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PubMed1994

Characterization of cytopathogenicity of aquarium seal mycoplasmas and seal finger mycoplasmas by light and scanning electron microscopy.

Two recent mycoplasma isolates (one from an aquarium seal and one from a patient with the clinical entity known as seal finger) have been evaluated for cytopathogenicity in tracheal explant cultures. Examinations were performed in direct comparison to Mycoplasma phocidae, an isolate from an epidemic of seal pneumonia along the New England coast (USA) in 1979-1980. The study revealed similar inhibitory effects on ciliated tracheal epithelial cells and clumping of cilia by attached mycoplasmas; no exfoliation of respiratory epithelial cells was observed. In addition, cytopathic effects caused by the mycoplasmas were distinguished from effects of aging in non-infected explants under long-term in-vitro cultivation conditions. The general meaning of mycoplasmas in seals is discussed in detail in this paper.

Animals↗
PubMed2006

Mycoplasma mycoides subsp. capri and Mycoplasma mycoides subsp. mycoides LC can be grouped into a single subspecies.

Mycoplasma mycoides subsp. capri and Mycoplasma mycoides subsp. mycoides LC can be combined into one taxon on the basis of several contributions on both DNA sequence and protein analyses reported in the literature. Moreover, for the differentiation and identification of mycoplasmas of the "mycoides cluster", we investigated the rpoB gene, encoding the beta-subunit of the RNA polymerase. A segment of 527 bp of the rpoB gene was amplified from 31 strains of ruminant mycoplasmas by PCR. The nucleotide sequences were determined and aligned, and accurate genetic relationships were calculated. Cluster analysis of rpoB DNA allowed species differentiation within the "mycoides cluster" and confirmed that M. mycoides subsp. capri and M. mycoides subsp. mycoides LC cannot be distinguished from each other. "Mycoplasma mycoides subsp. capri" is proposed as a common name for both subspecies.

Amino Acid Sequence↗
PubMed1978

Serologic studies of human genital mycoplasmas: distribution of titers of mycoplasmacidal antibody to Ureaplasma urealyticum and Mycoplasma hominis in pregnant women.

Titers of mycoplasmacidal antibody to the human genital mycoplasmas Ureaplasma urealyticum and Mycoplasma hominis were determined using genital isolates from pregnant patients as antigens and comparing these isolates with the 11 prototypic reference strains for U. urealyticum and the seven reference strains for M. hominis. Virtually all titers that were detected with use of the patient's own isolates were detected by the 11 reference strains of U. urealyticum and by the seven reference strains of M. hominis. Serologic surveys of pregnant women who harbored either or both mycoplasmas in vaginal cultures indicated that antibody to M. hominis was found more commonly than antibody to U. urealyticum. It was demonstrated that significant postpartum rises in titers of antibody to M. hominis were correlated with the presence of these mycoplasmas in genital cultures. Postpartum rises in titer of antibody were particularly likely to occur in women with low titers of mycoplasmacidal antibody in serum at the time of delivery. Approximately 88% of the women who were colonized with M. hominis showed significant changes in titer of antibody to M. hominis throughout an apparently normal pregnancy; only 40% of the women who were colonized with U. urealyticum showed such changes in titers to U. urealyticum. Statistical analysis showed that mean log titers of antibody to both mycoplasmas at the first prenatal visit were significantly associated with the number of pregnancies experienced by these women.

Antibodies, Bacterial↗
PubMed1997

Phylogenetic analysis of mycoplasmas based on Hsp70 sequences: cloning of the dnaK (hsp70) gene region of Mycoplasma capricolum.

A 5.0-kb region containing the hsp70 (dnaK) gene was cloned from Mycoplasma capricolum and sequenced. In addition to the hsp70 gene, this sequence region also contained the complete sequences for the grpE and orfA genes and partial sequences for the clpB and dnaJ genes. The order of the above gene sequences in the cloned fragment was found to be clpB-orfA-grpE-hsp70-dnaJ, which is similar to the order seen in various other gram-positive groups of bacteria. The Hsp70 homologs from two mycoplasma species, Mycoplasma capricolum and Mycoplasma genitalium, contain a number of sequence signatures, including the absence of a large insert in the N-terminal quadrant, that are characteristics of the homologs from gram-positive bacteria and archaebacteria. A detailed phylogenetic analysis based on Hsp70 sequences was also performed. In neighbor-joining and parsimony trees based on Hsp70 sequences, both mycoplasma species branched with the low-G + C-content gram-positive group of bacteria (e.g., Lactobacillus and Erysipelothrix species) in 87% and 96% of the bootstrap replicates, respectively, indicating their close evolutionary relationship to this group. The phylogenetic trees based on Hsp70 sequences show a polyphyletic branching of archaebacteria with the gram-postive species, which is statistically strongly favored.

