[The interaction of pathogenic microorganisms with the sorbent polymethylsiloxane]. / Izuchenie vzaimodeistviia patogennykh mikroorganizmov s sorbentom polimetilsiloksanom.

The method of electron microscopy has been used to study adhesion of the microbic cells of standard strains of Staphylococcus aureus, Escherichia coli and fungi of genus Candida on the organosilicon sorbent polymethylsiloxane (PMS) and medicamentous complex containing it. This complex contains furazolidone and metronidazole immobilized on silver ions-modified PMS. It is shown that the adhesion of microorganisms is accompanied by their destruction whose rate on pure PMS and medicamentous complex is different. Using experimental data the assumptions are advanced concerning the mechanism of the PMS interaction with Gram-positive and Gram-negative microorganisms as well as with fungi of genus Candida.

[An electron microscopic study of the structure of Erwinia carotovora 268 bacteria]. / Elektronno-mikroskopicheskoe issledovanie struktury bakterii Erwinia carotovora 268.

The electron-microscopic studies have shown that the bacterium Erwinia carotovora 268 (a producer of L-asparaginase) does not differ essentially from other representatives of enterobacteria. When growing on the artificial nutrient medium M9, the division of bacteria is inhibited and the bacterial cell itself elongates. Certain functionally specified structural peculiarities such as the formation of the protein microcapsule, formation of cavities and compacted sites of the cytoplasm and mucus on the cell poles are typical of bacteria, that is associated with the synthesis of L-asparaginase and erwiniocinogeny.

[Restriction map of permuted DNA of Erwinia carotovora temperate bacteriophage 59]. / Restriktsionnaia karta permutirovannoi DNK umerennogo bakteriofaga 59 Erwinia carotovora.

The cyclic permutation and terminal redundancy were found in the genomes of Erwinia carotovora temperate bacteriophage 59 by electron microscopic studies. The headful mechanism for bacteriophage DNA cleavage and packaging during the phage morphogenesis was confirmed by the restriction analysis technique. Restriction map of the bacteriophage 59 DNA was constructed for restriction endonucleases BamHI, Bg1II, Eco31, Sa1I, SmaI, EcoRI.

[Bacteriocins of species of the genus Pseudomonas]. / Bakteriotsiny nekotorykh vidov roda Pseudomonas.

Occurrence of bacteriocinogeneity in 120 strains of 24 species of Pseudomonas was studied. Active strains producing bacteriocine-like substances were detected among P. fluorescens, P. putida, P. taetrolens, P. fragi, P. stutzeri, P. mendocina, P. maltophilia, and P. pseudoalcaligenes. The bacteriocine-like substances produced by them differed by the morphology of the zones of the test microbe growth inhibition, sensitivity to temperature and enzymes, capacity for dialysis through cellophane membranes and antimicrobial spectrum. The majority of them could be synthesized on agarized and liquid media and induced by UV light and mitomycin C. The strains of P. taetrolens, P. fragi, P. putida and P. fluorescens producing the bacteriocine-like substances had broad antimicrobial spectrum and inhibited the growth of many species of Pseudomonas and representatives of other taxonomic groups of microorganisms.

Structure of Erwinia carotovora temperate bacteriophage 59 and its DNA.

The temperate phage 59 from Erwinia carotovora and its DNA were studied. The phage particles have an icosahedral head and a long noncontractile tail with a base plate. The virus DNA makes up 50% of the total virus and exists as a linear molecule (molecular weight, 2.6 X 10(7)). A model of virus structural organization is presented.

[Electron microscopic structure of Erwinia carotovora moderate phage 59 and its DNA]. / Elektronno-mikroskopicheskaia struktura umerennogo faga 59 Erwinia carotovora i ego DNK.

Electron microscopic examinations showed the moderate phage 59 Erwinia carotovora to consist of a head of icosahedral shape 50.0+/- +/-2.5 nm in diameter, a noncontractile process 150.0+/-3.5 nm in length and 8.2+/-1.0 nm in diameter with a basal plate of 20.0+/-1,5 nm. The head of the virion of 45.9 X 10(3) nm3 in volume is formed by 812 morphological subunits about 3.0 nm in diameter; the number of structural subunits is 4860 on the basis of triangulation number (81). The process of the virus is cross-striated, the pattern being formed by 35+/-1 rows (43+/-5 A) of subunits 3.0 nm in diameter. The total number of subunits in the process is 210+/-6. DNA of the virus under study has a trend of ring formation. Its modal length is 14.61+/-0.53 micron corresponding to a molecular weight of 28.66+/-1.04 X 10(6) daltons. The volume of DNA molecule is 45.9 X X 10(3) nm3, indicating that a portion of phage DNA is in the virion, probably in denaturated state. An electron microscopic model of the organization of the virus under study is proposed.

[Manifestation of polylysogeny in Pseudomonas vignae]. / Iavlenie polilizogenii u Pseudomonas vignae

Ultraviolet irradiation and treatment with mitomycin C demonstrated that a culture of Ps. vignae, strain 1025, was polylysogenic, as electron microscopic preparations of phagolysates revealed two types of virus particles: "large" with a hexagonal head of 700 A in diameter, and "small" with a round head of 500 A in diameter. Subcultivation of the test and indicator cultures showed in both cases formation of particles of these phages, the content of "small" virions increasing with the number of passages of negative colonies. Attempts to separate these viruses biological methods were not successfull. The phenomenon of polylysogeny is unusual in that moderate phage adsorbed repeatedly on host bacteria culture and lysed it. The causes of the discovered phenomenon are discussed.