Search PubMed⌕ Search

Biomedical subjects

E Wolna

Publications and source records attributed to E Wolna.

At least 19 recordsLinked to original sources
PubMed1993

Effect of amino acids on the pig muscle enolase.

Fifteen amino acids were used to investigate their effects on the pig muscle enolase. The basic and hydrophobic amino acids decreased the enzyme activity slightly. In the presence of acidic amino acids such as aspartic and glutamic acid the degree of inhibition was higher. One of the most potent inhibitors was cysteine. The presence of amino acids does not change the affinity to the substrate of enolase 2-phosphoglycerate. The possible physiological influence of amino acids on the function of enolase is discussed.

Amino Acids↗
PubMed1991

Effect of proteases on the activity of enolase from muscle of carp (Cyprinus carpio) and pig.

The treatment of enolase from pig and carp (Cyprinus carpio) with proteases resulted in a decrease of enzymatic activity, which depended on the kind of protease used. The most active were trypsin and subtilisin. Substrate and magnesium ions protected enolase against inactivation. The enolase from pig muscle was much more resistant to protease action than this enzyme from carp muscle. Some differences in the structure between the two enolases are suggested.

Animals↗
PubMed1987

Inactivation of pig muscle enolase by carbohydrate metabolites.

Fourteen carbohydrate metabolites and related compounds were used to investigate the inhibition of enolase from pig muscle. Glucose and fructose decreased the activity very slightly. The degree of inhibition by phosphate derivative was stronger and dependent on the position of phosphate residue. One of the strongest inhibitor was glyceraldehyde-3-phosphate. The presence of inhibitors do not change the affinity to the substrate - 2-phosphoglycerate. The possible physiological role of enolase in carbohydrate metabolism is discussed.

Animals↗
PubMed1987

Chemical modification of histidine, tyrosine, tryptophan and cysteine residues in carp (Cyprinus carpio) muscle enolase.

Enolase from carp (Cyprinus Carpio) muscle was modified by diethylpyrocarbonate, tetranitromethane, N-bromosuccinimide and 5,5'-dithiobis(2-nitrobenzoic acid). The extent and rate of modification and its effect on the enzyme activity were determined. Modification of histidine, tyrosine and tryptophan residues caused complete inactivation of the enzyme; Mg2+ as well as 2-phosphoglycerate markedly altered the rates of modification and inactivation. The above-mentioned amino acid residues seem to be essential for the functioning of muscle enolases. Modification of cysteine residues had no effect on the enolase activity.

Amino Acids↗
PubMed1986

Studies on immunological properties of enolase from carp muscles (Cyprinus carpio) after chemical modification of some amino-acid residues.

After modification of histidine residues, enolase from carp muscles lost the ability to precipitate with antibodies against native enzyme. This ability remained after nitration of tyrosine residues, but the immunoelectrophoretic pattern--localisation and height of arcs--differed from that of native enolase. Minor changes of this pattern were found in enolase with modified tryptophan residues.

Amino Acids↗
PubMed1983

Purification and properties of enolase from carp (Cyprinus carpio). Comparison with enolases from mammals' muscles and yeast.

The enolase (2-phospho-D-glycerate hydrolyase E.C. 4.2.1.11) from carp muscle was obtained, the specific activity--88 U/mg of protein. Km for 2-phosphoglycerate was 0.313 mM and for phosphoenolpyruvate--0.76 mM. The enzyme is active only in the presence of divalent metal ions, Mg2+ being the best activator. The phosphate and fluoride decreased the activity of enzyme. The molecular weight of the dimeric form of enzyme was found to be 93,000. The enzyme is immunologically different from pig muscle enolase.

Animals↗
PubMed1983

Effects of Wratizolin on growth and metabolism of cells in vitro.

The new isothiazole derivative--Wratizolin was found to have several properties which are characteristic of the acidic non-steroidal antiinflammatory drugs, among others--indomethacin. The minimal cytotoxic concentration (MCC) of Wratizolin for the chicken or mouse embryonic monolayer tissue cultures maintained in the media without serum is 6.25 microM. In the medium containing from 3 to 10% calf serum MCC for several animal cells was found to be from 12.5 to 62.5 microM. Wratizolin inhibited the synthesis of DNA in the cultured human lymphocytes at the subtoxic concentration only. Wratizolin, in a characteristic way, stimulates the synthesis of lactic acid and increases the consumption of glucose by the chick or mouse fibroblasts. The drug at concentration of 10(-6) to 10(-12) M stimulates the multiplication of mouse L cells. In all above tests Wratizolin is more active than indomethacin.

Amnion↗
PubMed1980

Inactivation of enolase with tetranitromethane.

1. All 20 tyrosyl residues of enolase from human and pig muscle were nitrated with tetranitromethane in mild conditions; 2-phosphoglycerate and magnesium ions decreased the rate of reaction. 2. Inactivation took place in two steps: (a), nitration of 6 - 10 tyrosine residues of enolase decreased the activity by about 20%, without affecting Km value, molecular weight of pH dependence; (b) on nitration of 12 tyrosyl residues, inactivation was nearly complete, with concomitant profound changes in the enzyme properties. 2-Phosphoglycerate and magnesium ions present together protected significantly against inactivation. 3. The results suggest that the activity of enolase is dependent on intactness of tyrosyl residues.

Animals↗
PubMed1977

The reaction of N-bromosuccinimide with enolase.

Ten tryptophan residues per one protein molecule were found to be present in the enolase from human and swine muscle. In Tris buffer, N-bromosuccinimide (NBS) inactivated the enolases after oxidation of all 10 tryptophan residues. The presence of 2-phosphoglycerate (2-PGA) partially protected the activity, and in the presence of 2-PGA together with Mg2+ full protection was observed. In phosphate buffer, only 6 tryptophan residues could be oxidized, but the enzyme was fully inactivated. 2-PGA made possible the oxidation of all 10 tryptophan residues, concomitant with full inactivation. In either case, Mg2+ had no effect. The Km values and pH optima were the same for the native and partially NBS-modified enolases.

Animals↗