Effect of Ionophores on Activity of Na,Cl(HCO )-ATPase.

We studied the effects of ionophores on activity of Na,Cl(HCO )-ATPase. The most significant effect on the activity of this enzyme was produced by protonophore 2,4-dinitrophenol. The effect of this drug largely depended on the cation and anion composition and pH of the incubation medium and its pH.

Substrate Specificity of Na,Cl(HCO)-ATPase.

We studied substrate specificity of Na,Cl(HCO)-ATPase. In most cases, replacement of ATP for other phosphate-containing substances resulted in not only pronounced suppression of phosphohydrolase reactions, but also dramatic changes of their responsiveness to the stimulating effect of monovalent ions. The data showed that Na,Cl(HCO)-ATPase is a highly specific enzyme for ATP.

Ca²⁺ ions regulate activity of Na⁺ ,Cl⁻(HCO₃ ⁻)-ATPase in the mucosa of rabbit small intestine.

We studied the effects of bivalent metal ions on activity of Na(+),Cl(-)(HCO3 (-))-ATPase was studied. In contrast to Ba(2+), Co(2+), Zn(2+), and Mn(2+) ions, Ca(2+) and Mg(2+) ions in a concentration of 0.25 mM completely inhibited this enzyme.

[A comparative analysis of the antigenic complexes isolated from synthetic and semisynthetic media for the cultivation of Bordetella pertussis].

Some physicochemical properties of B.pertussis antigenic complexes isolated from synthetic and semisynthetic culture media have been studied. The chemical composition of these complexes has been determined.

[Isolation and identification of an antibiotic from culture 8-86].

An antibiotic complex was isolated from culture 8-86 referred to Bacillus. The complex consisted of components 8-86A and 8-86B active against gram-negative organisms. By its physico-chemical properties such as IR and UV spectra, amino acid composition, specific rotation and fatty acid composition component 8-86B was shown to be close to polymyxin F.