Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.5.1.4 (deaminase)
 5,113 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A method was elaborated for obtaining polyacrylamide gel zymograms of the cobalt-activated acylase after electrophoresis. Two fractions of the acylase showing activity towards N-chloroacetyl-gamma-L-glutamyl-beta-naphthylamide were found in human kidney, liver and intestine. The two fractions isolated from liver differ in substrate specificity, heat resistance, response to metal ions, inhibition by deaminated dipeptides, and in molecular weight. They differ also from other N-acylamino acid amidohydrolases: aminoacylase (EC 3.5.1.14) and aspartoacylase (EC 3.5.1.15).
 ...
PMID:Polymorphism of the cobalt-activated acylase in human tissues. 2 51

Marked activity of cobalt-activated acylase was found in the sera of 33 of 37 patients with acute toxic hepatitis due to poisoning with either amanita mushrooms or chemicals. The activity of the enzyme showed a positive correlation with that of serum transaminases, reached the highest levels on the patient's admission to hospital and within a few days fell rapidly to undetectable levels. Slight acylase activity was observed in the majority of patients intoxicated with drugs or carbon monoxide but was not seen in sera of those poisoned with non-amanita mushrooms who showed no signs of liver injury. Unlike acylase, the serum activity of gamma-glutamyl transpeptidase remained unchanged over the first days of acute toxic hepatitis. The determination of serum cobalt-activated acylase might be of value in the diagnosis of acute liver injury.
 ...
PMID:Serum cobalt-activated acylase and gamma-glutamyl transpeptidase activities in toxic hepatitis. 24 82

A simple colorimetric method for the assay of cobalt-activated acylase activity in human serum using new and less toxic N-chloroacetyl-gamma-L-glutamyl-p-aminobenzoic acid as substrate has been described. The values obtained with this method are almost the same as with the previously described method using naphthylamide substrate.
 ...
PMID:Acyl derivatives of p-aminobenzoic acid as new substrates for the assay of serum acylase activity. 30 33

Cobalt-activated acylase was isolated from human uterine muscle and myoma. The enzyme was purified by ammonium sulphate precipitation, and subsequent chromatography on DEAE-cellulose, Sephadex G-150 and DEAE-Sephadex. The comparison of muscle acylase and acylase obtained from myoma has shown differences in the enzyme stability, the dependence of activity on pH and in the susceptibility to the effect of activators and inhibitors. Only one molecular form of cobalt-activated acylase has been found in both tissues.
 ...
PMID:Cobalt-activated acylase from human uterine myoma. 43 57

Two molecular forms of cobalt-activated acylase present in human tissues and one or three in sera of patients with viral hepatitis were noted. They have different substrate specificity. Only form 2 is strongly inhibited by alpha-hydroxyisocaproyl-tyrosine and -phenylalanine. Electrophoretic migrations of all enzyme forms are different from those of aminoacylase. Immunoglobulin antiform 2 of the acylase does not precipitate other forms of cobalt-activated acylase or aminoacylase.
 ...
PMID:Molecular forms of cobalt-activated acylase in human tissues and serum of patients with viral hepatitis. 44 40

alpha-Hydroxyisocaproyltyrosine (HyIc-Tyr-OH), a potent competitive inhibitor of the cobalt-activated acylase form 2, was synthesized. Its derivative, alpha-aminopentyl-HyIc-Tyr-OEt was coupled to cyanogen bromide-activated Sepharose 4B and was used for about 100-fold purification of the acylase from human liver by affinity chromatography. The preparation obtained did not show aminoacylase, aspartyl acylase or alanylarylamidase activities. The same chromatographic method was also applied to isolate form 2 of the serum acylase from patients with viral hepatitis and guinea pig placenta.
 ...
PMID:Purification of cobalt-activated acylase by affinity chromatography. 57 48

The activity of cobalt-activated acylase, measured towards N-chloroacetyl- and N-butyryl-gamma-L-glutamyl-beta-naphthylamide, was found in all tissues of the adult animals. In the kidney, liver and small intestine of adult guinea-pig and rat two fractions differing in electrophoretic mobility (fractions 1 and 2) were present. The early foetus contained fraction 2, sometimes accompanied by fraction 3 which later disappeared; on further development of the foetus, fraction 1 appeared. Fraction 1 was distinctly activated by cobalt ions; fractions 2 and 3 were strongly inhibited by deaminated leucylphenylalanine. In the guinea-pig, the molecular weight of the three fractions ranged from 43000 to 59000.
 ...
PMID:Activity and polymorphism of the cobalt-activated acylase in tissues of rodents during development. 66 76

