Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “MYCOPLASMA”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4Linked to original sources
PubMed1996

Interplay between mycoplasma surface proteins, airway cells, and the protean manifestations of mycoplasma-mediated human infections.

Adherence of mycoplasmas to specific tissue surfaces is a crucial step in the establishment of infection. Several pathogenic mycoplasmas are flask-shaped and possess specialized tips that permit a highly oriented surface parasitism of host target cells. Mycoplasma pneumoniae, which causes primary atypical pneumonia in humans, requires a network of interactive adhesins and accessory proteins to cytadhere. The adhesins must cluster at the mycoplasma tip organelle in close association with cytadherence-related accessory proteins and a naplike structure, which together appear to comprise a primitive cytoskeleton-like system. Proline-rich regions associated with these proteins play critical roles in the maintenance of the structural and functional integrity of the tip. Mycoplasma genitalium, originally isolated from the human urogenital tract of patients with nongonococcal urethritis, also colonizes airway cells along with M. pneumoniae. The molecular basis for cytadherence of these mycoplasmas is discussed in terms of the identification, cloning, and sequencing of the implicated mycoplasma genes, their common DNA and amino acid homologies and structural and functional domains, and the organizational similarities in their cytadherence-related operons. In addition, the multiorgan protean manifestations of mycoplasma infection are discussed in terms of the role that mycoplasma adhesins may play in molecular mimicry, postinfectious autoimmunity, and immune-mediated damage.

Adhesins, Bacterial↗
PubMed1999

Nitric oxide: a clinically important amniotic fluid marker to distinguish between intra-amniotic mycoplasma and non-mycoplasma infections.

The objective of this study was to determine whether the measurements of amniotic fluid nitric oxide metabolite (NOx: nitrate + nitrite) concentrations could be a clinically useful marker to differentiate between intra-amniotic mycoplasma and nonmycoplasma infections. Amniocentesis was performed on 76 pregnant women with suspicion of intra-amniotic infection. Intra-amniotic infection was defined as the presence of a positive amniotic fluid culture with either mycoplasma or nonmycoplasma infections. Rapid amniotic fluid tests for Gram stain, glucose, leukocyte counts, interleukin-6, and NOx were performed. Amniotic fluid NOx was measured with aspergillus nitrate reductase and Griess reagent. Interleukin-6 was determined by enzyme immunoassays. Amniotic fluid NOx and interleukin-6 were normalized by amniotic fluid creatinine levels. Patients with intra-amniotic mycoplasma (n = 7) and nonmycoplasma infections (n = 8) had significantly higher amniotic fluid leukocyte counts and interleukin-6 concentrations and significantly lower amniotic fluid glucose levels than noninfected controls (n = 61). Amniotic fluid concentrations of NOx were significantly higher in those with intraamniotic nonmycoplasma infection as compared to those with intraamniotic mycoplasma infection and noninfected controls (NOx: 3.35+/-0.74 vs. 2.03+/-0.41 micromol/mg creatinine, p = 0.005, and 3.35+/-0.74 vs. 1.72+/-0.07 micromol/mg creatinine, p < 0.0001, respectively). However, patients with intra-amniotic mycoplasma infection did not differ significantly from noninfected controls. Our data indicate that clinical characteristics of intra-amniotic mycoplasma infection may differ from intra-amniotic nonmycoplasma infection. As delivery is not always indicated in intra-amniotic mycoplasma infection, elevated rapid amniotic fluid tests (leukocyte counts, interleukin-6, and glucose) may not be appropriate in the clinical management of intra-amniotic mycoplasma infection. In addition to these rapid amniotic fluid tests, incorporation of the measurement of amniotic fluid NOx may be of clinical importance in the differentiation and management of patients with suspected intra-amniotic mycoplasma and nonmycoplasma infection.

Adult↗
PubMed1979

The incidence of Mycoplasma dispar, Ureaplasma and conventional Mycoplasma in the pneumonic calf lung.