Amino Acid Sequence↗
PubMed1978

The effect of pneumonia induced in mice with Mycoplasma pulmonis on resistance to subsequent bacterial infection and the effect of a respiratory infection with Sendai virus on the resistance of mice to Mycoplasma pulmonis.

The effect of pneumonia induced by Mycoplasma pulmonis in mice on the resistance of the lung to additional bacterial infection was examined. The effect of pneumonia induced by Sendai virus on the resistance of mice to M. pulmonis was also investigated and compared with the effect of Sendai virus on resistance to Staphylococcus aureus. Sendai virus infection decreased subsequent resistance to M. pulmonis in proportion to the virus dose. Decreased resistance to subsequent S. aureus and M. pulmonis infection was greatest at about the same time after inoculation of virus and was related to virus-induced lesions. Besides affecting the resistance of mice to subsequent mycoplasma infection, Sendai virus could enhance an existing mycoplasma infection. Pneumonia induced by M. pulmonis did not decrease resistance to subsequent bacterial infection. The mechanism whereby Sendai virus decreases host resistance is therefore similar for bacteria and mycoplasmas, but pneumonia induced by mycoplasmas does not have the same effect.

Animals↗
PubMed1976

Interaction of Mycoplasma dispar and Mycoplasma agalactiae subsp. bovis with bovine alveolar macrophages and bovine lacteal polymorphonuclear leukocytes.

Mycoplasma dispar and Mycoplasma agalactiae subsp. bovis survived or grew in cultures of bovine lacteal polymorphonuclear leukocytes or bovine alveolar macrophages. In the presence of specific bovine antibody, macrophages and polymorphonuclear leukocytes appeared to kill both species of mycoplasma. Specific rabbit antisera also promoted the killing of these mycoplasmas by bovine macrophages but had no demonstrable activity for bovine polymorphonuclear leukocytes. It is suggested that phagocytosis of these mycoplasmas by bovine cells occurs only in the presence of specific antibody. The experiments also indicate that differences exist between bovine polymorphonuclear leukocytes and macrophages with regard to their receptor sites for immunoglobulins.

Animals↗
PubMed1980

Mycoplasma-dependent activation of normal mouse lymphocytes: requirement for functional T lymphocytes in the cytotoxicity reaction mediated by Mycoplasma arthritidis.

Syngeneic and allogeneic target cells were killed in the presence of CBA mouse lymphocytes and viable Mycoplasma arthritidis. Medium supplementation had no effect on the response. Nonviable M. arthritidis was also capable of stimulating lymphocytotoxicity, although to a much lesser extent. Cytotoxicity was shown to be largely dependent upon the lymphocytes, since lymphocytes preincubated with mycoplasmas and treated to remove remaining organisms were highly toxic to target cells, whereas supernatants prepared from lymphocyte/mycoplasma mixtures exhibited minimal effects. A 6-h exposure of lymphocytes to mycoplasmas at a ratio of 100:1 was sufficient for commitment to target cell killing. Functional lymphocytes were required for the reaction, since gamma-irradiated lymphocytes did not develop cytotoxic potential despite the fact that the mycoplasmas replicated equally well in the presence of these and untreated lymphocytes. Furthermore, lymphocytes already activated with mycoplasmas lost cytotoxic potential after disruption. The kinetics and degree of lymphocytotoxicity induced by M. arthritidis and phytohemagglutinin toward 51Cr-labeled syngeneic fibroblasts were similar. Removal of most B cells and other adherent cells by column separation did not abrogate the cytotoxic effect. Lymphocyte suspensions treated with anti-Thy 1 antiserum and complement exhibited a marked decrease in their cytotoxic potential when added to labeled target cells in the presence of M. arthritidis. We conclude that the cytotoxic reaction is dependent upon the T-lymphocyte subpopulation.

Animals↗
PubMed1970

Heterogeneity among strains of Mycoplasma granularum and identification of Mycoplasma hyosynoviae, sp. n.