Iproniazid (1-isonicotinoyl-2-isopropylhydrazine), an antidepressant drug removed from clinical use because of hepatic injury, and isopropylhydrazine, a metabolite of iproniazid, were found to be potent hepatotoxins in rats. This animal model was used in studies in vivo and in vitro to define better the biochemical and chemical mechanism(s) by which iproniazid and isopropylhydrazine mediate hepatotoxicity. Phenobarbital, an inducer of a class of hepatic microsomal cytochrome P-450 enzymes, greatly potentiated the necrosis, whereas inhibitors of these microsomal enzymes such as cobalt chloride, piperonyl butoxide and alpha-naphthylisothiocyanate, prevented the necrosis. Bis-para-nitrophenyl phosphate, an inhibitor of esterase and amidase enzymes, prevented the necrosis caused by iproniazid but had no effect on the necrosis caused by isopropylhydrazine. Iproniazid and isopropylhydrazine labeled with tritium or carbon-14 in the isopropyl group were found to bind covalently to hepatic tissue macromolecules, and those pretreatments that increased hepatic necrosis significantly increased covalent binding, whereas those pretreatments which prevented necrosis significantly decreased covalent binding. Iproniazid labeled with tritium in the pyridine ring or carbon-14 in the carbonyl group did not bind significantly to hepatic tissue. Rats that were given iproniazid or isopropylhydrazine, labeled specifically with tritium and carbon-14 on the c-2 methine position of the isopropyl group, expired acetone and carbon dioxide labeled with carbon-14. More importantly, propane was expired and contained a ratio of 3H/14C that was identical to that in the administered iproniazid or isopropylhydrazine and also identical to the 3H/14C ratio of the metabolite that was covalently bound to hepatic tissue macromolecules. Experiments carried out with rat liver microsomes and isopropylhydrazine specifically labeled with deuterium, tritium and carbon-14 support the view that isopropylhydrazine is the metabolite of iproniazid that is oxidized by a microsomal P-450 enzyme to a species that alkylates tissue macromolecules. Some of the urinary metabolites excreted by rats that were administered hepatotoxic doses of iproniazid and isopropylhydrazine have been identified by cochromatography and isotope dilution with synthetic standards and by comparative mass spectra. Compounds excreted into the urine of rats dosed with iproniazid include iproniazid, iproniazid-1-oxide, isonicotinic acid, isonicotinoyl glycine, acetylisoniazid, isopropylhydrazine, 1-acetyl-2-isopropylhydrazine and acetone. Isopropylhydrazine, 1-acetyl-2-isopropylhydrazine, and acetone have been found in the urine of animals administered toxic doses of isopropylhydrazine.
 ...
PMID:Hepatotoxicity and metabolism of iproniazid and isopropylhydrazine. 70 22

Newly synthesized and non-toxic acyl derivatives of p-aminobenzoic acid were used as substrates indiagnostic kit for assay of cobalt-activated acylase activity. The enzyme activity, in serum of patients with viral hepatitis, depends on time, type and treatment of the disease and also on age and sex of patients. The presence of HBs antigen has no influence on it. In the patient sera 1-3 molecular forms of the enzyme were found but in the liver of healthy or sick individuals two forms were noted. Using alpha-hydroxy-isocaproyl-tyrosine covalently coupled to Sepharose 4B as a bioadsorbent; the form 2 of acylase from human liver was isolated and separated from the form 1, aminoacylase and aspartyl acylase. Specific immunoglobulins anti-form 2 does not react with other forms of the enzyme either in serum or in the liver.
 ...
PMID:Cobalt-activated acylase in serum of patients with viral hepatitis. 74 9

The method of measuring enzyme deactivation by monitoring necessary addition of fresh enzyme to keep a constant degree of conversion in a CSTR at constant [E] x tau, the product of concentration of active enzyme [E] and residence time tau, was successfully applied to acylase I from porcine kidney and Aspergillus oryzae fungus. Fungal enzyme was found to be more stable than kidney enzyme. Activation by both Co2+ and Zn2+ ions also yielded increased operational enzyme stability: Co2+ and Zn2+ are better stabilizers than activators. Mg2+ and Ca2+ are found to be neither activators nor stabilizers. Fungal acylase partially deactivated by exposition to a metal-free medium in the CSTR was reactivated by addition of Zn2+, demonstrating that loss of Zn2+ from the enzyme molecule is mainly responsible for deactivation in a continuous reactor.
 ...
PMID:Operational stability of enzymes. Acylase-catalyzed resolution of N-acetyl amino acids to enantiomerically pure L-amino acids. 147 69


1 2 3 4 5 6 7 Next >>