This report describes the incidence of Mycoplasma dispar, ureaplasma and conventional (large colony) mycoplasma isolated from the pneumonic lungs of groups of young calves and the identification to species level of mycoplasmas in mixed populations with the aid of the indirect fluorescent antibody test. Pneumonic lung tissue yielded one or more mycoplasma species from 88% of the 153 calves cultured. The mycoplasmas identified and percent of the calves with lungs positive for each species were: M. dispar (56%), ureaplasma (44%), Mycoplasma bovis (37%), Mycoplasma arginini (33%) and Mycoplasma bovirhinis (23%). Conventional mycoplasmas isolated from two calves (1%) could not be identified using the antisera available.

Animals↗
PubMed1997

Polymerase chain reaction and restriction endonuclease digestion for selected members of the "Mycoplasma mycoides cluster" and Mycoplasma putrefaciens.

A specific diagnostic method using the polymerase chain reaction, together with restriction endonuclease digestion patterns, was developed for members of the "Mycoplasma mycoides cluster" that normally occur in the United States (i.e., Mycoplasma mycoides subsp. mycoides Large Colony and Mycoplasma capricolum subsp. capricolum in addition to "cluster" mycoplasma, bovine serogroup 7, and Mycoplasma putrefaciens. The digestion of "cluster" polymerase chain reaction DNA (1,225 bp) amplification products with restriction enzymes AseI and SspI gave mycoplasma species-specific patterns for all strains of M. mycoides subsp. mycoides Large Colony, M. capricolum subsp. capricolum, and bovine group 7 tested. Moreover, we found a nonspecific amplification product for M. putrefaciens that occurred with the oligonucleotide primers used for the "M. mycoides cluster" reaction. However, the restriction endonuclease digestion patterns observed with the restriction enzymes AluI, AseI, and SspI for M. putrefaciens were different than the digestion patterns obtained for the other "cluster" mycoplasmas. This report confirms the usefulness of polymerase chain reaction DNA amplification allied with restriction enzyme digestion profile analysis for the rapid and specific identification of mycoplasmas belonging to the "M. mycoides cluster" and M. putrefaciens.

Animals↗
PubMed1990

Mycoplasma somnilux sp. nov., Mycoplasma luminosum sp. nov., and Mycoplasma lucivorax sp. nov., new sterol-requiring mollicutes from firefly beetles (Coleoptera: Lampyridae).

Strain PYAN-1T (T = type strain), which was isolated from a pupal gut of the firefly beetle Pyractonema angulata, and strains PIMN-1T and PIPN-2T, which were isolated from guts of adult Photinus marginalis and Photinus pyralis fireflies, respectively, were demonstrated to be sterol-requiring mollicutes. Cells of the three strains were shown by electron and dark-field microscopy to be small, pleomorphic, nonhelical, nonmotile bodies surrounded by single membranes. No evidence of a cell wall was observed, and the organisms were not susceptible to 500 U of penicillin per ml. The three strains grew rapidly in SP-4 broth medium. Strains PIMN-1T and PIPN-2T grew in medium supplemented with bovine serum fraction, but strain PYAN-1T did not. All three strains grew on solid media when the cultures were incubated aerobically, but only strains PYAN-1T and PIPN-2T formed colonies when anaerobic conditions were employed. The three strains catabolized glucose but hydrolyzed neither arginine nor urea. All of the strains grew at temperatures of 18 to 32 degrees C; strains PYAN-1T and PIMN-1T also grew at 10 degrees C. The optimal temperature for growth for strains PYAN-1T and PIPN-2T was 30 degrees C; strain PIMN-1T grew equally well at 30 or 32 degrees C. None of the three strains grew at 37 degrees C. The genome sizes of strains PYAN-1T, PIMN-1T, and PIPN-2T were about 527 (478 to 589), 570 (480 to 630), and 762 (635 to 871) megadaltons, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1998

Detection of Mycoplasma genus and Mycoplasma fermentans by PCR in patients with Chronic Fatigue Syndrome.

