ABSTRACT
The inhibition effect of ionic lead on membrane ATPase activity, transmembrane potential (delta psi) and permeability level of the Pb-sensitive P. fluorescens B894 and Pb-resistant P. fluorescens B4252 bacteria cells have been studied. It have been shown that decreasing ATPase activity and transmembrane potential values and the increasing of permeability by lead are higher for Pb-sensitive strain then for Pb-resistant. It is suggested that mechanism of the ionic lead toxic effect deals with plasma membrane biochemical parameters (ATPase activity, value of delta psi) alterations and interruption of it barrier function.
Subject(s)
Lead/pharmacology , Pseudomonas fluorescens/drug effects , Adenosine Triphosphatases/antagonists & inhibitors , Cations , Cell Membrane/drug effects , Cell Membrane/enzymology , Lead/chemistry , Membrane Potentials/drug effects , Pseudomonas fluorescens/enzymologyABSTRACT
The possibility of increasing resistance of some Pseudomonas strains to cobalt at adaptation to monotonous increasing its concentration was studied. Strains Pseudomonas fluorescens B5242 and Pseudomonas fluorescens B894 are capable to increase its resistance in such conditions via inducible synthesis of protective surface proteins. The molecular masses of such proteins were 55.0; 45.0 and 33.0 kDa for P. fluorescens B5242 strain.
Subject(s)
Adaptation, Physiological , Bacterial Proteins/isolation & purification , Cobalt/pharmacology , Membrane Proteins/isolation & purification , Pseudomonas fluorescens/physiology , Bacterial Proteins/biosynthesis , Bacterial Proteins/chemistry , Membrane Proteins/biosynthesis , Membrane Proteins/chemistry , Molecular Weight , Pseudomonas fluorescens/drug effects , Pseudomonas fluorescens/metabolismABSTRACT
Effect of thallium (TlNO3) on the ATPase activity and transmembrane potential (Dj) of bacteria with different levels of resistance to this metal has been studied. The hypothesis has been made that the resistance biochemical mechanism is based on the energy transformation systems in the cell.
Subject(s)
Adenosine Triphosphatases/metabolism , Alcaligenes/drug effects , Membrane Potentials/drug effects , Thallium/pharmacology , Alcaligenes/enzymology , Alcaligenes/physiology , Species SpecificityABSTRACT
Effect of heavy metals (gold, zinc and cadmium) on the ATPase activity and transmembrane potential (delta psi) as integral index of bacterial cells membrane processes intensity has been studied. It was shown that studied membrane systems of bacteria are very sensitive to the action of heavy metals and they can serve as indicators of resistance of bacterial cultures.
Subject(s)
Adenosine Triphosphatases/drug effects , Alcaligenes/drug effects , Bacillus cereus/drug effects , Metals, Heavy/toxicity , Cadmium/toxicity , Cell Membrane/drug effects , Gold/toxicity , Membrane Potentials/drug effects , Zinc/toxicityABSTRACT
Sensitivity of membrane ATPase to heavy metals was studied in bacterial stains Bacillus cereus ATCC 14579, Bacillus cereus B4368, and Alcaligenes eutrophus CH34 was studied. The inhibition effects of metals on membrane ATPase ranged in the same order (Au > Cu > Zn > Co > Mn) as their effects on the growth of cultures. It is suggested that membrane ATPase is one of the targets for the action of heavy metal ions within the microbial cell and, therefore, its activity may serve as an indicator of their toxicity.
