[Manganese in atherogenesis: detection, origin, and role].

The role of transition metal ions in atherogenesis is controversial; they can participate in the hydroxyl radical generation and catalyze the reactive oxygen species neutralization reaction as cofactors of antioxidant enzymes. Using EPR spectroscopy, we revealed that 70% of the samples of aorta with atherosclerotic lesions possessed superoxide dismutase activity, 100% of the samples initiated Fenton reaction and demonstrated the presence of manganese paramagnetic centers. The sodA gene encoding manganese-dependent bacterial superoxide dismutase was not found in the samples of atherosclerotic plaques by PCR using degenerate primers. The data obtained indicates the perspectives of manganese analysis as a marker element in the express diagnostics of atherosclerosis.

[The adaptation of mycoplasmas to stress conditions: features of proteome shift in Mycoplasma hominis PG37 under starvation and low temperature].

Mycoplasma hominis--one of the widely spread mycoplasmas (class Mollicutes), associated with the socially significant human diseases and contamination of cell cultures. The solution of the problem on controlling M. hominis infections is connected with determination of the molecular basis, responsible for mechanisms of bacterium survival under unfavorable conditions. As a result of proteomic approach (2-DIGE and MALDI TOF/TOF MS) for the first time, 53 M. hominis PG37 proteins were detected, different abundance of which occurred at cultivating the bacterium under stress (starvation and low temperature) conditions. According to the classification of proteins by functional category (clusters of orthologous groups of proteins--COG), 47 of the 53 proteins of the mycoplasma are involved in the fundamental cellular and biochemical processes--translation (12; 22.64%), transcription (2; 3.77%), posttranslational modification (7; 13.20%), cell cycle control (2; 3.77%), energy production and conversion (6; 11.32%), carbohydrate transport and metabolism (3; 5.66%), amino acid transport and metabolism (8; 15.09%), nucleotide transport and metabolism (6; 11.32%), inorganic ion transport and metabolism (1; 1.89%). The functions of six proteins (11.32%) have not been found; 24 proteins (45.28%) are the factors of bacterium virulence. M. hominis PG37 proteins, the expression modulation of which arises under the unfavorable environmental conditions, are the components of adaptation mechanisms of the mycoplasma to the stressors and potential targets for controlling infections caused by this bacterium.

[Adaptation of mycoplasmas to stressful factors: nucleotide sequences nonregistered in vegetative forms of M. galisepticum S6 cells are revealed in nonculturable forms of the mycoplasma].

Adaptation of M. gallisepticum S6 to unfavorable environmental conditions is connected with transformation of the vegetative forms of the mycoplasma cells to the viable but non-culturable (VBNC) forms. The vegetative forms and the VBNC forms differ in the spectrum of the PCR-products that was forming due to amplification of the nucleotide sequence of the pvpA-gene coding the able cytoadhesion protein. As to vegetative forms of the mycoplasma the only amplicon, containing one open reading frame (1086 b.p.) with a high homology (97%) to the pvpA-gene of M. gallisepticum R and Pendik is detected. In the case of VBNC forms of M. gallisepticum S6, the additional amplicons besides those indicating the pvpA-gene of the mycoplasma are observed. In the nucleotide sequences of the additional amplicons, the open reading frames are detected that are not registered in the database of the complete sequence of the mycoplasma genome. A high homology (54-55%) of the nucleotide sequences of the pvpA-gene and the additional pvpA-amplicons allows to suggest that thepvpA-gene sequence seems to be a basis for forming new regions within the mycoplasma genome during adaptation of the bacterium to unfavorable environmental conditions.

[Peculiarities of genotype distribution of interleukins (IL-1 and IL-10) in patients with peptic ulcer disease and their associations with persistence of Mycoplasma hyorhinis and Helicobacter pylori genotypes].

It was found for the first time in our study that there is a significant prevalence of combinations of IL-1 and IL-10 genotypes--IL-1B-511C/C, IL-1B+3954C/C, IL-1RN1/1, IL-10-1082A/A and IL-1B-511T/C, IL-1B+3954C/C, IL-1RN1/2, IL-10- 1082A/G--in the group of patients with gastric and duodenal ulcer disease and control one, respectively. The correlation between the Tox- (cagA- vacAs1-) strains of H. pylori and the combinations of genotypes IL-1B-511T/C, IL-1B +3954C/C, IL-1RN1/1, IL-10-1082G/G was shown (p <0,05). Co-infection with H. pylori and M. hyorhinis was detected in 19% of patients. The association between combinations of genotypes IL-1B-511T/T IL-1B+3954C/C, IL-1RN2/2, IL-10-1082A/G and co-infection with H. pylori and M. hyorhinis was also found (p <0,05).

[Adaptation of Mycoplasma gallisepticum to unfavorable growth conditions: changes in morphological and physiological characteristics].

Adaptation of Mycoplasma gallisepticum to unfavorable growth conditions results in altered morphological and physiological characteristics of the cells. M. gallisepticum populations in a complete nutrient medium contain pear-shaped vegetative cells (d approximately 0.3 microm; l approximately 0.8 microm) with pronounced polar and cytoskeleton-like structures. Such mycoplasma cells are able to induce damage in a bacterial genome, causing an SOS response of the test strain (Escherichia coli PQ37). In a starvation medium, M. gallisepticum produces nanoforms, small coccoid cells (d approximately 0.15-0.2 microm) without either polar or cytoskeleton-like structures. Unlike vegetative cells, nanoforms do not induce genome damage. Alleviation of unfavorable growth conditions results in a reversion of nanoforms to typical vegetative cells.

Periplasmic superoxide dismutase from Desulfovibrio desulfuricans 1388 is an iron protein.

It is shown that the genome of the sulfate-reducing bacterium Desulfovibrio desulfuricans 1388 contains a superoxide dismutase (SOD) gene (sod). The gene encodes an export signal peptide characteristic for periplasmic redox proteins. The amino acid sequence showed high homology with iron-containing SODs from other bacteria. Electrophoretically pure SOD was isolated from the periplasmic fraction of bacterial cells by FPLC chromatography. Like other Fe-SODs, D. desulfuricans 1388 superoxide dismutase is inhibited by H2O2 and azide, but not by cyanide.

[Genotyping Yersinia pestis strains from various natural foci]. / Genotipirovanie shtammov Yersinia pestis iz razlichnykh prirodnykh ochagov.

Seven genetic variants of Yersinia pestis were detected by finger-printing of 85 strains of this bacterium from natural foci by means of a BX probe. Variants of Y. pestis strains correlate with certain species of carriers.

[Comparative study of the structure of some genetic probes used for typing Yersinia pestis strains]. / Sravnitel'noe izuchenie struktury nekotorykh geneticheskikh zondov, ispol'zuemykh dlia tipirovaniia shtammov Yersinia pestis.

A nucleotide sequence common for genetic probes used for detection and investigation of Y. pestis strains MK, IS100, and HRSIII was identified on the basis of restriction, hybridization, and computer analysis. This region of chromosomal DNA is a part of low-molecular BX-probe (about 170 bp) we have developed. The results of genomic fingerprinting of Y. pestis strains by the BX-probe are promising as regards its future utilization for typing the strains isolated in various endemic areas.