Mycoplasma fermentans and other Mycoplasma species are colonizers of human mucosal surfaces and may be associated with human immunodeficiency virus infection. While many infectious agents have been described in different percentages of patients with Chronic Fatigue Syndrome (CFS), little is known about the prevalence of mycoplasmas and especially M. fermentans in CFS patients. A polymerase chain reaction (PCR)-based assay was used to detect Mycoplasma genus and M. fermentans genomes in peripheral blood mononuclear cells (PBMC) of CFS patients. Blood was collected from 100 patients with CFS and 50 control subjects. The amplified products of 717 bp of Mycoplasma genus, and 206 bp of M. fermentans were detected in DNA purified from blood samples in 52% and 34% of CFS samples, respectively. In contrast, these genomes were found in only 14% and 8% of healthy control subjects respectively (P < 0.0001). All samples were confirmed by Southern blot with a specific probe based on internal sequences of the expected amplification product. Several samples, which were positive for Mycoplasma genus, were negative for M. fermentans indicating that other Mycoplasma species are involved. A quantitative PCR was developed to determine the number of M. fermentans genome copies present in 1 microg of DNA for controls and CFS patients. Mycoplasma copy numbers ranging from 130 to 880 and from 264 to 2400 were detected in controls and CFS positive subjects, respectively. An enzyme immunoassay was applied for the detection of antibodies against p29 surface lipoprotein of M. fermentans to determine the relationship between M. fermentans genome copy numbers and antibody levels. Individuals with high genome copy numbers exhibited higher IgG and IgM antibodies against M. fermentans specific peptides. Isolation of this organism by culture from clinical specimens is needed in order to demonstrate specificity of signal detected by PCR in this study.

Adult↗
PubMed1997

Characterization of DNA topoisomerase activity in two strains of Mycoplasma fermentans and in Mycoplasma pirum.

DNA topoisomerases (topos) are essential enzymes that participate in many cellular processes involving DNA. The presence of the DNA-gyrase genes in various mycoplasmas has been reported elsewhere. However, the characterization of DNA topo activity in mycoplasmas has not been previously undertaken. In this study, we characterized the topo activity in extracts of Mycoplasma fermentans K7 and incognitus and in Mycoplasma pirum, as well as in partially purified extract of M. fermentans K7. The topo activity in these microorganisms had the following properties. (i) The relaxation of supercoiled DNA was ATP dependent. (ii) ATP independent relaxation activity was not detected. (iii) Supercoiling of relaxed topoisomers was not observed. (iv) The relaxation activity was inhibited by DNA gyrase and topo IV antagonists (novobiocin and oxolinic acid) and by eukaryotic topo II (m-AMSA [4'-(9-acridylamino)methanesulfon-m-anisidide]) and topo I antagonists (camptothecin). Other eukaryotic topo II antagonists (teniposide and etoposide) did not affect the topo relaxation activity. (v) Two polypeptides of 66 and 180 kDa were found to be associated with the mycoplasma topo activity. These results suggest that the properties of the topo enzyme in these mycoplasma species resemble those of the bacterial topo IV and the eukaryotic and the bacteriophage T4 topo II. The findings that mycoplasma topo is inhibited by both eukaryotic topo II and topo I antagonists and that m-AMSA and camptothecin inhibited the growth of M. fermentans K7 in culture support our conclusion that these mycoplasma species have topo with unique properties.

DNA Topoisomerase IV↗
PubMed2005

Pulsed-field gel electrophoresis patterns of Mycoplasma isolates from various body sites in dairy cattle with Mycoplasma mastitis.

