Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:3.4.15.1 (ACE)
18,300 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Angiotensin I-converting enzyme [EC 3.4.15.1] was rapidly and highly purified from a particulate fraction of hog kidney cortex with 13% yield. The procedure, which was rapid, included fractionation on DEAE-cellulose and calcium phosphate gel, chromatographies on DEAE-Sephadex A-50 and hydroxylapatite columns, and gel filtration on a Sephadex G-200 column. The purified enzyme preparation gave two protein bands on standard disc gel electrophoresis, but showed a single protein component on the gel after treatment with neuraminidase [EC 3.2.1.18]. The data strongly suggest that the purified enzyme preparation was a mixture of sialo- and asialo-enzyme. Sialic acid residues apparently do not contribute to the catalytic activity of the enzyme. The enzyme was activated more by chloride ions than by other halide ions tested, using Bz-Gly-Gly-Gly as a substrate. The dissociation constant for chloride ions was determined to be 2.2 mM. Chloride did not protect the enzyme against heat or low pH. The enzyme was resistant to inactivation by trypsin [EC 3.4.21.4] and chymotrypsin [EC 3.4.21.1].
...
PMID:Renal angiotensin I-converting enzyme as a mixture of sialo- and asialo-enzyme, and a rapid purification method. 1 Feb 87

Angiotensin I-converting enzyme (peptidyl dipeptide hydrolase, EC 3.4.15.1) was solubilized from the membrane fraction of human lung using trypsin treatment and purfied using columns of DE 52-cellulose, hydroxyapatite and Sephadex G-200. The purified enzyme was shown to convert angiotensin I to angiotensin II and also to inactivate bradykinin. The specific activity of the enzyme was 9.5 units/mg protein for Hippuryl-His-Leu-OH and 0.665 mumol/min per mg protein for angiotensin I. The enzymic activity obtained after trypsin treatment (1 mg/200 mg protein) for 2 h could be divided into three components: (i) an enzyme of molecular weight 290 000 (peak I), (ii) an enzyme of molecular weight 180 000 (peak II) and (iii) an enzyme of molecular weight 98 000 (peak III), by columns of DE 52-cellulose and Sephadex G-200. Km values of peak I, II and III fraction for Hippuryl-His-Leu-OH were identical at 1.1 mM. pH optimum of the enzyme was 8.3 for Hippuryl-His-Leu-OH.
...
PMID:Purification of angiotensin I-converting enzyme from human lung. 1 71

The anti-inflammatory activity of FL 70, a derivative of 2,5-dihydroxy-benzoic acid, was examined in a number of conventional experimental models. In addition, FL-70 was tested for its inhibitory action on enzymes. The results were as follows: 1. The induction of a local inflammatory reaction and the subsequent i.v. injection of trypan blue showed that FL 70 reduces the capillary permeability. 2, FL-70 significantly suppresses exudation in the formalin-induced peritonitis of the rat. 3. A slight inhibition of an edema in the footpad of the rat induced by formalin-dextran was not shown to be statistically significant. 4. Local swelling could be markedly inhibited in the turpentine-oil induced inflammatory reaction of the rabbit. 5. Exudation and formation of granulomatous tissue was inhibited in Selye's granuloma. 6. FL-70 markedly inhibited the local inflammatory reaction accompanying the cutaneous reaction in experimental vaccinia infection of the rabbit skin. The size of the infiltration after intracutaneous infection of the virus was not reduced. 7. FL-70 could not prevent the onset of clinical signs, if administered in experimental allergic encephalitis. 8. The activity of acid phosphatase was inhibited by FL-70. Alcaline phosphatase, cholinesterase, leucin aminopeptidase, glucose-6- phosphatase-dehydrogenase (G-6-PDH), trypsin and chymotrypsin were unaffe-ted. FL-70 inhibits the following, G-6-PDH activated reduction process: glucose-6-phosphate (see article).
...
PMID:[Anti-inflammatory activity of a new quinoid polyradical (FL-70)]. 16 92

