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PubMed1992

Specificity of oligonucleotide probes complementary to evolutionarily variable regions of 16S rRNA from Mycoplasma hyopneumoniae and Mycoplasma hyorhinis.

Mycoplasma is the common name for the smallest free-living microorganisms, the Mollicutes. Mycoplasma hyopneumoniae is of great importance in veterinary medicine, causing enzootic pneumonia in pigs. M hyorhinis can cause polyserositis and may cause pneumonia in piglets. Oligonucleotides complementary to variable regions of 16S rRNA from these mycoplasmas were designed and used as probes for detection and identification of these mycoplasmas. The probe complementary to 16S rRNA of M hyorhinis gave a very weak cross-hybridisation with M hyosynoviae in filter hybridisation experiments, but not with any of the other porcine mycoplasmas tested. Three oligonucleotide probes complementary to M hyopneumoniae 16S rRNA were tested. One of the probes (Mhp6/30) was found to be specific to M hyopneumoniae, but the other two gave cross-hybridisation with M flocculare. Using the Mhp6/30 probe in direct filter hybridisation experiments, it proved possible to detect M hyopneumoniae in lung biopsies from experimentally infected pigs.

Animals↗
PubMed2003

Presence of Mycoplasma haemofelis, Mycoplasma haemominutum and piroplasmids in cats from southern Europe: a molecular study.

Clinical symptoms produced by Mycoplasma spp. and piroplasmids in cats are sometimes similar. Diagnosis of these pathogens is difficult by microscopic procedures and molecular methods have been used as an alternative. We present in this work, the development of new molecular procedures for diagnosis of the aforementioned organisms, together with a molecular characterization of isolates found in southern European cats.A single PCR-RFLP procedure was designed for diagnosis of Mycoplasma spp. and a seminested PCR-RFLP was designed for diagnosis of piroplasmids. The 16S or 18S rRNA genes of isolates found in clinical samples were partially sequenced in all positive cases. Mycoplasma spp. was detected in 9 (30%) out of 30 symptomatic cats from Spain. Sequencing indicated that 66.6% of these isolates can be ascribed to Mycoplasma haemofelis and only 33.3% to Mycoplasma haemominutum. Partial 16S rRNA sequences obtained in Spanish isolates were very similar to those previously published from the UK and the USA. The presence of piroplasmids (Babesia and Theileria spp.) was studied in 16 cats from Spain (n=13) and Portugal (n=3). Animals analyzed were 10 cats with immunosuppressive viral infection (either FeLV or FIV), 5 asymptomatic cats and 1 cat with Babesia-compatible symptoms. Asymptomatic cats were all PCR-negative. Partial sequencing of 18S rRNA gene demonstrated that the Babesia-symptomatic cat was infected with Babesia canis canis whereas 3 (30%) out of the 10 cats with immunosuppressive viral infection were coinfected with piroplasmids (1 with B. canis canis, 1 with Theileria annae, and 1 with B. canis canis and T. annae both).

Animals↗
PubMed1999

Comparative analysis of the lppA locus in Mycoplasma capricolum subsp. capricolum and Mycoplasma capricolum subsp. capripneumoniae.

The lppA gene, encoding the lipoprotein named LppA[Mcaca] was characterised in Mycoplasma capricolum subsp. capricolum. It encodes a lipoprotein with an apparent molecular mass of 57 kDa as determined by SDS-PAGE. Using antibodies directed against recombinant LppA[Mcaca], we showed the expression of this lipoprotein in all M. capricolum subsp. capricolum by immunoblot analysis. The serum did not cross-react with other members of the Mycoplasma mycoides cluster, hence showing that LppA[Mcaca] was antigenically specific to M. capricolum subsp. capricolum. The lppA gene was conserved within the subspecies and was used for the development of a specific PCR assay for the identification of M. capricolum subsp. capricolum. The taxonomically related Mycoplasma capricolum subsp. capripneumoniae (F38) was found to contain an lppA-pseudo-gene. It showed high similarity to functional lppA genes of other mycoplasmas in the M. mycoides cluster. However, it contained interrupted open reading frames. Moreover, the nucleotide sequence of the lppA pseudo-genes in different strains of M. capricolum subsp. capripneumoniae were quite variable. Interestingly, the lppA pseudo-gene had a size similar to that of the functional lppA genes of other mycoplasmas of the M. mycoides cluster and occupied the same genomic location as the latter ones in the vicinity of the mtlD genes. This study showed that all members of the M. mycoides cluster contain each a species-, subspecies- respectively type- specific lppA gene analogue which encodes a lipoprotein that has structural and functional relationship to the surface lipoprotein LppA [MmymySC], previously named P72, of M. mycoides subsp mycoides SC, with the exception of M. capricolum subsp. capripneumoniae which seems not to express an LppA analogue.