OBJECTIVE: To determine whether Mycoplasma strains typically associated with mastitis in dairy cattle can be isolated from body sites other than the mammary gland. DESIGN: Prospective clinical trial. ANIMALS: 7 Holstein cows in various stages of lactation with intramammary Mycoplasma infection. PROCEDURE: Milk samples, antemortem swab specimens from various body sites, and postmortem swab and tissue specimens were submitted for Mycoplasma culture. Pulsed-field gel electrophoresis (PFGE) was performed on chromosomal digests of all Mycoplasma isolates. Isolates with the same number and size of chromosomal digest bands were considered to be of the same type. RESULTS: For each cow, all isolates obtained from milk, mammary gland parenchyma, and supramammary lymph nodes had the same PFGE pattern. All cows had at least 1 isolate from nonmammary system tissues that had the same PFGE pattern as isolates from the mammary system. Overall, 44 of the 70 (63%) Mycoplasma isolates obtained from body sites other than mammary system sites had the same PFGE pattern as did mammary system isolates. CONCLUSIONS AND CLINICAL RELEVANCE: Results confirmed our hypothesis that Mycoplasma strains isolated from the milk of dairy cattle with Mycoplasma mastitis frequently have PFGE patterns identical to those for strains isolated from other body sites, suggesting that there is at least a potential for internal transmission of Mycoplasma organisms.

Animals↗
PubMed2000

Pasteurization of discard mycoplasma mastitic milk used to feed calves: thermal effects on various mycoplasma.

Discard milk from sick or antibiotic-treated cows is often used as an economical alternative to milk replacer at dairy farms. This practice poses a health risk to calves if the discard milk is from cows with mycoplasma mastitis. Mycoplasma bovis, Mycoplasma californicum, and Mycoplasma canadense are among the agents known to cause contagious mastitis in cattle and occasionally pneumonia, otitis media, or arthritis in calves. This report describes a recent outbreak of calf polyarthritis and respiratory disease on a midwest dairy farm. The farm fed discard mycoplasma mastitic milk to its calves. On-the-farm pasteurization of the discard milk to 65 degrees C for 1 h before feeding prevented additional illness in the calves. Discard milk samples were collected before and after heating and tested for mycoplasma by culture. Only samples collected before pasteurization yielded live cultures. Common mastitic mycoplasma agents were also tested for sensitivity to heat. It was determined that 65 degrees C killed M. bovis and M. californicum after 2 min of exposure, while M. canadense remained viable for up to 10 min. Exposure to 70 degrees C inactivated M. bovis and M. californicum after 1 min, but M. canadense samples were positive for up to 3 min. Thus, M. canadense appears to be more heat resistant than M. bovis and M. californicum. Heat treatment that results in the destruction of M. canadense should be used for the pasteurization of discard mycoplasma mastitic milk.

Animal Feed↗
PubMed2000

Frequent contamination of Chlamydia trachomatis and Chlamydia pneumoniae strains with mycoplasma. Biological relevance and selective eradication of mycoplasma from chlamydial cultures with mupirocin.

Several strains of Chlamydia trachomatis (CT) and C. pneumoniae (CP) from different sources were screened for mycoplasma contamination using a sensitive nested 16S rDNA polymerase chain reaction-specific for a broad range of mycoplasma species. Five of nine CT and 5/16 CP isolates were contaminated by mycoplasma. Mycoplasma fermentans, M. hyorhinis and M. hominis were found as contaminating agents. To our knowledge no data are available on whether coinfection of chlamydia with mycoplasma alters the biological behavior of chlamydia. Analysis of the biological effect of mycoplasma on chlamydial infection showed a profound mycoplasma-induced reduction of chlamydial growth. Mycoplasma were efficiently eliminated from chlamydial cultures in HEp-2 cells by treatment with mupirocin without affecting chlamydial replication or host cell growth. Two chlamydial strains, C. trachomatis serovar K and one clinical isolate of C. pneumoniae were purged by this method.

