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Infection and Immunity Jan 1977Mycoplasma pneumoniae cells were rounded and killed by fresh guinea pig serum (GPS) which did not contain detectable amounts of antibody. The first component of...
Mycoplasma pneumoniae cells were rounded and killed by fresh guinea pig serum (GPS) which did not contain detectable amounts of antibody. The first component of complement (C1) was bound by M. pneumoniae in considerable amounts from both GPS and purified C1. The C1 bound by the cells was reacting with C4. Sequential addition of C1, C4, C2, and C-ethylenediaminetetraacetate to glass-grown M. pneumoniae cells resulted in rounding of a significant number of cells. M. orale and M. fermentans showed a reduced binding capacity for C1 as compared with M. pneumoniae. Both species were only slowly killed by fresh GPS, whereas M. hominis was as sensitive as M. pneumoniae. The results suggest an antibody-independent interaction between some components of the membrane surface of M. pneumoniae and C1, resulting in an activation of the complement system leading to the killing of the mycoplasma cells.
Topics: Animals; Binding Sites, Antibody; Blood Bactericidal Activity; Complement C1; Complement System Proteins; Guinea Pigs; Mycoplasma
PubMed: 832909
DOI: 10.1128/iai.15.1.7-12.1977 -
Applied and Environmental Microbiology Sep 2015Nucleic acid amplification technique (NAT)-based assays (referred to here as NAT assays) are increasingly used as an alternative to culture-based approaches for the...
Nucleic acid amplification technique (NAT)-based assays (referred to here as NAT assays) are increasingly used as an alternative to culture-based approaches for the detection of mycoplasma contamination of cell cultures. Assay features, like the limit of detection or quantification, vary widely between different mycoplasma NAT assays. Biological reference materials may be useful for harmonization of mycoplasma NAT assays. An international feasibility study included lyophilized preparations of four distantly related mycoplasma species (Acholeplasma laidlawii, Mycoplasma fermentans, M. orale, M. pneumoniae) at different concentrations which were analyzed by 21 laboratories using 26 NAT assays with a qualitative, semiquantitative, or quantitative design. An M. fermentans preparation was shown to decrease the interassay variation when used as a common reference material. The preparation was remanufactured and characterized in a comparability study, and its potency (in NAT-detectable units) across different NATs was determined. The World Health Organization (WHO) Expert Committee on Biological Standardization (ECBS) established this preparation to be the "1st World Health Organization international standard for mycoplasma DNA for nucleic acid amplification technique-based assays designed for generic mycoplasma detection" (WHO Tech Rep Ser 987:42, 2014) with a potency of 200,000 IU/ml. This WHO international standard is now available as a reference preparation for characterization of NAT assays, e.g., for determination of analytic sensitivity, for calibration of quantitative assays in a common unitage, and for defining regulatory requirements in the field of mycoplasma testing.
Topics: DNA, Bacterial; Laboratories; Mycoplasma; Nucleic Acid Amplification Techniques; World Health Organization
PubMed: 26070671
DOI: 10.1128/AEM.01150-15 -
Applied Microbiology Sep 1969Except for Mycoplasma fermentans strain PG 18, single-cell suspensions of M. arthritidis, M. fermentans (ATCC 19989), M. hominis type 1, M. orale types 1 and 2, M....
Except for Mycoplasma fermentans strain PG 18, single-cell suspensions of M. arthritidis, M. fermentans (ATCC 19989), M. hominis type 1, M. orale types 1 and 2, M. pneumoniae, and M. salivarium were inactivated exponentially by ultraviolet (UV) irradiation, in contrast to broth cultures containing clusters of elementary bodies. The susceptibility of the mycoplasmas was unaffected by storage at 2-4 C and at -70 C, by sonication, and by filtration. The rate of inactivation was dependent on the intensity of the radiations but independent of the concentration of the cells. Therefore, single-cell suspensions of these mycoplasmas could be differentiated from aggregates of cells by exponential inactivation of the colony-forming units (CFU). By this criterion, the CFU of M. arthritidis in the exponential phase of growth consisted of single cells, in contrast to the other species in which the CFU contained two or more elementary bodies. Even though the cultures of M. fermentans (PG 18) were grown from single cells, they were not homogeneous in their susceptibility to UV light. Neither were cultures of M. arthritidis and M. orale type 1 grown from single cells which had survived irradiation.
Topics: Cell Aggregation; Cold Temperature; Culture Media; Filtration; Humans; Mouth; Mycoplasma; Pharynx; Radiation Effects; Ultraviolet Rays; Vibration
PubMed: 5373673
DOI: 10.1128/am.18.3.360-364.1969 -
Journal of Bacteriology Jun 1972Broth cultures of Acholeplasma laidlawii were fixed with various concentrations of cacodylate-buffered glutaraldehyde. The shape and ultrastructure of the organisms...