Animals↗
PubMed2001

Immunomodulatory properties of Mycoplasma pulmonis. III. Lymphocyte stimulation and cytokine production by Mycoplasma pulmonis products.

Experiments are presented that were performed in order to understand the mechanisms causing these effects on the immune system. Mitogenic effects of Mycoplasma membranes on mouse spleen cells were shown using M. capricolum. The observed mitogenic activity is proportional to the amount of membranes used, as measured by protein content. Separation of T and B cells was performed by two techniques, the anti-Thyl.2 plus complement method and the Dynabead technique. Using the former technique, it was shown that removal of T cells markedly reduced effects of stimulation by mycoplasma membranes, but did not abolish it. The separated cells were still stimulated by PHA, indicating that the preparation still contained T cells. Furthermore, removal of T cells preferentially reduced the PHA response over that of mycoplasma membranes, indicating that mycoplasma membranes stimulate both B and T lymphocytes. The Dynabead system was found to be the more efficient separation technique, and by using it we were able to make the following observations. Inactivated Mp, membranes and culture supernatant stimulated B cells, whereas T cells were only slightly stimulated by inactivated Mp and membranes. There was an increase in proliferation when T cells were incubated with adherent cells from peripheral blood. Finally, we showed that spleen cells from infected animals produce more IL-4 and less IFN-gamma than cells from non-infected animals when stimulated with membranes, inactivated Mp, culture supernatant or phytohemagglutinin. Altogether, these results show that lymphocytes from Mycoplasma-infected animals are directly affected and this effect is probably due to superantigen-like molecules from M. pulmonis.

Adjuvants, Immunologic↗
PubMed1998

Phylogenetic position of rare human mycoplasmas, Mycoplasma faucium, M. buccale, M. primatum and M. spermatophilum, based on 16S rRNA gene sequences.

The nucleotide sequence of the 16S rRNA genes of four rare human mycoplasma species, Mycoplasma faucium, M. buccale, M. primatum and M. spermatophilum, were partially sequenced and compared to published rRNA genes of mycoplasmas to determine their position in the Mollicutes phylogenetic tree. Nucleotide sequence motif and overall similarities allowed positioning of these mycoplasmas in the hominis phylogenetic group, as defined by Weisburg et al. [Weisburg, W. G., Tully, J. G., Rose, D. L. & 9 other authors (1989). J Bacteriol 171, 6455-6467]. Furthermore, these mycoplasmas could be clustered into two different subdivisions of the hominis group: (i) M. faucium and M. buccale were found to be included in the M. fermentans subdivision, and (ii) M. primatum and M. spermatophilum were included in the M. hominis one. Variable regions of the 16S rRNA genes were used to determine specific PCR primers to detect and identify M. faucium.

Genes, Bacterial↗
PubMed2000

Comparison of the 16S-23S rRNA intergenic spacer regions among strains of the Mycoplasma mycoides cluster, and reassessment of the taxonomic position of Mycoplasma sp. bovine group 7.