Anti-Bacterial Agents↗
PubMed1996

Application of a Mycoplasma group-specific PCR for monitoring decontamination of Mycoplasma-infected Chlamydia sp. strains.

Mycoplasma contamination of biological materials remains a major problem. Most contaminations are caused by the use of Mycoplasma-contaminated cell lines. We adapted a Mycoplasma group-specific PCR to detect Mycoplasma contamination in cell lines and demonstrate its use in monitoring decontamination procedures with Mycoplasma-contaminated suspensions of Chlamydia spp. Three different methods were investigated: the use of Mycoplasma-specific antiserum in cell culture, physical separation by the combined use of enzymatic treatment and differential centrifugation, and the use of detergents. With these methods only incubation with Triton X-100 resulted in decontamination of Mycoplasma-contaminated suspensions of several laboratory strains of Chlamydia pneumoniae, C. pecorum, and C. trachomatis. Only one C. pneumoniae strain, UZG-1, was sensitive to Triton X-100 treatment. Since 39 of 40 throat swabs from patients with symptoms of an upper respiratory tract infection had positive reactions in the Mycoplasma group-specific PCR, this procedure could also have clinical significance in attempts to propagate C. pneumoniae strains from clinical specimens.

Base Sequence↗
PubMed1965

Relationship of Mycoplasma pneumoniae to other human Mycoplasma species studied by gel diffusion.

Taylor-Robinson, David (National Institute of Allergy and Infectious Diseases, Bethesda, Md.), Otakar Sobeslavský, and Robert M. Chanock. Relationship of Mycoplasma pneumoniae to other human Mycoplasma species studied by gel diffusion. J. Bacteriol. 90:1432-1437. 1965.-Conditions are presented for the production of four lines of precipitate between Mycoplasma pneumoniae antigen and homologous hyperimmune rabbit serum in double diffusion in agar. The specificity of the reaction was shown by the fact that M. pneumoniae antigen did not react with antisera to the other human mycoplasma species, nor did M. pneumoniae antiserum produce lines with antigens prepared from the other human mycoplasmas. In addition, there was no reduction in the number or intensity of precipitation lines after absorption of M. pneumoniae antiserum with heterotypic mycoplasma antigens, or after absorption of heterotypic mycoplasma antisera with M. pneumoniae antigen. These findings indicate that, of the human mycoplasma species so far studied, M. pneumoniae is antigenically the most distinct.

Animals↗
PubMed2005

Phylogenetic analysis and description of Eperythrozoon coccoides, proposal to transfer to the genus Mycoplasma as Mycoplasma coccoides comb. nov. and Request for an Opinion.

Eperythrozoon coccoides, an epierythrocytic organism that causes a mild haemolytic anaemia in laboratory and wild mice, currently is thought to be a rickettsia. To determine the relationship of this agent to other haemotrophic bacterial parasites, the 16S rRNA gene of this organism has been sequenced and it is shown by phylogenetic analysis that this wall-less bacterium is not a rickettsia but actually is a mycoplasma. This mycoplasma shares properties with and is closely related to the other uncultivated mycoplasmas that comprise a recently identified group, the haemotrophic mycoplasmas (haemoplasmas). The haemoplasma group is composed of former Eperythrozoon and Haemobartonella species as well as newly identified haemotrophic mycoplasmas. Haemoplasmas parasitize the surface of erythrocytes of a wide variety of vertebrate animal hosts and are transmitted mainly by blood-feeding arthropod vectors. Because both primary infections and chronic latent infections caused by this bacterium have been observed in many laboratories and this bacterium has been the subject of much experimental work, considerable information exists about this haemotrophic mycoplasma that may be applicable to other haemoplasmas. It is proposed that Eperythrozoon coccoides be reclassified as Mycoplasma coccoides comb. nov. A Request for an Opinion is submitted to the Judicial Commission of the International Committee on Systematics of Prokaryotes regarding this reclassification.

