Energetic aspects of CO oxidation in desulfovibrio desulfuricans

In cell suspension of Desulfovibrio desulfuricans B-1388, oxidation of CO as the only energy source is associated with reduction of SO42-. After a 2-h incubation of cells in 8% CO, 81% of the gas is converted. Oxidation of 1 mole CO results in formation of 0.23 mole H2S. Intracellular ATP content increases from 2.5 (control) to 8.3 nmoles/mg (during CO conversion). Dinitrophenol inhibits sulfate reduction and CO oxidation. CO dehydrogenase was detected in cytoplasmic and membrane cell fractions (59 and 34%, respectively).     

Romanowsky staining,the Romanowsky effect and thoughts on the question of scientific priority

I give an historical account and analysis of the scientific priority of the discovery of the polychrome staining of microscopic biological preparations provided by mixtures of eosin plus methylene blue and its derivatives, especially azure B. I maintain that both the formal priority for the discovery of the polychrome staining phenomenon and credit for initiating the development of a technique of polychrome staining properly belong to D. L. Romanowsky. His scientific work demonstrated the possibility of using a simple technique to stain hematological preparations selectively to give good contrast, high resolution and the ability to identify malaria parasites. Romanowsky’s approach constituted the starting point for the development of a family of polychrome stains for microscopic investigation of hematological preparations by a number of his contemporaries.     

Characteristics of plague pathogen mutants,differing by pigment sorption signs

Wild-type strains of plague agent Yersinia pestis are characterized by a pigmentation phenotype (Pgm+), which includes several traits: an ability of cells to adsorb pigments (Hms+), an ability to produce siderophore yersiniabactin (Ybt+) and an ability to cause lethal infections in laboratory animals (Vir+) after subcutaneous injections. All these traits are encoded in the chromosomal pgm-locus, which gets rapidly lost due to deletion. One more trait related with the Pgm+ phenotype was detected in the present study, i.e. its siderophoric activity at 28 degrees C on the indication agar plates containing chrome azurol S (Sid+). After the four phenotypic characteristics of the Pgm+ phenotype were analyzed as well as after the four pgm-locus genes (hmsF, hmsR, irp2 and fyuA/psn) were detected by the method of hybridization and PCR, we compared 33 isogenous Pgm- mutants isolated from typical Y. pestis strain 923 by Hms-. The comparison showed that the mutants differed from each other according to the analyzed properties, which suggested that they were formed by different genetic mechanisms. Apart from the known mechanism of pgm-locus deletion, which causes an irreversible loss of Hms+, Ybt+ and Vir+ properties, two more mechanisms were detected. One of them is related with insertion damages to the pgm-locus genes, which also leads to the loss of the four traits but which can be reversed by the cultivation of cells at low temperature. The other mechanism is predetermined by unknown genetic processes ensuring the formation of mutants, which loose only their Hms+ properties and which can trigger its high-frequency reversion at 28 degrees C.     

Improvement of the method for the indication of the causative agent of anthrax

A combined method for the indication of the causative agent of anthrax (Bacillus anthracis), including the preparation of the material to be tested, the exposure of the magneto-imunosorbent in the sample, cultivation in selective medium, DNA extraction with subsequent testing in the polymerase chain reaction with primers to genes cap, pag and chromosomal sequence Ba813, the registration and interpretation of results, has been developed. All determinations, including the preparation of samples, last not more than 6 hours. The indication of B. anthracis by the proposed method makes it possible not only to confirm its presence in the sample Under test, but also to evaluate its epidemic potential.     

Comparative Analysis of Genotyping Methods for Bacillus anthracis

Russian Journal of Genetics - Genetic typing of the anthrax causative agent is used in epidemiological investigations of infection outbreaks and serves as a tool for studying the evolution of this...     

Obtaining immunoglobulin-binding sorbent by immobilization of recombinant human proinsulin protein A domain fusion protein

Summary Recombinant human proinsulin - protein A domain fusion protein (rPFP) was immobilized on synthetic matrix, resulting in inexpensive immunoglobulin-binding sorbent. This is an alternate to a protein A affinity support. A Standard technique was used for immobilization. Experiments, optimizing in ligand concentration, were performed.     

Effect of aminazine and triftazin on the synaptosome membranes of the rat cerebral cortex

Fluorescent probes 1,6-diphenyl-1,3,5-hexatriene (DPH) and pyrene were employed in studying the effect of aminazine and triftazin versus that of imipramine on microviscosity of rat brain cortex synaptosomal membranes. Unlike imipramine, the neuroleptics decrease microviscosity of membrane's lipid bilayer. All drugs decrease fluorescence of endogenous tryptophan, but fail to change fluorescence of L-tryptophan in the solution. It is concluded that neuroleptics induce conformational perturbations in membrane-bound proteins modifying microviscosity of lipid bilayer whereas imipramine changes the surface electric charge of lipid bilayer of synaptosomal membranes.     

Interaction of psychotropic preparations with the synaptic membranes of the cerebral cortex in rats

Interaction of psychotropic drugs with synaptosomal membranes from rat brain cortex was investigated by fluorescent probes. The data obtained indicate that all studied drugs change the state of membrane's surface. Tranquilizers, unlike antidepressants and neuroleptics, decreased fluorescence of the probe. Neuroleptics, unlike other drugs, penetrated deeper into the membranes hydrophobic core.     

Effect of subchronic administration of phenazepam and synthetic antioxidants on the functional status of synaptic membranes in the cerebral cortex of rats subjected to prolonged stress

Monoamine oxidase activity, lipid peroxidation and membrane structure were tested after chronic stress and 7-day treatment with drugs in the brain cortex synaptosomal membranes of rats. The most potent corrector of stress-induced changes, as compared to hydrophobic antioxidant dibunol and tranquilizer phenazepam, was compound 3-OP, a hydrophilic antioxidant.