[Obtaining of bacterial bioluminescent strain Protobacterium phosphoreum B7071 (lux+) for the determination of zinc ion concentration].

The transconjugate containing hybrid plasmid (Te(R)Zn(R)lux+) was obtained using the conjugation method on Pseudomonasfragi T2(5) (Te(R)ZnR) strain and bioluminescent strain Protobacterium phosphoreum B7071 (lux+). The expression regulation of lux-genes on the obtained plasmid is carried out by promotor-operational area conjointly with zinc resistance genes. The cells of the obtained genetically modified bacteria have the ability to specific induced luminescence, which is a respond to zinc ions' presence in the measuring medium. It was shown that the cells' bioluminescence intensity of trans-conjugate is linearly dependent on zinc ions' concentration within the range of 1-100 microM, that provides the opportunity of using biosensor as a strain for qualitative and quantitative detection of the metal. The low sensitivity limit of this method is 0.5 microM for the metal. Besides having high sensitivity, the developed lux-biosensor is highly specified.

[Effect of colloid gold on physiologic-biochemical processes in Escherichia coli 1257]. / Vliianie kolloidnogo zolota na fiziologo-biokhimicheskie protsessy Escherichia coli 1257.

The influence of colloid gold on the growth processes, ATP-ase activity and extrusion of protons in Escherichia coli 1257 was studied. The particles of colloid gold exert nonmonotonous influence on these processes with different direction is such a way that small concentration of this metal (5 x 10(-7)-5 x 10(-6) mg/ml) exert stimulative effect, while higher concentrations of colloid gold result in the suppression of biological activity of the bacterial cells. The discovered peculiarities of colloid gold influence of E. coli strain may be determined by specificity of contact interaction of metal particles with the surface of bacterial cells.

[Obtaining bioluminescent bacterial strains for detection of thallium ions]. / Poluchenie bioliuminestsentnykh shtammov bakterii dlia detektsii ionov talliia.

The possibility of Alcaligenes eutrophus T1 luxphenotype creation by temperature induced mutagenesis has been shown. These mutants are able to emit light after induction by thallium ions. This biological method of thallium detection possesses high specificity and sensitivity (0.5 microM of metal). Such microbial cells can be used to quantify bioavailability of thallium part in the environment.

[Inhibitory effect of lead ions on cells of some strains of Pseudomonas species bacteria]. / Izuchenie ingibiruiushchego vliianiia ionov svintsa na kletki nekotorykh shtammov bakterii roda Pseudomonas.

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.

[Inducible surface proteins from some strains of Pseudomonas species bacteria while adapting to cobalt]. / Indutsibel'nye poverkhnostnye belki nekotorykh shtammov bakterii roda Pseudomonas v usloviiakh adaptatsii k kobal'tu.

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.