Broth cultures of Acholeplasma laidlawii were fixed with various concentrations of cacodylate-buffered glutaraldehyde. The shape and ultrastructure of the organisms varied with the osmolar concentration of the fixative. When the fixation mixture was hypertonic to the culture medium, ultrathin sections suggested that the cells had shrunk. Phosphate buffer, sodium chloride, or sucrose at comparable osmolaities had the same effect as sodium cacodylate. Glutaraldehyde itself also contributed to the osmotic effects of the fixation mixture but to a lesser extent than salts or sucrose, to which the cell membrane is impermeable. The osmolar concentration of the fixation mixture seemed of greater importance than pH in determining morphology. The mycoplasma was still susceptible to damage by high concentrations of cacodylate after fixation with 2.5% glutaraldehyde. The best procedure was to fix and wash the organism under conditions isotonic with the growth medium. These conditions were also satisfactory for a filamentous mycoplasma, Mycoplasma orale.
Topics: Acholeplasma laidlawii; Aldehydes; Arsenic; Bacteriological Techniques; Buffers; Cell Membrane Permeability; Indicators and Reagents; Isotonic Solutions; Micropore Filters; Microscopy, Electron; Mycoplasma; Osmolar Concentration; Phosphates; Sodium Chloride; Sucrose
PubMed: 4555408
DOI: 10.1128/jb.110.3.1154-1162.1972 -
Journal of Clinical Pathology Oct 1972Using a modified cell-free culture medium, a mycoplasma was isolated from sarcoid lymph nodes in two cases and from sarcoid skin lesions in four out of seven cases of...
Using a modified cell-free culture medium, a mycoplasma was isolated from sarcoid lymph nodes in two cases and from sarcoid skin lesions in four out of seven cases of chronic sarcoidosis. Growth inhibition tests showed that the isolates were related to Mycoplasma orale type 1. By the indirect haemagglutination method, 244 cases of definite or probable sarcoidosis, 160 patients with other diseases, and 355 blood donors were tested for antibodies against an isolated mycoplasma (strain 215-M). Titres [unk] 16 were found in 14% of the patients with sarcoidosis and in 8% of the patients with other diseases but only in 0.6% of the blood donors. The proportion of patients with high antibody titres among those with sarcoidosis and erythema nodosum was smaller (8%) than among those with other forms of sarcoidosis (17%). The role of the mycoplasmas isolated from sarcoid tissues remains obscure, but it is possible that these organisms are only an expression of altered immunity in sarcoidosis.
Topics: Adult; Antibodies, Bacterial; Biopsy; Blood Donors; Cell-Free System; Erythema Nodosum; Female; Hemagglutination Tests; Humans; Lymph Nodes; Male; Microscopy, Electron, Scanning; Middle Aged; Mycoplasma; Sarcoidosis; Skin
PubMed: 4646295
DOI: 10.1136/jcp.25.10.837 -
Journal of Bacteriology Nov 1986Mycoplasma salivarium produced citrulline, ammonia, and ATP from N-benzoylglycyl-L-arginine. The activity was inhibited by EDTA and was therefore concluded to be due to...
Mycoplasma salivarium produced citrulline, ammonia, and ATP from N-benzoylglycyl-L-arginine. The activity was inhibited by EDTA and was therefore concluded to be due to an arginine-specific carboxypeptidase. The activity was also found to exist in M. orale, M. buccale, M. faucium, and M. hominis.
Topics: Adenosine Triphosphate; Ammonia; Arginine; Carboxypeptidases; Citrulline; Humans; Lysine Carboxypeptidase; Mycoplasma; Mycoplasma pneumoniae
PubMed: 3096956
DOI: 10.1128/jb.168.2.1045-1047.1986 -
Journal of Bacteriology Jul 1981Acetate kinase activity was assayed in 13 mycoplasmas. Nine species exhibited the enzymic activity in the direction of either synthesis of acetylphosphate or adenosine... (Comparative Study)
Comparative Study
Acetate kinase activity was assayed in 13 mycoplasmas. Nine species exhibited the enzymic activity in the direction of either synthesis of acetylphosphate or adenosine triphosphate. On the other hand Mycoplasma orale, Mycoplasma arthritidis, Ureaplasma urealyticum (10 serotypes), and two strains of Anaeroplasma species exhibited only minimal levels of the enzymic activity. In these four species, the enzyme does not seem to play a key role in adenosine triphosphate formation.