Nucleotide sequence analysis of the 16S-23S rRNA intergenic spacer regions of six type or reference strains belonging to the Mycoplasma mycoides cluster and of Mycoplasma putrefaciens suggested the presence of two subclusters. One subcluster comprised M. mycoides subsp. mycoides small colony (SC) type, M. mycoides subsp. mycoides large colony (LC) type and M. mycoides subsp. capri, whereas the second subcluster comprised Mycoplasma capricolum subsp. capricolum, M. capricolum subsp. capripneumoniae and Mycoplasma sp. bovine group 7. The type strains from M. mycoides subsp. mycoides SC and M. mycoides subsp. capri had identical spacer sequences. The existence of two subclusters was supported by predicted secondary structures of the analysed region. The nucleotide variations in the loop domains of the secondary structures might be a useful genetic marker to distinguish between the two subclusters. The secondary structure differences delineated the differences between the two subclusters more clearly than the nucleotide sequence alignments, which only showed a small number of differences, and some of these were common to both clusters. The data also provided evidence in favour of a reclassification of Mycoplasma sp. bovine group 7 as another subspecies of M. capricolum.

Animals↗
PubMed2002

High prevalence of Mycoplasma infections among European chronic fatigue syndrome patients. Examination of four Mycoplasma species in blood of chronic fatigue syndrome patients.

Prevalence of Mycoplasma species infections in chronic fatigue syndrome (CFS) has been extensively reported in the scientific literature. However, all previous reports highlighted the presence of Mycoplasmas in American patients. In this prospective study, the presence of Mycoplasma fermentans, M. penetrans, M. pneumoniae and M. hominis in the blood of 261 European CFS patients and 36 healthy volunteers was examined using forensic polymerase chain reaction. One hundred and seventy-nine (68.6%) patients were infected by at least one species of Mycoplasma, compared to two out of 36 (5.6%) in the control sample (P<0.001). Among Mycoplasma-infected patients, M. hominis was the most frequently observed infection (n=96; 36.8% of the overall sample), followed by M. pneumoniae and M. fermentans infections (equal frequencies; n=67; 25.7%). M. penetrans infections were not found. Multiple mycoplasmal infections were detected in 45 patients (17.2%). Compared to American CFS patients (M. pneumoniae>M. hominis>M. penetrans), a slightly different pattern of mycoplasmal infections was found in European CFS patients (M. hominis>M. pneumoniae, M. fermentansz.Gt;M. penetrans).

Adolescent↗
PubMed2005

[Evaluation of ELISA kits for detection of Mycoplasma pneumoniae--specific IgG, IgA, IgM antibodies on the diagnosis of Mycoplasma pneumoniae infection in children].

A retrospective study was conducted to evaluate the utility of Mycoplasma pneumoniae IgG (quantitative), IgA (quantitative), IgM (qualitative) ELISA kits (Medac Diagnostika, Germany) for the diagnosis of M. pneumoniae pneumonia in children under 16 years of age. This study included a total of 159 serum samples from 113 patients with acute respiratory diseases such as bronchitis, pneumonia, which were classified into three groups according to the results of a particle agglutination (PA) test as a reference method, that is, Group I (Mycoplasma-definite cases): Group I-a (paired 52 samples from 26 cases); a four-fold or greater rise of antibody from an acute phase PA titer of < or = 1:80, Group I-b (paired 12 samples from 6 cases); a four-fold or greater rise of antibody from an acute phase PA titer of > or = 1:160, Group I-c (48 samples from 38 cases); a single high PA titer of > or = 1:640 either or both in acute or convalescent serum, Group II (Mycoplasma-probable cases, 18 samples from 17 cases): a PA titer of 1:160 or 320 was observed either or both in acute or convalescent serum, but the above serological criteria for Group I were not fulfilled, Group III (non-cases, 29 samples from 26 cases): a PA titer of any sample was < or = 1:80. The ELISA tests were performed according to the supplier's recommendations, and the results were classified according to the interpretation provided by the supplier: Early stage of infection (category 1,2), Acute- (3,4,5), Current- (6), Past- (7), and No-infection (8). The day of onset of fever (defined as a body temperature of > or = 37.5 degrees Celsius) was denoted as day 0. As a result from Group I, the category initially observed following the onset of fever was category 8 (triple negative), and the predominance of category 8 was replaced by category 1 (IgM solely positive) after day 4, followed by a shift of predominance to category 4 (IgM and IgG double positive) or 5 (triple positive) after day 10 or later. Specifically, category 1 was rather exclusively observed before day 21 following the onset of fever. These results suggest that category 1, when observed, is a useful marker of acute infection by Mycoplasma pneumoniae in children because it appears early in the acute phase and no longer observed beyond the convalescent phase. On the other hand, significance of detecting IgA antibody, which must be important for adults, was not remarkable in our study. Five samples in group II and 3 samples in group III fell into category 1. Whether or not such cases, in the absence of significant PA titers, can be taken actually as mycoplasmal infection remains to be clear. This study validated the utility of this ELISA methodology in terms of the acute phase diagnosis using a single point serum sample for Mycoplasma pneumoniae infection specifically in children.

