Search

Introduction. The Mollicutes class unites cell wall lacking bacteria many of which are membrane parasites and opportunistic bacteria. Aim . This study describes a novel morphological form found in the five species belonging to the bacterial class Mollicutes, and referred to as microcolonies (MCs). Methodology. MCs were obtained as described below and characterized with bacteriological and immunological methods, and microscopy. Results. In contrast to typical colonies (TCs), MCs are characterized by tiny propeller-shaped colonies formed by rod-like cells tightly packed in parallel rows. These colonies were observed within routinely cultivated cultures of type strains 7-12 days post-plating. Rod-like cells were visualized using a scanning electron microscope within TCs with a 'fried-egg-like' appearance. MCs were not observed to revert to TCs. MCs were resistant to antibiotics and other treatments effective against TCs. Pure MC cultures were generated in vitro by treatment of Mycoplasma cultures with hyperimmune serum, antibiotics or argon non-thermal plasma. MCs of Mycoplasma hominis strain H-34 were characterized in detail to confirm that they belonged to that species. MCs tested positive via PCR with M. hominis -specific primers, direct fluorescence and epifluorescence tests, and Western blotting with the camel-derived nanobody aMh-FcG2a, which is specific to the MH3620 transporter protein. Meanwhile, MCs behaved differently in standard bacteriological tests. Pure MC cultures were also isolated directly from clinical samples of the serum, synovial liquid and urine of patients within flammatory urogenital tract diseases, asthma or arthritis. In total, 79 independent MC cultures were isolated from clinical samples including M. hominis ( n =70), Mycoplasma pneumoniae ( n =2), Mycoplasma fermentans ( n =2) and Mycoplasma spp. ( n =5). Conclusion . MCs play an unknown role in infection pathology and display prominent antibiotic resistance, making them a challenge for the future studies on Mollicutes.

Aim: Study the influence of low temperature (cold) electrolyte plasma (CEP) on survivability of some mycoplasma strains growing in agar as well as mycoplasma that most frequently contaminate transplantable human cell lines of normal and malignant origin with the aim of decontamination., Materials and Methods: Mycoplasma hominis, Mycoplasma arginini and Aholeplasma laidlawii grown in agar and mycoplasma that contaminated transplantable human cell lines of normal (MT4) and malignant (HeLa) origin. Plasma source--Plasmatom device that generates CEP at normal atmosphere pressure and environment temperature. Exposure to plasma was carried out with adherence to the same modes for all the variants of biological substrate. The duration of exposure was selected randomly from 15 to 300 seconds., Results: A pronounced bactericidal effect of high doses of CEP on all the tested mycoplasma variants exposed immediately after seeding into agar was shown. However after a passage a residual number of survived colonies was registered. Passage of colonies exposed in grown state even to high doses of CEP also showed survival of a residual number of bacteria in all the tested mycoplasma species. Exposure of M. hominis immediately after seeding to low doses of CEP resulted in formation of unusual mini-colonies identical to those isolated from humans infected by the same mycoplasma. During microbiological seeding into agar of cultural fluid from 2 spontaneously contaminated strains of transplantable human cells and exposed to CEP growth ofmycoplasma was not detected., Conclusion: CEP has pronounced bactericidal properties on various mycoplasma strains growing in both agar and contaminating eukaryotic cells. However even at high doses of exposure to CEP an insignificant part of bacterial cells growing in agar still survives. This may indicate a high degree of heterogeneity and adaptation of mycoplasma subjected to even such hard exposure as cold plasma with plasma-chemical mechanism of destruction of biological substrate.

The antigens, DNA and RNA of mycoplasmas are preset in the blood serum of persons infected with urogenital mycoplasmas. The planting of patients' tests of blood serum containing antigen M. hominis on the artificial growth mediums resulted in the growth of mini-colonies of mini-cells (20-50 nm). The colonies subcultured hardly but sometimes formed solid bacterial lawn though never acquired "fried-egg" classical mycoplasma form. The proofs of identity of these colonies to M. hominis are presented. The mini-cells possessed infectiousness and ability to persist on a long-run in the internal organs of experimentally infected mice. Apparently, mini-cells are formed under impact of stress factors of the host immune defense and they are one of forms of mycoplasma's persistence in human organism.