Twelve filtrable, pleomorphic organisms isolated from swine joints and respiratory tracts had typical colonial and microscopic characteristics of mycoplasmas. They resisted penicillin and did not revert to cell wall-producing bacterial forms in media devoid of bacterial inhibitors. The morphological and growth characteristics of these mycoplasmas were similar to those described previously for Mycoplasma granularum. However, a new name, M. hyosynoviae, is proposed for them since they differed biologically, serologically, and electrophoretically from the prototype strain of M. granularum. M. hyosynoviae required sterols, was stimulated by gastric mucin, and metabolized arginine; however, it did not metabolize urea, ferment glucose, or reduce tetrazolium. The organism produced "film and spots" on horse serum-supplemented medium and produced alpha hemolysis of guinea pig and sheep erythrocytes; however, it did not digest serum, produce phosphatase, or hemadsorb guinea pig or swine erythrocytes. M. hyosynoviae was distinguished from three other swine mycoplasmas, M. granularum, M. hyorhinis, and M. laidlawii, by means of acrylamide gel electrophoresis, growth inhibition, metabolic inhibition, and immunodiffusion techniques. It was also serologically and electrophoretically distinct from 13 additional non-swine mycoplasmas which require sterols and metabolize arginine.

Acrylates↗
PubMed2000

Construction and use of derivatives of transposon Tn4001 that function in Mycoplasma pulmonis and Mycoplasma arthritidis.

Previous attempts to introduce transposon Tn4001 into Mycoplasma pulmonis and Mycoplasma arthritidis have not been successful, possibly due to functional failure of the transposon's gentamicin resistance determinant. Tn4001C and Tn4001T were constructed, respectively, by insertion of a chloramphenicol acetyltransferase gene and the tetM tetracycline resistance determinant into Tn4001. Both Tn4001C and Tn4001T transposed in M. pulmonis, and Tn4001T transposed in M. arthritidis. The incorporation of a Tn4001T derivative that contained lacZ into either Mycoplasma species resulted in transformants with readily detectable LacZ activity. Tn4001T may be of general utility for use as a mycoplasma cloning vehicle because tetM functions in all species of Mycoplasma examined thus far.

Chloramphenicol O-Acetyltransferase↗
PubMed1969

Characterization of a newly identified mycoplasma (Mycoplasma orale type 3) from the human oropharynx.

Six mycoplasma strains, isolated under anaerobic conditions from the human oropharynx, were studied by biologic and serologic means. The strains produced nippled colonies with weak hemolytic activity for guinea pig erythrocytes on agar medium. In addition, the strains metabolized arginine with a concomitant alkaline shift in the pH of the medium but did not produce a pH shift when grown in the presence of glucose or urea. The strains failed to reduce 2-3-5 triphenyl tetrazolium and were inhibited by 0.001% methylene blue. In addition, they required fresh yeast extract for growth. When compared by several serologic methods, the strains were found to be related to each other but distinct from 23 serotypes of human, animal, and avian origin. However, one-way serologic relationships between one of the new strains and Mycoplasma orale type 1 and M. salivarium were observed when they were tested by complement fixation. Furthermore, partial relationship of one of the new strains to all of the arginine-utilizing mycoplasma species of human origin was demonstrated with the agar gel diffusion technique. Thus, the new strains appear to constitute a new mycoplasma species, for which the name M. orale type 3 is tentatively proposed. M. orale type 3 accounted for 1.4% of 437 mycoplasma isolates from the oropharynx of adults. The new species probably is a rare member of the normal mycoplasmal flora of man.

Complement Fixation Tests↗
PubMed1975

Some recommendations concerning primary isolation of Mycoplasma suipneumoniae and Mycoplasma flocculare a survey.

Two mycoplasma species of the porcine respiratory tract: Mycoplasma suipneumoniae and Mycoplasma flocculare, have been notoriously difficult to cultivate. In the present paper a description is given of a new medium with which primary isolation of these organisms is usually successful. The basal medium is made from commercial dehydrated products. Pig serum is added and phenol red used as pH indicator. Contrary to what is customary in the preparation of mycoplasma media, various inorganic salts (Hank's balanced salt solution) are included and penicillin-G replaced as a bacteriostatic by bacitracin and meticillin. The volume of water is adjusted so as to give isotonia. Various additives often recommended for mycoplasma cultivation have been examined for growth promoting effect; apparently, however, they were all without effect. Working procedures for primary isolation trials are briefly described.

Animals↗
PubMed2004

[Comparison of polymerase chain reaction assay and Mycoplasma IST 2 test with culture for detection of infections caused by Ureaplasma urealyticum and Mycoplasma hominis].