The solubilization of angiotensin I-converting enzyme (peptidyldipeptide hydrolase, EC 3.4.15.1) from rabbit lung was carried out using trypsin treatment. A good recovery of 76% was obtained. The enzyme from solubilized fraction was purified using colums of Sephadex G-200, hydroxyapatite and DEAE-cellulose. The purified enzyme was shown to convert angiotensin I to angiotensin II and also to inactivate bradykinin. The specific activity of the enzyme was 24.3 units/mg protein for hippurylhistidylleucyl hydroxide and 0.182 mumol/min per mg protein for angiotensin I. The enzymic activity obtained after trypsin treatment for 5 h could be divided into two components: (i) an enzyme of molecular weight 300 000 (peak II) and (ii) an enzyme of molecular weight 145 000 (peak III), by Sephadex G-200 gel filtration. The molecular weight of the denatured enzyme was found to be 155 000 by disc gel electrophoresis in the presence of sodium dodecyl sulfate. Km values of peak II and peak III fraction for Hippuryl-His Leu-OH were 2.6 mM.
...
PMID:Solubilization of angiotensin I-coverting enzyme from rabbit lung using trypsin treatment. 18 21

Endothelial cells are a major source of kininase enzymes including kininase II. Kininase II is situated along the plasma membrane, not as an ecto-enzyme but as an enzyme synthesized by the endothelial cells themselves. However, it is likely that endothelial cells do more than degrade kinins. These cells are contractile and may possess kinin receptors; a possibility supported by the fact that kinins stimulate endothelial cells to form and release prostaglandin-related substances. In addition, we have found that endothelial cells in culture are reactive with antibodies to alpha 2-macroglobulin. Endothelial cells can hydrolyze [3H]Pro-Phe-Arg-anilide, a kallikrein substrate, but the reaction is not inhibited by soya bean trypsin inhibitor (SBTI) or Trasylol. Possibly kallikrein or a related trypsin-like enzyme is bound to alpha 2-macroglobulin and is not free to react with the inhibitors. Thus, endothelial cells can bind and inhibit kallikrein-like enzymes, degrade kinins and respond to kinin stimulation.
...
PMID:Endothelial cells and components of the kallikrein-kinin system. 22 4

Purification of angiotensin I-converting enzyme from human lung and characteristics of the enzyme was studied. Experimental pneumonitis was produced in rabbits and the change of the activity of angiotensin I-converting enzyme was studied in purpose to clarify the role of this enzyme in the metabolism of vasoactive peptides in the lung. Purification was performed using trypsin treatment, acid treatment, DE52-cellulose column chromatography, hydroxyapatite chromatography and Sephadex G-200 gel filtration. The enzyme after final step showed a single band on disc gel electrophoresis. Experimental pneumonitis was produced by injection of Complete Freund's adjuvant (acute pneumonitis) and of N-nitroso-N-methylurethane (chronic pneumonitis). In acute experiment, angiotensin I-converting enzyme activity in pulmonary tissue and in plasma was significantly decreased. In perfusion experiment, conversion of angiotensin I to angiotensin II and inactivation of bradykinin were also significantly decreased. In case of decreased activity of angiotensin I-converting enzyme in the lung, less angiotensin II will be released into systemic circulation and bradykinin will pass through the pulmonary circulation into systemic circulation, thus this may result in the decrease of systemic blood pressure.
...
PMID:Purification and properties of angiotensin I-converting enzyme in human lung and its role on the metabolism of vasoactive peptides in pulmonary circulation. 22 10

Angiotensin I(AI)-converting enzyme (ACE) (EC 3.4.15.1) was solubilized from the membrane fraction of chicken lung using trypsin and nonidet P40 extraction, and then purified to homogeneity by captopril affinity chromatography. Comparison of trypsin-extracted and detergent-solubilized membrane-bound converting enzyme by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and isoelectric focusing indicated that the membrane-binding sequence contributed to a large extent to the size and charge of the enzyme. Both forms of the enzyme were glycoproteins but they differed in the glucidic content; 4.5% by weight of the enzyme in the trypsin-extracted ACE and 15% by weight of the enzyme in the detergent-solubilized ACE. In both cases hexoses were the most abundant residues. Both forms of the enzyme were found to contain 1 g-atom zinc/mol enzyme. The purified enzymes did not only split Hip-His-Leu but also AI and bradykinin. The Michaelis constant (Km) and maximum velocity (Vmax) values of the trypsin-extracted ACE for Hip-His-Leu were 52 x 10(-5) mol/l and 15.36 nmol/min respectively, and for AI they were 7.8 x 10(-5) mol/l and 0.45 nmol/min respectively. The Km and Vmax values of the detergent-solubilized ACE for Hip-His-Leu were 32 x 10(-5) mol/l and 11.75 nmol/min respectively, and for AI they were 6.5 x 10(-5) mol/l and 0.97 nmol/min.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Characterization of chicken lung angiotensin I-converting enzyme. 131 47

