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At least 19 recordsLinked to original sources

Taxonomy of the feline mycoplasmas Mycoplasma felifaucium, Mycoplasma feliminutum, Mycoplasma felis, Mycoplasma gateae, Mycoplasma leocaptivus, Mycoplasma leopharyngis, and Mycoplasma simbae by 16S rRNA gene sequence comparisons.

The nucleotide sequence of the 16S rRNA gene of eight mycoplasmas isolated from felids was determined and used for taxonomic comparisons. A signature nucleotide sequence motif and overall sequence similarity to other mollicutes positioned Mycoplasma felifaucium, Mycoplasma felis, Mycoplasma leocaptivus, Mycoplasma leopharyngis, and Mycoplasma simbae in the Mycoplasma fermentans phylogenetic group of mollicutes. Mycoplasma arginini and Mycoplasma gateae were positioned in the Mycoplasma hominis phylogenetic group of mollicutes, and Mycoplasma feliminutum was positioned in the phylogenetically distant Acholeplasma group of mollicutes, showing that host family preference does not necessarily derive from bacterial phylogenetic closeness.

Acholeplasma↗

[Mycoplasma synoviae control. I. Studies on the thermal sensitivity of pathogenic avian mycoplasmas (Mycoplasma synoviae, Mycoplasma gallisepicum and Mycoplasma meleagridis)].

A number of experiments were carried out to study the thermal sensitivity of Mycoplasma synoviae and Mycoplasma gallisepticum as well as that of young embryos in vitro and in ovo. A full mycoplasmacidal effect was attained after heating in bouillon cultures for six hours at 45 degrees C (including cultures of Mycoplasma meleagridis), for two and a half hours at 50 degrees C, for ninety minutes at 52 degrees C and for thirty minutes at 55 degrees C. Yoder's method of heating to control these mycoplasmas in hatching eggs was found to be inadequate. When inoculated eggs were heated for ten hours at 45 degrees C, mycoplasmas could no longer be isolated; however, this had a highly adverse effect on the proportion of eggs hatched (33 and 50 percent for hen's eggs and turkey eggs respectively). Mycoplasma synoviae was slightly more sensitive to heating than Mycoplasma gallisepticum, whereas Mycoplasma meleagridis showed more resistance than Mycoplasma gallisepticum. After heating, atypical colonies constantly appeared on the primary plates and conversion of glucose was delayed in the cultures. Isolation by SPF embryos was found to be a more sensitive method than isolation using artificial culture media only. When fresh incubated eggs were heated for ten hours at 45 degrees C, for two and a half hours at 46 degrees C or for thirty minutes at 47 degrees C, fifty percent of embryos died, whereas one hundred per cent died after heating for sixty minutes at 47 degrees C. Thermal treatment of hatching eggs to eliminate Mycoplasma synoviae, Mycoplasma gallisepticum and Mycoplasma meleagridis is unsuitable for use in poultry practice.

Animals↗

Sequences of the 16S rRNA genes and phylogeny of the goat mycoplasmas Mycoplasma adleri, Mycoplasma auris, Mycoplasma cottewii and Mycoplasma yeatsii.

The nucleotide sequences of the 16S rRNA genes from the type strains of four goat mycoplasmas, Mycoplasma adleri, Mycoplasma auris, Mycoplasma cottewii and Mycoplasma yeatsii, were determined by direct solid-phase DNA sequencing. Polymorphisms were found in two of the 16S rRNA gene sequences, showing the existence of two different rRNA operons. Three polymorphisms were found in M. adleri, and one was found in M. yeatsii. The sequence information was used for the construction of phylogenetic trees. M. adleri was included in the Mycoplasma lipophilum cluster within the hominis group. M. auris was comprised in the Mycoplasma hominis cluster of the hominis group. M. cottewii and M. yeatsii were found to be very closely related with only four nucleotide differences, and they grouped with Mycoplasma putrefaciens in the Mycoplasma mycoides cluster within the spiroplasma group. Sequencing of two field isolates of M. cottewii and M. yeatsii, geographically distant from the type strains, showed that the 16S rRNA gene from the field isolate of M. cottewii was identical to the one from the type strain. The field isolate of M. yeatsii had only two nucleotide differences to the type strain and these were present in only one of the two rRNA operons. Sequencing of the 16S rRNA genes from two unidentified mycoplasma isolates from Nepal indicated that they should both be regarded as M. auris strains.

Animals↗

Proposal to transfer some members of the genera Haemobartonella and Eperythrozoon to the genus Mycoplasma with descriptions of 'Candidatus Mycoplasma haemofelis', 'Candidatus Mycoplasma haemomuris', 'Candidatus Mycoplasma haemosuis' and 'Candidatus Mycoplasma wenyonii'.