The polymerase chain reaction (PCR) technique and commercial Mycoplasma IST 2 test were compared with culture for the detection of U. urealyticum and M. hominis in 173 clinical samples obtained from patients without clinical symptoms from genito-urinary tract. The presence of U. urealyticum was diagnosed by culture in 24 samples, by PCR in 33 samples and by Mycoplasma IST 2 test in 39 samples. The presence of M. hominis was diagnosed in 26 samples only by Mycoplasma IST 2 test--culture and PCR were negative. The study showed the excellent sensitivity (100%) and good specificity (appropriately 94.0% and 90.0%) for U. urealyticum in PCR and Mycoplasma IST 2 test. The discrepancy of results obtained in Mycoplasma IST 2 test and culture as well as in PCR may suggest the over sensitivity of the commercial test for detection of M. hominis.

Bacteriological Techniques↗
PubMed2006

Characterisation of protein and antigen variability among Mycoplasma mycoides subsp. mycoides (LC) and Mycoplasma agalactiae field strains by SDS-PAGE and immunoblotting.

Mycoplasma mycoides subsp. mycoides (LC) (Mmm LC) and Mycoplasma agalactiae are the most important mycoplasma species involved in the contagious agalactia syndrome. A total of 25 field strains from Spain and the two type strains were analysed by SDS-PAGE and immunoblotting. Two polyclonal antisera (PAbs) raised against a pool of strains of each mycoplasma species were used. The results revealed a high degree of protein variability among the field strains. The type strain of Mmm LC appeared to be representative of the field strains of this species, whereas this was not the case with the M. agalactiae type strain. Whereas M. agalactiae is known to possess a gene family regulating surface antigen diversity, there is a need to study the mechanisms used byMmm LC to generate antigenic variability in more detail.

Animals↗
PubMed2004

Aerosolization of Mycoplasma synoviae compared with Mycoplasma gallisepticum and Enterococcus faecalis.

In order to study the airborne transmission of an arthropathic strain of Mycoplasma synoviae, preliminary aerosol experiments were performed. They were conducted in duplicate in an empty isolator (1.3 m3) to assess the yield and viability of M. synoviae with time compared with Mycoplasma gallisepticum and Enterococcus faecalis. After aerosol generation air samples were taken with two different devices using gelatine or cellulose nitrate filters. There was no difference between the devices, but cellulose nitrate filters yielded very low bacterial counts. The aerosolized dose per isolator for M. synoviae was 3.4 x 10(10) colony-forming units (cfu), for M. gallisepticum was 2.6 x 10(10) cfu and for E. faecalis was 3 x 10(10) cfu. Immediately after aerosolization, concentrations of about 10(6) to 10(7) cfu/m3, 10(7) to 10(8) cfu/m3 and 10(8) to 10(9) cfu/m3 air of M. synoviae, M. gallisepticum and E. faecalis were found, respectively. At 25 min M. synoviae concentrations dropped below the detection level (<4 x 10(4) cfu), while 10(5) to 10(6) and 10(8) to 10(9) cfu were found for M. gallisepticum and E. faecalis, respectively. The average M. synoviae concentration during the experiment was estimated at 10(2) to 10(3) cfu/l. The M. gallisepticum and E. faecalis aerosol generated an average of approximately 10(3) to 10(4) cfu/l air and 10(5) to 10(6) cfu/l air, respectively. Thus mycoplasma and E. faecalis aerosols were successfully generated despite considerable initial loss as measured by culture. The loss was greater in the mycoplasma aerosols, especially those of M. synoviae.

Aerosols↗
PubMed2006

Morphology of human Fallopian tubes after infection with Mycoplasma genitalium and Mycoplasma hominis--in vitro organ culture study.