1. Angiotensin I-converting enzyme (EC 3.4.15.1) has been purified to electrophoretic homogeneity from chicken lung by using a facile two-step protocol which included affinity chromatography on Sepharose-bound captopril. 2. Captopril was a potent inhibitor of chicken lung angiotensin I-converting enzyme with Ki values of 2.0 nmol/l and 1.6 nmol/l for detergent-extracted and trypsin-extracted angiotensin I-converting enzymes, respectively. 3. Molecular weight comparison of trypsin-extracted (M(r)270,000) and detergent-extracted (M(r)690,000) angiotensin I-converting enzyme indicated that membrane-binding sequence contributed to a large extent to the enzyme molecule. 4. Kinetic properties of both forms of the enzyme suggested that the membrane-bound sequence contributed to an increase of the enzyme-substrate affinity.
...
PMID:Inhibition and affinity chromatography of chicken lung angiotensin I-converting enzyme with captopril. 132 42

The pyruvate dehydrogenase complex (PDC) from muscle of the adult parasitic nematode Ascaris suum plays a unique role in its anaerobic mitochondrial metabolism. Resolution of the intact complex in high salt dissociates the pyruvate dehydrogenase subunit but leaves the dihydrolipoyl dehydrogenase subunit (E3) and two other proteins with apparent M(r)s of 45 and 43 kDa bound to the dihydrolipoyl transacetylase (E2) core. These proteins are not observable on Coomassie brilliant blue-stained gels of other eukaryotic PDCs, but the 45-kDa protein is similar in apparent M(r), pI, and sensitivity to trypsin to the Kb subunit of the bovine kidney PDH alpha kinase. Acetylation of the ascarid PDC with [2-14C]pyruvate under conditions designed to maximize the incorporation of label into protein yielded only a single radiolabeled subunit, E2. These results confirm earlier reports that the ascarid PDC lacks protein X, an integral component recently identified in other eukaryotic PDCs. About 1.6 to 1.8 mol of 14C was incorporated/mole of E2, suggesting that the ascarid E2 contained two lipoly-bearing domains. Domain mapping of the 14C-acetylated ascarid E2 by limited tryptic digestion identified two lipoyl-bearing fragments with apparent M(r)s of 50 and 34 kDa and two core fragments with apparent M(r)s of 46 and 30 kDa. The ascarid E2 domain structure appears to be similar to that of other E2s. However, it appears that the subunit-binding domain (E2B) of the ascarid E2 may be significantly larger or be flanked by larger than normal interdomain regions. An enlarged E2B domain may be necessary to accommodate the additional binding of E3 to the E2 subunit in the ascarid complex, in the absence of protein X.
...
PMID:The pyruvate dehydrogenase complex from the parasitic nematode Ascaris suum: novel subunit composition and domain structure of the dihydrolipoyl transacetylase component. 137 97

Porcine heart muscle pyruvate dehydrogenase (PDH, EC 1.2.4.1) with subunit composition alpha 2 beta 2 catalyzes the initial decarboxylation step of an oxidative decarboxylation sequence of pyruvate. Highly purified PDH, was further activated several-fold by limited digestion with trypsin, Staphylococcus aureus V8 proteinase (V8) or papain. The activation with these proteinases required about 10 min to attain a maximal level, lasted 1/2-2 h and thereafter decreased gradually. Addition of an inhibitor of each proteinase resulted in an immediate cessation of any further changes in the enzymatic activity. The optimal pH of the proteinase-activated PDH was not affected. Proteinases increased the maximum velocity and the apparent Km values for pyruvate, but the Hill coefficients for pyruvate were unchanged. Proteinase-activated PDH was capable of associating two other component enzymes to produce large unit resembling the native complex. The Coomassie brilliant blue stained gels after SDS-PAGE showed that the PDH alpha subunit (41 kDa) was cleaved by trypsin or V8 into two major fragments (31 and 10 kDa), whereas PDH beta was unaffected. By amino-terminal sequence analyses of these fragments the trypsin cleavage sites were identified as Arg-273 and Arg-282 and the V8 cleavage sites were Glu-277 and Glu-280.
...
PMID:Proteinase-catalyzed activation of porcine heart muscle pyruvate dehydrogenase and identification of its cleavage site. 173 46


1 2 3 4 5 6 7 8 9 10 Next >>

---