Animals↗
PubMed1979

Haemadsorption inhibition test for the identification of Mycoplasma gallisepticum and Mycoplasma synoviae.

Colonies of the avian mycoplasma strains Mycoplasma gallisepticum S6 and Mycoplasma synoviae WVU 1853 and two Mycoplasma synoviae isolates from this laboratory were shown to be haemadsorption positive for chicken erythrocytes. Three Mycoplasma synoviae isolates from this laboratory proved to be haemadsorption and haemagglutination negative. The haemadsorption of the mycoplasma colonies mentioned above was inhibited with specific antisera of either high or low titre. No cross-inhibition was observed. It is suggested that this test could be used for a quick tentative identification of the two avian mycoplasmas on primary solid-medium cultures.

Animals↗
PubMed1966

Studies of PPLO infection. I. The production of cerebral polyarteritis by Mycoplasma gallisepticum in turkeys; the neurotoxic property of the Mycoplasma.

Turkey poults injected intravenously with suspensions of Mycoplasma gallisepticum develop a fatal neurologic disease associated with polyarteritis affecting almost exclusively the cerebral arteries. The incubation period depends on the dose of organisms. With high doses (10(10) to 10(11) mycoplasmas) the birds become ill and die within a few hours; with lower doses (10(6) to 10(8)) neurologic manifestations appear after 7 days. The rapid onset of neurologic signs after high doses indicates the presence of a toxin in the mycoplasma, but efforts to extract toxin from disrupted organisms or to demonstrate its presence in culture fluid free of mycoplasmas have been unsuccessful. The toxin appears to be associated only with living mycoplasmas. The toxic component of M. gallisepticum is inactivated by heating the organisms at 50 degrees C, disruption by repeated cycles of freezing and thawing, and exposure to specific antibody. Treatment of turkeys with gold thiomalate furnishes partial protection against the toxic effects of large doses of mycoplasmas, and protection against the development of cerebral arteritis. Treatment with tetracycline protects completely against both toxicity and arteritis, and, when delayed, restores diseased birds to a healthy state. Cortisone, methotrexate and 6-mercaptopurine have no effect on the course or outcome of the disease. Intracerebral injections of M. gallisepticum are less toxic and lethal than when the same dose was given by vein, indicating that the organism exerts its damaging action on blood vessels by way of the blood stream. The arterial lesions resemble those of serum sickness, except for their distribution, and are associated with glomerular inflammatory lesions. However, for various reasons discussed, it is considered more likely that they result from a direct toxic action of living mycoplasmas on the vessels concerned than from an immunologic mechanism.

Animals↗
PubMed1990

Enhancement of cytotoxicity of active macrophages by mycoplasma: role of mycoplasma-associated induction of tumor necrosis factor-alpha (TNF-alpha) in macrophages.

Tumor necrosis factor-alpha (TNF-alpha)-inducing activity of several mycoplasmas including Mycoplasma pneumoniae, a causative agent in human respiratory infectious diseases, was investigated. Purified peritoneal macrophages from BALB/c mice markedly enhanced their cytotoxic activity to Meth A cells, when cultured with either viable or non-viable mycoplasmas. The supernatants of the macrophage culture with mycoplasmas, M. pneumoniae and Acholeplasma laidlawii, showed the potent cytotoxic activity to TNF-alpha-sensitive L cells but not to TNF-alpha-insensitive L cells. Addition of anti-TNF-alpha antiserum inhibited completely the cytotoxic activity of these supernatants, indicating that a major part of the cytotoxic activity might be due to TNF-alpha. Various other mycoplasmas, either glucose- or arginine-utilizing species, as far as tested showed also the potent activity to produce TNF-alpha. These results strongly suggest the possibility that mycoplasmas possess the activity of TNF-alpha induction which might be responsible for a part of enhancement of cytotoxic activity of macrophages and resistance to infection with mycoplasmas in vivo.

Animals↗