BACKGROUND: Female infertility can be caused by scarring and occlusion of the Fallopian tubes. Sexually transmitted bacteria can damage the delicate epithelial layer of human Fallopian tubes (HFT). Genital mycoplasmas are associated with human reproductive failure. Yet, there is not enough evidence that mycoplasmas can cause tubal factor infertility. We analysed the effects of infections with Mycoplasma hominis and Mycoplasma genitalium on the HFT epithelium and compared them with the effects of infections with genital pathogens: Chlamydia trachomatis and Neisseria gonorrhoeae. METHODS: We used an in vitro model in which pieces of normal HFT were infected with different bacteria, and the outcome of the infections was analysed by scanning electron microscopy (SEM) and confocal microscopy. RESULTS: The presence of M. hominis did not cause any morphological changes of the epithelium of HFT. Noticeable changes in the morphology of the ciliated cells were observed in M. genitalium-infected tissue. Five days post-infection, the cilia were abnormally swollen and some of the ciliated cells fell off the epithelium. These effects could be inhibited by pre-incubation of M. genitalium with antibody directed against the C-terminal part of the adhesion protein MgPa before infection of HFT organ culture. CONCLUSION: We have shown that the presence of M. genitalium, but not M. hominis, in the HFT organ culture affected the epithelium and resulted in cilia damage. The effect of infection with M. genitalium on the HFT was, however, very moderate when compared with the extensive damage of the epithelium caused by N. gonorrhoeae or C. trachomatis.

Bacterial Adhesion↗
PubMed2005

Suppression subtractive hybridization as a basis to assess Mycoplasma agalactiae and Mycoplasma bovis genomic diversity and species-specific sequences.

The phylogenically related Mycoplasma agalactiae and Mycoplasma bovis species are two ruminant pathogens difficult to differentiate and for which a limited amount of sequence data are available. To assess the degree of genomic diversity existing between and within these mycoplasma species, sets of DNA fragments specific for M. bovis type-strain PG45 or for M. agalactiae type-strain PG2 were isolated by suppression subtractive hybridization and used as probes on a panel of M. agalactiae and M. bovis field isolates. Results indicated that approximately 70 % of the DNA fragments specific to one or the other type strain are represented in all field isolates of the corresponding species. Only one M. bovis isolate, which was first classified as M. agalactiae, reacted with 15 % of the PG2-specific probes, while several M. agalactiae isolates reacted with 15 % of the PG45-specific probes. Sequence analyses indicated that most of the genomic diversity observed within one species is related to ORFs with (i) no homologies to proteins recorded in the databases or (ii) homologies to proteins encoded by restriction modification systems. Reminiscent of gene transfer as a means for genomic diversity, a PG45-specific DNA fragment with significant homologies to a central protein of an integrative conjugative element of Mycoplasma fermentans (ICEF) was found in most M. bovis field isolates and in a few M. agalactiae isolates. Finally, sequences encoding part of DNA polymerase III were found in both sets of M. agalactiae- and M. bovis-specific DNA fragments and were used to design a species-specific PCR assay for the identification and differentiation of M. agalactiae and M. bovis.

Animals↗
PubMed2003

Rapid detection of Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma parvum, and Ureaplasma urealyticum organisms in genitourinary samples by PCR-microtiter plate hybridization assay.

We present a method for detecting the presence of Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma parvum, and Ureaplasma urealyticum organisms, which are thought to be associated with nongonococcal urethritis (NGU) and other genitourinary infections, in clinical samples. This method consists of PCR amplification of a part of the 16S rRNA gene followed by 96-well microtiter plate hybridization assay using four species-specific capture probes to detect the targets. To test the efficacy of this method, we applied it to the detection of the four species in the urine of patients with NGU. There were no cross-reactions with other human mycoplasmas or ureaplasmas, and the PCR-microtiter plate hybridization assay detected as few as 10 copies of the 16S rRNA gene of each of the four species. Based on these results, this PCR-microtiter plate hybridization assay can be considered an effective tool for the diagnosis of genitourinary infections with mycoplasmas or ureaplasmas.

Bacteriological Techniques↗
PubMed1993

Species-specific oligonucleotide probes complementary to 16S rRNA of Mycoplasma gallisepticum and Mycoplasma synoviae.

Mycoplasma gallisepticum and M synoviae are important avian pathogens causing respiratory diseases which result in great economic losses in poultry farming. Two oligonucleotide probes, complementary to the variable region V8 of 16S rRNA from the avian mycoplasmas M gallisepticum and M synoviae have, therefore, been designed and used in direct filter hybridisation experiments. Both probes gave strong hybridisation signals with their homologous targets, whereas no cross-hybridisations were obtained with any of the other avian mycoplasmas tested. It was possible to detect 2-3 x 10(4) mycoplasma organisms by direct filter hybridisation experiments with radiolabelled probes. The probes were also used to analyse several laboratory strains and field isolates of M gallisepticum and M synoviae with complete agreement between the probe technique and the other methods used for species determination. Atypical M gallisepticum strains also gave strong hybridisation signals with the M gallisepticum specific probe.

Animals↗