[Study of the quality of aminated substrates used for hybridization analysis].

A set of methods for analysis of the quality of aminated substrates that could be a basis for the large-scale manufacturing of biological microchips is suggested. The analysis includes the determination of the number of amino groups, their availability for the immobilization of phosphorylated oligonucleotides, and the characterization of surface properties of the substrates in respect to the nonspecific sorption of reagents during hybridization. A simple procedure was suggested for determination of the density/number of amino groups. It is based on the use of dimethoxytrityl chloride with the subsequent spectrophotometric determination of dimethoxytrityl cation. The availability of amino groups was estimated by covalent attachment of an oligonucleotide probe containing a fluorescently labeled group to the aminated surface and the subsequent comparison of the intensity of fluorescing zones formed on the chip. The sorption properties of the surface were investigated with the help of a model hybridization reaction. A comparative analysis of aminated glasses manufactured by various firms and in our laboratory showed that the glasses with the amino group density from 0.7 to 2.0 groups/nm2 prepared by our procedure have the best properties for the hybridization analysis.

[Loach spermatozoa transfer foreign DNA, which expression is discovered in the early development stages]. / Spermatozoidy v'iuna perenosiat chuzherodnuiu DNK, ékspressiia kotoroi obnaruzhivaetsia na stadiiakh rannego razvitiia.

The transfer of plasmid pcDNA3-lacZ by electrotrasfected sperm cells into loach (Misgurnus fossilis L.) ova has been studied. The lacZ gene has been found to express in 3- to 5-day-old prelarvae.

[Study of the transfer of foreign genes into mussel Mytilus Galloprovincialis Lam. eggs by spermatozoa]. / Issledovanie perenosa chuzherodnykh genov spermatozoidami v iaitsekletki midiii Mytilus Galloprovincialis Lam.

The possibility of transferring exogenous DNA into eggs by mussel Mytilus galloprovincialis Lam. sperms both with the use of certain methods of transfection and without them was studied. The efficacy of egg fertilization by sperms treated with foreign DNA and the development of larvae at early stages of embryogenesis were evaluated. Negative effects of the contact between mussel sperms and exogenous DNA on fertilization and subsequent development were noted. The proportion of developing larvae decreased with increasing DNA concentration and sperm exposure. Transfer of plasmids pCMVlacZ and pMTbGH into eggs was observed in group crosses. With the use of PCR, foreign DNA sequences were found in the larvae at the stage of veliger 48 h after fertilization. An intense signal was recorded after sperm electroporation in 10% DMSO.

[Comparative effectiveness of antioxidants in protecting the bacterial plasmatic membrane from the active froms of oxygen]. / Sravnitel'naia éffektivnost' antioksidantov pri zashchite bakterial'noi plazmaticheskoi membrany ot aktivnykh form kisloroda.

The effect of hydroxyl radicals OH. generated by the decomposition of H2O2 by Fe2+ ions (Fenton reaction) on the barrier properties of plasma membranes of Escherichia coli cells K-12 was studied by electroorientation spectroscopy. It was found that the administration of hydrogen peroxide led to the disturbance of the barrier properties of plasma membranes only when the cells were preincubated with Fe2+ ions and their constant concentration in the system was maintained by ascorbate or dithiotreitol (150-500 microM). The extent of the toxic action on plasma membranes depended on the concentration of reacting elements and the substance used as a reducer Fe2+. The efficiency of protection of antioxidants of different classes (enzymic, SH-containing, and phenolic compounds) against the toxic action of hydroxyl radicals on plasmatic membranes was shown.

[Resistance of certain strains of Pseudomonas bacteria to toxic effect of heavy metal ions]. / Ustoichivost' nekotorykh shtammov bakterii roda Pseudomonas k povrezhdaiushchemu deistviiu ionov tiazhelykh metallov.