Cell-wall-less uncultivated parasitic bacteria that attach to the surface of host erythrocytes currently are classified in the order Rickettsiales, family Anaplasmataceae, in the genera Haemobartonella and Eperythrozoon. Recently 16S rRNA gene sequences have been determined for four of these species: Haemobartonella felis and Haemobartonella muris and Eperythrozoon suis and Eperythrozoon wenyonii. Phylogenetic analysis of these sequence data shows that these haemotrophic bacteria are closely related to species in the genus Mycoplasma (class Mollicutes). These haemotrophic bacteria form a new phylogenetic cluster within the so-called pneumoniae group of Mycoplasma and share properties with one another as well as with other members of the pneumoniae group. These studies clearly indicate that the classification of these taxa should be changed to reflect their phylogenetic affiliation and the following is proposed: (i) that Haemobartonella felis and Haemobartonella muris should be transferred to the genus Mycoplasma as 'Candidatus Mycoplasma haemofelis' and 'Candidatus Mycoplasma haemomuris' and (ii) that Eperythrozoon suis and Eperythrozoon wenyonii should be transferred to the genus Mycoplasma as 'Candidatus Mycoplasma haemosuis' and 'Candidatus Mycoplasma wenyonii'. The former Haemobartonella and Eperythrozoon species described here represent a new group of parasitic mycoplasmas that possess a pathogenic capacity previously unrecognized among the mollicutes. These haemotrophic mycoplasmas have been given the trivial name haemoplasmas. These results call into question the affiliation of the remaining officially named species of Haemobartonella and Eperythrozoon which should be considered species of uncertain affiliation pending the resolution of their phylogenetic status.

Anaplasmataceae↗

Phylogeny of the seal mycoplasmas Mycoplasma phocae corrig., Mycoplasma phocicerebrale corrig. and Mycoplasma phocirhinis corrig. based on sequence analysis of 16S rDNA.

The nucleotide sequences of the 16S rRNA genes from the type strains of three seal mycoplasmas, Mycoplasma phocicerebrale, Mycoplasma phocae and Mycoplasma phocirhinis (formerly Mycoplasma phocacerebrale, Mycoplasma phocidae and Mycoplasma phocarhinis, respectively), were determined by direct DNA cycle sequencing. Polymorphisms were found in all three 16S rRNA gene sequences, showing the existence of two different rRNA operons. In M. phocae, a length difference was found between the operons, caused by an insertion or a deletion of an adenosine in one of the operons. The sequence information was used to construct phylogenetic trees. All three species were found to belong to the hominis group, but to different clusters. M. phocicerebrale and M. phocae were found to be members of the Mycoplasma hominis cluster, within which M. phocicerebrale grouped in the Mycoplasma alkalescens subcluster. M. phocirhinis was found to be a member of the Mycoplasma bovigenitalium subcluster of the Mycoplasma bovis cluster. The 16S rRNA gene sequences of all hitherto validly described species within the M. hominis and M. bovis clusters have now been determined.

Animals↗

Pneumonia due to mycoplasma in gnotobiotic mice. I. Pathogenicity of Mycoplasma pneumoniae, Mycoplasma salivarium, and Mycoplasma pulmonis for the lungs of conventional and gnotobiotic mice.

Lutsky, Irving I. (Marquette University School of Medicine, Milwaukee, Wis.), and Avrum B. Organick. Pneumonia due to mycoplasma in gnotobiotic mice. I. Pathogenicity of Mycoplasma pneumoniae, Mycoplasma salivarium, and Mycoplasma pulmonis for the lungs of conventional and gnotobiotic mice. J. Bacteriol. 92:1154-1163. 1966.-Two species of mycoplasma of human origin, Mycoplasma pneumoniae and M. salivarium, were tested for their ability to produce respiratory disease in the Ha/ICR mouse when inoculated by the intranasal route. The mouse pathogen M. pulmonis was studied as a positive control. Conventional and gnotobiotic Ha/ICR mice were employed, the latter to provide a system free from indigenous mycoplasma and bacteria. Pneumonia from which mycoplasma were isolated was produced in all groups of the conventional Ha/ICR mice, including those inoculated with sterile broth. Only M. pulmonis produced disease when inoculated intranasally into the gnotobiotic mice, and the gross and microscopic lesions resembled those described in conventional mice. The gnotobiotic mouse provided a tool to study the pathogenicity of different mycoplasma species, and indicated marked differences in host specificity that could not be clearly seen when conventional mice were used.

Animals↗

Morphology, ultrastructure, and mode of division of Mycoplasma fermentans, Mycoplasma hominis, Mycoplasma orale, and Mycoplasma salivarium.

The morphology of viable Mycoplasma fermentans, Mycoplasma hominis, Mycoplasma orale types 1 and 2, and Mycoplasma salivarium was studied in broth cultures by interference microscopy and in thin sections by electron microscopy. Only spherical cells were seen by interference microscopy. M. hominis had a capsule-like outer layer. Except for M. orale type 1, mycoplasmas in thin sections were 0.3-1 mum in diameter, with a bounding trilaminar membrane 7.5-10 nm thick. The mycoplasmas contained DNA fibrils and randomly distributed ribosomes. No polyribosomes were seen. Dividing mycoplasmas elongated slightly; the membrane invaginated, forming one bud. Sometimes M. hominis and M. salivarium produced one bud by elongation, and the bud was attached by a tube. This method of division is not considered as characteristic but rather as due to centrifugal force separating unfixed cells during preparation for electron microscopy. Cross-septa were never observed. In thin sections M. orale type 1 was elongated and without buds, an observation which suggested that preparation for electron microscopy distorted the mycoplasmas.

