[Bartonella and bartonellosis--emerging and re-emerging infections: epidemiology, clinical course, diagnosis].

Information on the epidemiology, clinic and diagnostics of bartonellosis is updated. The importance of bartonellosis lies in the fact that its main risk group embraces patients with immunodeficiencies of different origin, the number of such patients constantly growing. The diagnostics of bartonellosis is insufficiently developed and the research on Bartonella organisms, except for the trunch (Volynia) fever causative agent, is insufficient in our country.

[Bartonella and bartonellosis--emerging and re-emerging infections. Taxonomy, bacteriology, pathogenesis and genetics]. / Bartonelly i bartonellezy--novye i vozvrashchaiushchiesia. Taksonomiia, bakteriologiia, patogenez i genetika.

The review updates knowledge on the taxonomy, bacteriology and genetics of Bartonella as well as pathogenesis of bartonellosis. The role of Bartonella in human pathology, formerly considered to be rather modest, causes now growing anxiety. In this connection Bartonella are now believed to be the causative agents of so-called emerging and re-emerging diseases, i.e. diseases, formerly unknown to man, and diseases, believed to be eradicated and playing at present no important role in human pathology. These microorganisms are a bright example of successes of molecular biology in the detection of microorganisms, as well as in their phylogenetics and systematics.

[Genotypic characteristics of Rickettsia sibirica strains]. / Genotipicheskaia kharakteristika shtammov Rickettsia sibirica.

Six Rickettsia sibirica strains isolated in Siberia and Far East (Primorje) from various sources (patient, ticks D. nuttali, D. silvarum, H. concinna) at different time (1940-1980) were studied by the RFLP and DNA probe hybridization techniques. All studied strains were found to have the identical profiles of migrating fragments in restrictograms got by using a set of endonucleases (EcoRI, PstI, PvuII, Bg1I, XbaI, HindIII, MspI) and similar zones of hybridization with a DNA probe derived from Rickettsia prowazekii DNA. The obtained data point to a close similarity between the genomes of investigated Rickettsia sibirica strains. Long-term isolation of the genetically similar Rickettsia sibirica strains testifies to their constant circulation, thus apparently determining the stability of epidemiologic manifestation of tick-borne typhus fever of Northern Asia in the central part of its area (Siberia, Far East).

[The role of R plasmids in the resistance of bacteria in air]. / Rol' R-plazmid v rezistentnosti bakterii v vozdukhe.

The study of Escherichia coli J 53, used as a model, has revealed that some R plasmids isolated from Serratia marcescens and Klebsiella pneumoniae, found to be the cause of the outbreak of hospital infection, ensure, besides multiple drug resistance, also their viability in the air.

[1 of the causes of a change in viability of Escherichia coli L1 in air]. / Ob odnoi iz prichin izmeneniia zhiznesposobnosti Escherichia coli L1 v vozdukhe.

The possibility of changing the fatty acid composition of lipids in E. coli strain BB 20-14 by the introduction of ready lipid vesicles obtained from other E. coli strains into the growth medium has been established. Using E. coli strain BB 20-14 as an example, the dependence of the viability of bacteria on their fatty acid composition has been demonstrated.

[Role of PSD2 and GPS A20 genes in lethal processes in Escherichia coli found in the air]. / Rol' genov PSD2 i GPS A20 v letal'nykh protsessakh Escherichia coli, nakhodiashchikhsia v vozdukhe.

Comparative experiments on auxotrophic E. coli grown in rich nutrient L-broth have demonstrated that the influence of genes psd 2 and gps A 20 responsible for the synthesis of phospholipids in the bacterial membranes on the viability of the cells is unessential. The cultivation of strain BB 20-14 in a minimal E medium with different glycerophosphate admixtures has shown that the decrease of phospholipid content in the cells to one-third of the original level leads to a considerable change in the viability of the cells in the air.

[Method of selecting Escherichia coli resistant and sensitive to aerosolization]. / Metod selektsii rezistentnykh i chuvstvitel'nykh k aérozolirovaniiu Escherichia coli.

The study made on E. coli used as a model has indicated that the selection of clones, resistant or sensitive to aerosol dispersion, can be carried out by storing the freeze-dried cultures of these clones in humid air for 2.5 hours.

[Analysis of the basic protein fractions of the outer membrane in E. coli strains differing in survivability in air]. / Analiz osnovnykh fraktsii belkov vneshnei membrany v shtammakh E. coli, razlichaiushchikhsia po vyzhivaemosti v vozdukhe.

The study of the spectrum of the main fractions of proteins contained in the outer membrane of E. coli strains has revealed the relationship between the composition of protein fractions in the outer membrane and the level of the survival of these bacteria in the air. The increased survival capacity of E. coli strain K12 after the transfer of pSA 50 plasmid has been found to correlate with the appearance of 2 molecular fractions in the outer membrane. The positions of these fractions correspond to the molecular weights 70,000 daltons and 80,000 daltons.

[Analysis of the potential for restoring E. coli cells, aerosolized in 30% relative humidity, by systems that repair UV damage]. / Analiz vozmozhnosti vosstanovleniia kletok E. coli, aérozolirovannykh v usloviiakh 30% otnositel'noi vlazhnosti, sistemami, vosstanavlivaiushchimi UF-povrezhdeniia.

The mutants, defective due to a complex of damages caused by UV radiation, are considerably more sensitive to aerosol dispersal under conditions of 30% relative humidity than their parent strains. The sensitivity of bacteria to dispersal by aerosol, equally increasing in case of mutations in any of the tested reparative genes, is not linked with their incapability to repair DNA damages, but should be rather considered as a pleiotropic effect. Strains E. coli K12 are somewhat more sensitive to aerosol dispersal than E. coli B when sprayed on fiberglass under conditions of 30% relative humidity.

[Intergeneric conjugational crossing of Escherichia coli with Salmonella typhimurium. II. Transfer of a polA1 mutation from Escherichia coli to Salmonella typhimurium and its phenotypic expression in the salmonella genome]. / Mezhrodovoe kon"iugatsionnoe skreshchivanie Escherichia coli i Salmonella typhimurium. Soobshchenie II. Perenos polA1-mutatsii ot Escherichia coli k Salmonella typhimurium i ee fenotipicheskoe vyrazhenie v genome sal'monell.

The Escherichia coli structural gene for DNA polymerase I was inserted into Salmonella typhimurium chromosome by conjugal transfer. The genetic analysis of P1-mediated transduction of obtained hybrid showed that polA gene is located in it between metE and rha loci and is cotransduced with metE (about 50%) and rha (12%). The phenotypic properties of polA1 hybrid E. coliXS. typhimurium concerning UV-MMS-NG and gamma-ray sensitivity are similar to the polA1 mutants of E. coli.