxis is composed of inactivators and inhibitors of chemotactic stimuli and is exemplified by degradation of C5a by anaphylatoxin inactivator or chemotactic factor inactivator and of ECF-A by carboxypeptidase-A or aminopeptidases. The activity of ECF-A is uniquely suppressed by equimolar quantities of its NH2- terminal tripeptide substituent, presumably by eosinophil membrane receptor competition. Factors comprising the fourth level of regulation, which alter eosinophil responsiveness to chemotactic stimuli, include the chemotactic factors themselves, through deactivation; nonchemotactic inhibitors such as the COOH-terminal tripeptide substituent of ECF-A, the neutrophil-immobilizing factor (NIF), the phagocytosis-enhancing factor Thr-Lys-Pro-Arg, and histamine at concentrations greater than 400 ng/ml; and nonchemotactic enhancing principles represented by ascorbate and by histamine at concentrations of 30 ng/ml or less. Local concentrations of eosinophils called to and immobilized at the site of a hypersenitivity reaction may express their regulatory functions by degrading the chemical mediators elaborated including histamine, slow-reacting substance of anaphylaxis (SRS-A), and platelet-activating factor (PAF) by way of their content of histaminase, arylsulfatase B, and phospholipase D, respectively. Immunologic pathways may thus provide the capability for early and specific host defense reactions with a later influx of eosinophils preventing irreversible local tissue alterations or distant organ effects.
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PMID:Modulation of human eosinophil polymorphonuclear leukocyte migration and function. 79 10

Extracts of isolated rat peritoneal mast cells were demonstrated to contain appreciable quantities of arysulfatase activity. The enzyme was inhibited by both phosphate and sulfate ions and demonstrated a pH optimum of 5.0. The enzyme was recovered in the eluate of DE-52 columns and appeared to have a m.w. of 150,000 of Sephadex G-200 gel filtration. These findings and the anomalous kinetic behavior of the enzyme suggest that at least part of the enzymatic activity is of the arylsulfatase IIA type. While spontaneous release of the enzyme was observed, challenge of isolated rat mast cells with a goat anti-rat IgE serum resulted in a significant increase in release of the enzyme. The arylsulfatase activity extracted from isolated rat mast cells demonstrated comparable activity in inactivating slow reacting substance of anaphylaxis (SRS-A) to that described for human eosinophil and lung arylsulfatase.
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PMID:Functional characterization of rat mast cell arylsulfatase activity. 99 97


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