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Z Porembska

Publications and source records attributed to Z Porembska.

At least 37 records · Page 2Linked to original sources
PubMed1983

Purification of rat kidney arginases A1 and A4 and their subcellular distribution.

Arginase A1 and arginase A4 were isolated from rat kidney. Arginase A4, which is the main form of arginase in rat kidney, was obtained at a highly purified preparation; its specific activity was 1057 mumoles ornithine . min-1 . mg-1 protein. The two forms differed in subcellular localization. Form A1 was restricted to the cytosol while form A4 occurred mainly in the mitochondrial matrix. Kidney arginases A1 and A4 were found to differ in immunological properties. Kidney arginase A1, in contrast to arginase A4, precipitated with antibodies against arginase A1 from rat liver. Arginase A1 from kidney was shown to differ from arginase A1 from the liver. The two enzymes could be distinguished by double diffusion test and immunoelectrophoresis.

Animals↗
PubMed1983

Hybridization of subunits of rat liver arginase A1 and rat kidney arginase A4.

Recombination of subunits of rat liver arginase A1 and rat kidney arginase A4 yielded a product which in polyacrylamide gel electrophoresis and DEAE-cellulose chromatography separated into five proteins with arginase activity. Proteins I and V corresponded in polyacrylamide gel-electrophoresis, DEAE-cellulose chromatography and immunological properties to the parental forms A1 and A4, respectively. Formation of five arginase hybrids proved the tetrameric structure of native arginases.

Animals↗
PubMed1980

Purification and some properties of human heart arginase.

Arginase from extracts of human heart was purified about 1500-fold. In polyacrylamide-gel electrophoresis the enzyme migrated to the cathode at pH 5.5, showing very low mobility at pH 8.9. Molecular weight determined by gel filtration was 120 000. The Km for L-arginine was 5 mM. L-Ornithine and L-lysine were competitive inhibitors. The enzyme was completely inactivated by treatment with EDTA, and dissociated into subunits with mol.wt. of about 30 000. Addition of Mn2+ ions to the inactive subunits resulted in reappearance of the enzyme activity; the molecular weight of the reactivated enzyme corresponded to that of the native form.

Amino Acids↗
PubMed1980

Subcellular localization of arginase in rat liver.

Rat liver arginase is a cytoplasmic enzyme but it is bound to the surface of cellular structures separated in isotonic sucrose medium depleted of ions; this association is prevented by KCl. The purified preparations of undamaged nuclei contain practically no arginase activity.

Animals↗
PubMed1977

Reactivation of the EDTA-treated arginase from rat and calf liver.

1. The anionic calf liver arginase, like the cationic rat liver enzyme, is inactivated by EDTA-treatment. The activity is fully restored by Mn2+. A smaller effect is observed with Cd2+, Ni2+ and Co2+. 2. The EDTA-inactivated calf liver arginase, unlike the rat liver enzyme, does not dissociate into subunits, and its mol.wt. (120 000) is unchanged. 3. The reactivation of rat liver arginase subunits (mol.wt. 30 000) by Ni2+ is accompanied, similarly as in the case of Mn2+, by reassociation to the form of mol.wt. 120 000, i.e. the same as for the native enzyme. 4. It is suggested that Mn2+ in arginase is bound at the active site and at the site responsible for maintenance of the oligomeric structure. In calf liver enzyme this binding site is inaccessible to the chelating agent.

Animals↗
PubMed1976

Oligomeric structure of A1 arginase from rat liver and A4 from kidney. Difference in charge of subunits.

1. The predominant form of rat liver arginase, A1, and that of kidney, A4, were isolated and partially purified. 2. It was found that arginase A4, similarly as A1, has oligomeric structure. Either of the enzymes on EDTA treatment dissociates into inactive subunits of molecular weight 30 000 daltons. Addition of Mn2+ ions restores the activity and causes reassociation of subunits to the native form of 120 000 mol. wt. 3. The subunits of A4 differ considerably in electrophoretic mobility from subunits of A4, which probably is the reason why the native forms of the enzyme from kidney and liver differ in electrophoretic behaviour.

Animals↗
PubMed1975

Early diagnosis of myocardial infarction by arginase activity determination.

In blood serum of healthy persons the activity of arginase (EC 3.5.3.1) is very low, whereas in patients with myocardial infarction it increases within a few hours after the first attack of coronary pain, and returns to normal values after 3-5 days. No increase of arginase activity was observed in sera of patients with angina pectoris, coronary insufficiency or cardiac failure. Determination of arginase activity in blood serum may serve as a useful test in early differential diagnosis of myocardial infarction.

Angina Pectoris↗
PubMed1975

Purification and some properties of arginase from human lung.

Arginase from human lung has been isolated and purified about 100-fold. During the purification procedure the enzyme was stabilized by Mn2+. The molecular weight determined by Sephadex G-150 gel filtration was found to be 120 000. The enzyme is highly specific towards L-arginine. Incubation of the enzyme with EDTA for 60 min at pH 7.5 and 37 degrees C results in dissociation into inactive subunits of mol. wt. 30 000. On addition of Mn2+ ion to the inactivated enzyme, the subunits reassociate into the native form of the enzyme of mol. wt. 120 000, and the activity is restored.

Adult↗