The effect of heavy metal cations (cobalt, nickel, and copper) and the anion detergent sodium dodecyl sulfate (SDS) on the barrier properties of the plasma membrane (PM) of the Co-sensitive stain Pseudomonas putida BS394 and the Co-resistant strains Pseudomonas sp. BS501 (wild-type strain) and Pseudomonas putida BS394 (pBS501) (transformed strain) was studied by high-frequency electro-orientational spectroscopy. The cations were found to rank, in order of decreasing damage inflicted on the PM, as copper > cobalt > nickel. The strains studied were found to rank, in order of increasing resistance of the PM to damage inflicted by copper and cobalt cations, as P. putida BS394 < P. putida BS394 (pBS501) < Pseudomonas sp. BS501. In order of increasing resistance to SDS, the strains ranked inversely. The strains did not differ in sensitivity to nickel cations. Investigation of the surface of intact and trypsin-treated cells by microelectrophoresis showed that the surface layers of the cell wall of wild-type and transformed cells contained increased amounts of proteins. The surface proteins of Co-resistant cells had molecular masses of 49, 40, and 32 kDa. Exposure of Co-resistant cells to trypsin considerably reduced their resistance to cobalt cations. It is assumed that the resistance of the PM of the wild-type and transformed pseudomonads to heavy metal cations is determined by plasmid pBS501 and is related to the synthesis of protective surface proteins of the cell wall.

[Study of the interaction of MTPN11 mycobacteriophage with host cells based on electron microscopy, fluorimetry, and electro-oriented spectroscopy]. / Izuchenie vzaimodeistviia mikobakteriofaga MTPN11 s kletkoi-khoziainom na osnove élektronnoi mikroskopii, fluorimetrii i élektro-orientatsionnoi spektroskopii.

According to electron-microscopic data, various cells in the M. smegmatis ATCC607 population interact differently with phage MTPH11. Fluorometric studies of phage-host interactions were performed using a membranotropic fluorescent probe, 8-anilino-1-naphthalene sulfonate (ANS). Changes in the electric characteristics of mycobacterial cells infected with the phage were studied by electro-orientational (EO) spectroscopy. The problem of the employment of fluorometry and EO spectroscopy for rapid phage typing of mycobacteria is discussed.

[Initial stages of interaction of temperate phage 04 with Pseudomonas aeruginosa cells]. / Izuchenie nachal'nykh stadii vzaimodeistviia umerennogo faga 04 s kletkoi Pseudomonas aeruginosa.

The first steps of the interaction of the temperate pilus-dependent phage 04 with susceptible and 04-lysogenic cells of Pseudomonas aeruginosa were investigated. The 04-lysogenic cells retained their ability to adsorb viral particles on the pili. However, after the translocation to the cell surface, the bacteriophage failed to infect the immune microorganism. It is assumed that was modified the surface of 04-immune cells due to lysogenic conversion, and this modification presented the terminal tail fibers of viral particles interacting from with the outer membrane of P. aeruginosa cells.

[Toxic effect of hydroxylated ions of heavy metals on the cytoplasmic membrane of bacterial cells]. / Toksicheskoe deistvie gidroksilirovannykh ionov tiazhelykh metallov natsitoplazmaticheskuiu membranu bakterial'nykh kletok.

The influence of nickel, copper, cadmium, and lead ions at concentrations of 50 to 100 microM on the barrier properties of the plasma membrane (PM) and the electrophoretic mobility (EPM) of Pseudomonas fluorescens 71, Escherichia coli K-12, and Mycobacterium phlei B-1291 VKM cells was studied at pH values from 5 to 9 by electro-orientational (EO) spectroscopy and microelectrophoresis of cells. According to the data of EO spectroscopy, the increase in the toxicity of heavy metal cations to cells corresponded to transition of cations to monovalent hydroxylated forms. Hydroxylated ions were found to more easily adsorb on, or penetrate across, the PM and to bind to competent proteins. During the treatment of all three investigated microorganisms with Cu and Pb ions, and gram-negative bacteria also with Ni ions, the EPM of cells changed in a pH range corresponding to the transition of bivalent metal ions to their monovalent hydroxylated forms. Changes in the EPM induced by increasing pH correlated well with the enhanced toxicity of these metals to the PM, as evidenced by the EO spectroscopy data. At the same time, this correlation was less pronounced for cadmium sulfate toxicity to all of the microorganisms studied and for nickel chloride toxicity to M. phlei cells.

[Electrophoretic mobility of UV-irradiated bacterial cells]. / Elektroforeticheskaia podvizhnost' UF-obluchennykh bakterial'nykh kletok.

Electrophoretic mobility of Escherichia coli cells exposed to various doses of UV-radiation was investigated. The method of free flow electrophoresis was used to study a correlation between membrane protein charge and cell surface electric charge. The change in the cell surface charge and electrophoretic motility was associated with the damage to membrane proteins and the survival of UV-irradiated bacteria.