Adolescent↗
PubMed1984

Serological cross-reactions between Mycoplasma genitalium and Mycoplasma pneumoniae.

The recently discovered mycoplasma species Mycoplasma genitalium was isolated from urethral specimens from men with nongonococcal urethritis (Tully et al., Lancet i:1288-1291, 1981). In a previous report (K. Lind, Lancet ii:1158-1159, 1982), prominent serological cross-reactions were demonstrated between this mycoplasma and M. pneumoniae. In the present study, the two mycoplasma species were compared more extensively. In classical mycoplasma medium without thallium acetate, M. genitalium grew more slowly than M. pneumoniae did but finally formed similar amounts of acetic acid and lactic acid from glucose. Although their colonies on solid medium were indistinguishable, transmission electron microscopy showed that the flask-formed cells of M. genitalium (especially their necks) were shorter than those of M. pneumoniae. The two species were distinct since DNA hybridization showed only 1.8% homology in base sequences, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed significantly different profiles of the two strains. However, considerable similarities were found in their antigenic reactions in various serological tests. The presence of common or closely related antigens was demonstrated in the two species with rabbit immune sera in complement fixation test with chloroform-methanol-extracted antigens by an indirect immunofluorescence test on microcolonies, and by metabolism inhibition and growth inhibition tests. Cross-reactions were also demonstrated by crossed immunoelectrophoresis. The role of M. genitalium as a human pathogen in the genital tract has not been assessed. If serological tests are to be used in this assessment, caution must be exercised due to the extensive cross-reactions demonstrated. Some of the species-specific antigens which we have demonstrated would be appropriate for use in such tests and would help to circumvent problems caused by cross-reactions.

Animals↗
PubMed2002

Genital mycoplasmas, including Mycoplasma genitalium, as sexually transmitted agents.

Mycoplasmas are the smallest free-living organisms, widespread in nature. Several mycoplasma species have been isolated from humans. For 6 of them: Mycoplasma hominis, Ureaplasma urealyticum, M. primatum, M. genitalium, M. spermatophilum and M. penetrans, the genital tract is the main site of colonization. This review is concentrated on the role of mycoplasmas as sexually transmitted agents, with the emphasis to M. genitalium infections. M. hominis and U. urealyticum are isolated from the genital tract of healthy men and women with considerable frequency. The biological features (attachment properties, possible intracellular location) and experimental inoculation studies of M. genitalium indicate that this mycoplasma has pathogenic potential. Data from case-control studies, looking at men with non-gonococcal urethritis and women with cervicitis, have revealed that M. genitalium behave similarly to Chlamydia trachomatis and have revealed that carriage of M. genitalium and C. trachomatis is usually independent of one another. M. genitalium could be considered as a potential cause of sexually transmitted urethritis in men, including men with persistent or recurrent urethritis. More studies are expected to ascertain the role of M. genitalium in the female genital tract. Evidence-based data are needed to decide whether current non-gonococcal infection treatment principles are applicable or not for M. genitalium infections.

Female↗
PubMed2000

Demonstration of Mycoplasma capricolum subsp. Capripneumoniae and Mycoplasma mycoides subsp. mycoides, small colony type in outbreaks of caprine pleuropneumonia in eastern Tanzania.

