ABSTRACT
The authors studied the effect of cationic surfactants (CS), such as alkyl(C8H17-C18H37)dimethylbenzylammonium (I), alkyl(C8H17-C16H33)benzyltrimethylammonium (II), alkyl(C8H17-C16H33)di-beta-hydroxyethylbenzylammonium (III) chlorides and chlorhydrate of glycine decyl ester (IV) on the ATPase activity of E. coli 1257 cell, spheroplasts, and isolated membranes. Changes in the ATPase activity of the E. coli cells and spheroplasts were found to depends on the concentration and the structure of the cationic surfactants. The removal of the cell wall increased the destroying effect of CS on the cytoplasmic membranes and enhanced the ATPase inhibition. The compounds with 16 and 18 carbon atom radical had the highest inhibitory effect. The action of cationic surfactants on the membrane is accompanied by changes in the protein and phospholipid composition and by significant solubilization of ATPase with pronounced inactivation of the enzyme. The kinetics of inhibition of E. coli membrane ATPase was studied to the presence of the homological series I and IV. The cationic surfactants under study inhibited the ATP hydrolysis catalysed by E. coli ATPase by a mixed type mechanism. Ki = 58.21.10(-4) M for IC10H21; 10.67.10(-4) M for IC12H25; 0.58.10(-4) M for IC16H33; 0.16.10(-4) M for IC18H37, and 5.93.10(-4) M for IV.
Subject(s)
Adenosine Triphosphatases/antagonists & inhibitors , Anti-Bacterial Agents , Escherichia coli/enzymology , Surface-Active Agents/pharmacology , Cations/pharmacology , Chemical Phenomena , Chemistry , Escherichia coli/drug effects , Hydrolysis , KineticsABSTRACT
The character of the growth of Escherichia culture after treatment with alkyl dimethylbenzyl ammonium chloride (a cation surface-active substance) has been studied. The action of the preparation at bacteriostatic concentrations is reversible and manifested only by the increased duration of the lag phase. The complete restoration of the processes ensuring the growth and mitosis of the cells usually occurs. The preparation causes disturbances in the permeability barrier of the cell membranes, appearing immediately on contact with cation surface-active substances. This compound affects the cytoplasmic membranes of Escherichia cells at extremely low concentrations (0.0001-0.0002%); as a result, the leakage of low-molecular substances from the cells occurs. These disturbances in permeability are not accompanied by the disappearance of nucleic acids from the cells. The preparation used at bactericidal and subbactericidal concentrations denatures high-molecular cell components to a variable degree. The study of the ultrastructure of cells and spheroblasts shows that alkyl dimethyl-benzyl ammonium chloride destroys the structure of the outer and cytoplasmic membranes, as well as the ribosomal apparatus of Escherichia cells.
Subject(s)
Escherichia coli/drug effects , Quaternary Ammonium Compounds/pharmacology , Spheroplasts/drug effects , Surface-Active Agents/pharmacology , Adenosine Triphosphatases/metabolism , Cell Membrane Permeability/drug effects , Dose-Response Relationship, Drug , Escherichia coli/enzymology , Escherichia coli/ultrastructure , Microscopy, Electron , Spheroplasts/enzymology , Spheroplasts/ultrastructureABSTRACT
An immune response to urate oxidase--an enzyme from pig liver was studied. Peculiarities of antibody formation were investigated in three animal species. It was shown that the scheme for repeated injections of the enzyme preparation had a marked effect on the intensity of humoral immune response. In studying the process of the enzyme allergic properties it was found that urate oxidase had anaphylactogenic and skin sensitizing properties. The strength of anaphylactic reaction depened on the sensitizing dose of the antigen and correlated with the results of active skin anaphylaxis. However, there was no correlation between the strength of the immune response determined by means of the indirect hemagglutination test and the intensity of anaphylactic reaction.
Subject(s)
Liver/enzymology , Urate Oxidase/immunology , Allergens , Anaphylaxis/etiology , Animals , Antibody Formation , Antigens , Chinchilla , Dose-Response Relationship, Immunologic , Guinea Pigs , Hypersensitivity/etiology , Mice , Mice, Inbred BALB C , Rabbits , Skin/immunology , Swine , Urate Oxidase/administration & dosageABSTRACT
A highly purified uratoxidase was isolated from the pig liver. The sedimentation coefficient of the enzyme was 6.96 S and the molecular weight was 122,000 +/- 4,000. The enzyme was a tetramer consisting of subunits with a molecular weight of 31,600 +/- 2,500. Uratoxidase showed high substrate specificity with 0.05 M borate buffer, pH 8.5. During competitive inhibition 8-azaxanthine (Ki = 3.1 X 10(-7) M) produced the strongest inhibitory effect as compared with other purine compounds. N-chloromercuric benzoate and ascorbic acid also inhibited strongly uratoxidase activity. EDTA-Na2, methyl ester of n-oxybenzoic acid, phenyl methyl sulphonyl fluoride and cystein did not influence the enzyme activity.