Topics: Acetate Kinase; Acholeplasma; Adenosine Triphosphate; Mycoplasma; Phosphotransferases; Species Specificity; Ureaplasma
PubMed: 6263869
DOI: 10.1128/jb.147.1.271-273.1981 -
Infection and Immunity Nov 1977The capacity of various mycoplasma strains and species to induce lymphocyte transformation in vitro was studied. Of six strains of Mycoplasma pulmonis studied, five... (Comparative Study)
Comparative Study
The capacity of various mycoplasma strains and species to induce lymphocyte transformation in vitro was studied. Of six strains of Mycoplasma pulmonis studied, five displayed mitogenic activity with rat lymphocytes. Among those M. pulmonis strains, our MP15 isolate and the Negroni strain exhibited particularly potent mitogenic capacity. The murine mycoplasmas M. neurolyticum and M. arthritidis shared this mitogenicity for rat lymphocytes. However, the human mycoplasmas M. fermentans, M. pneumoniae, M. hominis, M. orale, and Acholeplasma laidlawii did not activate rat lymphocytes. Lymphocytes obtained from germfree rats were activated to the same extent as those from animals bred under conventional conditions. The mitogenic potency exhibited by mycoplasma was not restricted to infective microorganisms, and preparations of killed mycoplasma particles exerted an extensive lymphocyte transformation. The data show that the mitogenic activity of mycoplasmas is not confined to a single mycoplasma isolate and that it acts in a nonspecific manner.
Topics: Animals; Germ-Free Life; Lymphocyte Activation; Mitogens; Mycoplasma; Rats; Species Specificity
PubMed: 562852
DOI: 10.1128/iai.18.2.310-317.1977 -
Microbiology and Immunology 1992Various species of mycoplasmas were tested for their ability to induce cytokine production in human peripheral blood mononuclear cells (PBMC). Human PBMC were incubated...
Various species of mycoplasmas were tested for their ability to induce cytokine production in human peripheral blood mononuclear cells (PBMC). Human PBMC were incubated with Mycoplasma pneumoniae, M. hyorhinis, M. arginini, M. salivarium, M. orale, M. gallisepticum or A. laidlawii for 48 hr, and the activities of interleukin-1 beta (IL-1 beta), IL-2, IL-4, IL-6, tumor necrosis factor-alpha (TNF-alpha) and interferon (IFN) in the supernatants were determined by ELISA or bioassay. All mycoplasma species induced IL-1 beta, IL-6 and TNF-alpha, although IL-2 was induced only by M. pneumoniae. IFN was induced by 5 of the 7 species, and the IFN produced was antigenically confirmed to be mainly IFN-alpha. On the other hand, mycoplasma-stimulated cultures did not contain detectable amounts of IFN-beta and IL-4 activities. Furthermore, the cytokines were induced by mycoplasmal contaminating cells in human PBMC as well as by mycoplasma alone. These results suggest that many kinds of cytokines induced by mycoplasma contamination in cell culture affect immunological experiments in vitro.
Topics: Biological Assay; Cells, Cultured; Enzyme-Linked Immunosorbent Assay; Humans; Interferons; Interleukins; Leukocytes, Mononuclear; Mycoplasma; Tumor Necrosis Factor-alpha
PubMed: 1381037
DOI: 10.1111/j.1348-0421.1992.tb02048.x -
Applied Microbiology Jul 1972Five nonionic detergents (Tweens 20, 40, 60, and 80, and Triton WR-1339) were tested for their ability to inactivate four Mycoplasma species which are common...
Five nonionic detergents (Tweens 20, 40, 60, and 80, and Triton WR-1339) were tested for their ability to inactivate four Mycoplasma species which are common contaminants of animal cell cultures. Tween 20 was found to be the most effective, in that a concentration of 2.5 mg/ml completely inactivated cultures of M. hominis, M. hyorhinis, and Acholeplasma laidlawii within 1 hr and a culture of M. orale within 3 hr. The other detergents exhibited various degree of activity against the different mycoplasmas, with Triton WR-1339 being the least effective. The virucidal activity of the detergents was determined for six viruses. All four Tween compounds were highly virucidal for herpes simplex virus. Tween 20 also exhibited virucidal effects against vesicular stomatitis virus, California encephalitis virus, and Newcastle disease virus, and Tween 80 was found to be active against California encephalitis and Newcastle disease viruses. Detergent treatment procedures were effective in two instances in eliminating mycoplasma contaminants from virus preparations while the preparations retained most of the viral infectivity. The limitations of this technique for routine use are discussed.
Topics: Animals; Anti-Bacterial Agents; Anti-Infective Agents; Antiviral Agents; Bacteriological Techniques; Cell Line; Chick Embryo; Cricetinae; Culture Techniques; Drug Resistance, Microbial; Encephalitis Viruses; Humans; Kidney; Lung; Mycoplasma; Newcastle disease virus; Poliovirus; Simplexvirus; Species Specificity; Surface-Active Agents; Time Factors; Vaccinia virus; Vesicular stomatitis Indiana virus; Virus Cultivation
PubMed: 4341521
DOI: 10.1128/am.24.1.18-21.1972