An outbreak of caprine pleuropneumonia involving about 1200 goats in the Coast and Morogoro regions of eastern Tanzania is reported. The major clinical findings were severe respiratory distress, fever, mucopurulent nasal discharge and high mortality involving all age groups and both sexes of goats. The morbidity and mortality rates were 45%-90% and 14%-50%, respectively. The principal pathological lesions were confined to the thoracic cavity and comprised hydrothorax and serofibrinous pleuropneumonia. The histopathological features consisted of a necrotizing fibrinous pleuropneumonia characterized by different degrees of vasculitis, and fibrinocellular exudation into the alveolar septae and lumina, and into interlobular septae and pleura. Mycoplasma capricolum subsp. capripneumoniae, Mycoplasma mycoides subsp. mycoides, Small Colony type Mycoplasma ovipneumoniae and Mycoplasma arginini were isolated from some of the examined goats including a case with a sequestrum which yielded Mycoplasma mycoides subsp. mycoides, Small Colony type. This work reports the first description of an outbreak of caprine pleuropneumonia in Tanzania in which M. capripneumoniae and M. mycoides subsp. mycoides, Small Colony type were concurrently isolated.

Animals↗
PubMed1977

Mycoplasma and mycoplasma mastitis.

Mastitis due to mycoplasma has been reported sporadically from several countries in Europe, Australia, Israel, New Zealand, and many states in the United States. Most reported occurrences are due to Mycoplasma bovis, but 5 other mycoplasmas are reported to cause mastitis. A total of 5 species of mycoplasma have been isolated from cows with mastitis in California. Therapy trials with M bovis infections have not been encouraging. Recovery is slow, and shedding of mycoplasma into milk of apparently recovered cows for an indefinite period is common.

Animals↗
PubMedDate not supplied

The genetic relation between Mycoplasma hominis and other Mycoplasma species.

Purified preparations of DNA from five Mycoplasma species of human origin, including Mycoplasma hominis, were analyzed for homology. In general, very low-level homology (less than 0.5%) was found, but two pairs of species showed greater homology: M. hominis and Mycoplasma salivarium were related by a 2.6% homology, Mycoplasma pneumoniae and Mycoplasma genitalium (a proposed new species) were related by a 1.8% homology. These results indicate that the species involved are distinct but distantly related to each other.

Adult↗
PubMed2006

Detection of Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma urealyticum, and Ureaplasma parvum DNAs in urine from asymptomatic healthy young Japanese men.

The aim of this study was to estimate the detection rates of Mycoplasma and Ureaplasma, which are presumptive causes of sexually transmitted diseases (STDs), in young men in Sapporo, Japan. In addition, we examined the associations among Chlamydia trachomatis, Mycoplasma, and Ureaplasma. A survey of 100 asymptomatic healthy male volunteers was carried out. C. trachomatis, Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma urealyticum, and Ureaplasma parvum in first-voided urine specimens were detected by polymerase chain reaction assay. Detection rates were 1% for M. genitalium, 4% for M. hominis, 12% for U. urealyticum, and 23% for U. parvum. C. trachomatis was detected in 6% of samples. No M. hominis, U. urealyticum, or U. parvum was detected simultaneously in any sample positive for C. trachomatis. The detection rate of urinary M. genitalium was extremely low, which is similar to previous reports from Japan. The detection rates of urethral U. urealyticum and U. parvum were significantly related to sexual activity. We need to determine whether these pathogens have a role in the sexual transmission of disease or just in colonization.

Adolescent↗
PubMed1996

Correlations between Mycoplasma pneumoniae sensitivity to cyclosporin A and cyclophilin-mediated regulation of mycoplasma cytadherence.