Aim: Until now, the problem of effective therapy of HIV-infection is not resolved due to integrative type of interaction of HIV virus with target cell - T-lymphocyte. The study was aimed on search of method of deletion of HIV DNA-provirus from cell's genome., Materials and Methods: Non-pathogenic for humans Mycoplasma arginini was used for coinfection of HIV-infected cells in model systems in vitro., Results: Complex of mechanisms was documented leading to: blocking up to 50 - 60% of extracellular virus (according to titration results), cancel of apoptosis in infected cells stained on Hoechst, formation of defective vif(-) virions, which together with arginine-desaminase of M. arginini arrange permissive conditions for activation of cellular APOBEC3G with subsequent disruption of DNA- provirus and blocking of viral infection. As studies of ultrastructure showed, listed events resulted from direct interaction of HIV with mycoplasma., Conclusion: The elimination of HIV DNA-provirus is possible by co-infection of T-lymphocytes with M. arginini.

Presented are the data on the ultrastructural analysis of interaction between mycoplasma and certain cancerogenic and infectious viruses in humans and animals. Revealed are spontaneous associations of mycoplasma with viruses of cattle leukemia, T-cell human leukemia and with a representative of Bunyaviruses. Immediate interaction of these agents is found possible. Simulated complexes of mycoplasma with infectious viruses are developed. Electron microscopy on supramolecular levels revealed immediate interaction of different agents in membranes. Some methodological procedures help to reveal that the interaction of M. pneumoniae and A. laidlawii with orthomyxo-, paramyxo and togavirus is of specific character and is realized as receptor ligand form due to the affinity in the receptor requirements of these pathogens. This property as well as a bequeath distribution and frequent association in respiratory infections enable one to suggest the possibility of their immediate interactions in a host body.

FLK cell culture chronically producing bovine leukemia virus (BLV) and spontaneously contaminated with mycoplasma (M. sp.) was studied by electron microscopy. Information on the features of the ultrastructural organization of M. sp. and its direct relationships with BLV was obtained. BLV virions are capable of adsorbing on mycoplasma surface and penetrate inside, apparently in the course of phagocytosis. In the cytosole of M. sp. free-lying BLV virions devoid of the limiting membrane were found. In FLK cells both agents were regularly produced in high amounts causing no signs of death of the cell culture itself. From the foregoing, the FLK cells--BLV-M. sp. system appears to be quite balanced.

A suspension culture of human T-lymphoblasts HUT-102 producing type C oncovirus (HTLV) was examined electron microscopically. Control decontaminated HUT-102 cells spontaneously contaminated with M. orale and exogenously infected with M. pneumoniae were examined in ultrathin sections. The variation statistics method demonstrated that in the mycoplasma-infected cells the number of HTLV virions was significantly higher than in control cultures. It is assumed that the increased production of HTLV is due to mycoplasma-induced changes of physico-chemical properties of the cell membrane which facilitate virion budding.

Mycoplasma sp. previously isolated from sheep embryo kidney cells producing bovine leukemia virus (FLK-BLV) was serologically identified in the growth inhibition test as M. arginini. SDS-PAGE of cellular proteins demonstrated their identity in M. sp. and M. arginini. Upon artificial inoculation of FLK cells, M. arginini persisted in the cells for a long time and was detectable in high titres by all the methods used. Other species of mycoplasma were isolated from the cells by microbiological method but were detectable by other methods in first passages only. The phenomenon of "disappearance" of mycoplasma was not associated with the toxic effect on them of the ingredients used in cell propagation and of cell metabolism products. It is assumed that sheep embryo cells, M. arginini, and bovine leukemia virus is a fortunate biological model of natural infection.