Adhesins and adhesin-related accessory proteins of the bacterial pathogen, Mycoplasma pneumoniae, are proline-rich in composition and mediate successful parasitism of host target cells. A specific class of peptidyl-proyl cis-trans isomerases (PPIs), called cyclophilins (Cyps), activate proline-rich proteins, and this enzymatic activity is inhibited by the drug, cyclosporin A (CsA). This study builds upon the connection between the structural/functional properties of the proline-rich proteins of M. pneumoniae and the mode of action of CsA to demonstrate that CsA reduces cytadherence capabilities of mycoplasmas, affects colony morphology and can be mycoplasmacidal. As a consequence of CsA treatment early passage mycoplasmas lacked the major adhesin, P1, explaining their cytadherence-negative phenotype. Three mycoplasma proteins with molecular masses of 160, 84 and 80 kDa were identified by CsA-affinity chromatography. A PCR cloned partial cyp gene of M. pneumoniae, which exhibited sequence homologies with prokaryotic and eukaryotic cyclophilins, was present in multiple copies. These results implicate the role of PPIs as important regulators of cytadherence, virulence and growth cycle events in mycoplasmas.

Amino Acid Isomerases↗
PubMed1984

Elimination of mycoplasmas from cell cultures and establishment of mycoplasma-free cell lines.

Several antibiotics were examined for their potential to eliminate mycoplasmas from contaminated cell cultures. Acholeplasma laidlawii, Mycoplasma arginini, Mycoplasma hyorhinis and Mycoplasma orale were effectively eliminated from experimentally contaminated mouse fibroblasts and mink epithelial cells by the use of the antibiotics minocycline and tiamutin . An elimination procedure was established, which involved the consecutive treatment of the cultures over a period of 3 weeks, followed by cell cloning. This procedure was effective when applied to cell lines which had been contaminated with unidentified and partially non-cultivable strains of mycoplasmas.

Animals↗
PubMed1987

Production of mycoplasma-specific antisera in rabbits immunologically tolerized at birth to mycoplasma medium constituents.

Neonatal rabbits were injected intraperitoneally (i.p.) within 12 h of birth followed by similar injections every day for 10 consecutive days and then every second day for a further 8 weeks, with mycoplasma broth medium (tolerogen), to induce immune tolerance. The rabbits were then immunized with the porcine mycoplasmas, M. hyopneumoniae or M. hyorhinis at 9 weeks of age. Immune sera obtained from these rabbits and from normal control rabbits were tested for antibodies against both mycoplasma antigens and for antibodies to medium components by double immunodiffusion in agarose and by enzyme-linked immunosorbent assay (ELISA). Antisera obtained from the tolerized rabbits contained no antibodies to medium components as evidenced by lack of reactivity in both assays. In immunofluorescence tests the antisera obtained from tolerized rabbits permitted specific staining of colonies of the homologous mycoplasma grown on mycoplasma agarose medium. In contrast the antisera obtained from normal rabbits produced strong reactions in all of the tests and non-specific background fluorescence due to reactions with components of the culture medium.

Animals↗
PubMed2000

Effect of Mycoplasma bovis and Mycoplasma bovigenitalium in semen on fertilization and association with in vitro produced morula and blastocyst stage embryos.

Frozen-thawed bovine semen contaminated with Mycoplasma bovis (M. bovis) or Mycoplasma bovigenitalium (M. bovigenitalium) at either a high (10(6) CFU/mL) or low (10(4) CFU/mL) concentration was used for bovine oocyte insemination. The resulting embryos were washed 10 times as recommended by the International Embryo Transfer Society (IETS) prior to isolation of agent. A total of 1494 oocytes was inseminated with contaminated sperm cells and 855 oocytes with uninfected control semen. There was a significantly higher proportion of embryos that developed to the blastocyst stage in control than in the mycoplasma exposed groups (P<0.05). Isolation of motile spermatozoa by swim-up procedure prior to insemination did not render sperm cells free of Mycoplasma spp. Although M. bovis was isolated from all washed embryos after the high exposure level, it was found in only 60% of the samples after the low exposure level. In contrast, M. bovigenitalium was isolated from 70 and 12% of washed embryos exposed to the high and low levels of microorganism, respectively. Using scanning electron microscopy, both microorganisms were detected in association with the surface of zona pellucida-intact embryos and with sperm cells. These results indicate that mycoplasmas present in semen can be transmitted through the IVF system and infect embryos. Furthermore, the experiments showed that supplementation of culture media with standard antibiotics and washing embryos as recommended by IETS were not effective in rendering IVF embryos free from M. bovis and M. bovigenitalium.

Acrosome↗