Cell Division↗

'Candidatus mycoplasma haemodidelphidis' sp. nov., 'Candidatus mycoplasma haemolamae' sp. nov. and Mycoplasma haemocanis comb. nov., haemotrophic parasites from a naturally infected opossum (Didelphis virginiana), alpaca (Lama pacos) and dog (Canis familiaris): phylogenetic and secondary structural relatedness of their 16S rRNA genes to other mycoplasmas.

The 16S rRNA sequence of newly characterized haemotrophic bacteria in an opossum (Didelphis virginiana) and alpaca (Lama pacos) was determined. In addition, the 16S rRNA sequence of a haemotrophic parasite in the dog (Canis familiaris) was determined. Sequence alignment and evolutionary analysis as well as secondary structural similarity and signature nucleotide sequence motifs of their 16S rRNA genes, positioned these organisms in the genus Mycoplasma. The highest scoring sequence similarities were 16S rRNA genes from haemotrophic mycoplasma species (Haemobartonella and Eperythrozoon spp.). However, the lack of several higher-order structural idiosyncrasies used to define the pneumoniae group, suggests that these organisms and related haemotrophic mycoplasmas represent a new group of mycoplasmas. It is recommended that the organisms be named 'Candidatus Mycoplasma haemodidelphidis', 'Candidatus Mycoplasma haemolamae' and Mycoplasma haemocanis comb. nov., to provide some indication of the target cell and host species of these parasites, and to reflect their phylogenetic affiliation.

Animals↗

Phylogenetic relationships of three porcine mycoplasmas, Mycoplasma hyopneumoniae, Mycoplasma flocculare, and Mycoplasma hyorhinis, and complete 16S rRNA sequence of M. flocculare.

The nucleotide sequence of the 16S rRNA gene of Mycoplasma flocculare was determined and was compared with the sequence of a related porcine mycoplasma, Mycoplasma hyopneumoniae. While the overall level of DNA-DNA homology was approximately 11%, sequence alignment of the two 16S rRNA genes yielded a homology value of more than 95%, emphasizing the highly conserved nature of the 16S rRNA gene. Multiple sequence alignments with other mollicutes indicated that M. flocculare, M. hyopneumoniae, and Mycoplasma hyorhinis form a subcluster within the fermentans phylogroup, and this subcluster is distinct from the Mycoplasma pneumoniae phylogroup. Thus, the three mycoplasmas isolated from porcine respiratory systems exhibit phylogenetic similarities.

Animals↗

Cross reactivity of Mycoplasma pulmonis and Mycoplasma arthritidis antigen strains to anti-Mycoplasma pulmonis antibody in the sera of Mycoplasma pulmonis infected rats.

Reactivity of Mycoplasma pulmonis (Mp) antigen strains to anti-Mp antibody in the sera of Mp infected rats was examined by enzyme linked immunosorbent assay (ELISA). Antibody titers to 7 kinds of Mp antigens were measured in the sera of 20 Mp isolated rats and 20 Mp free rats by ELISA and complement fixation test (CF test). ELISA showed that there was no difference in the antibody titer of the same serum among 7 Mp antigen strains employed, and the main cross reaction to anti-Mp antibody took place on the common recognition site (common antigen) in all the Mp antigens. The CF test suggested that the antibody titers largely differed due to the kind of Mp antigen strains, and the detection rate was between 0 and 60%, presumably due to the difference in the reactivity or binding ability of complements but not due to the difference in the cross reactivity of Mp antigen to anti-Mp antibody. When the cross reactivity of anti-Mp antibody to Mycoplasma arthritidis (Ma) antigen was examined in the sera of 33 Mp isolated rats, the CF test exhibited the negative results, but ELISA showed 4 positive cases to support the cross reactivity of anti-Mp antibody to Ma antigen.

Animals↗

In vitro amplification of the 16S rRNA genes from Mycoplasma bovirhinis, Mycoplasma alkalescens and Mycoplasma bovigenitalium by PCR.

Polymerase chain reaction (PCR) systems were developed for detection of 3 pathogenic bovine mycoplasmas, Mycoplasma alkalescens (Mak), M. bovigenitalium (Mbg) and M. bovirhinis (Mbr). The primers were selected from the sequences of the 16S rRNA from each of the mycoplasmas. Neither the Mbg-PCR system nor the Mbr-PCR system showed cross-amplification among 24 bovine, caprine-ovine and human mycoplasma species (including Acholeplasma and Ureaplasma species) tested. The Mak-PCR system showed cross-amplification with M. canadens ATCC29418T (T = type strain). The sensitivity of each PCR system to detect the proper mycoplasma was 10(3) colony forming units (CFU) when a pure culture was tested, and 2 x 10(3) CFU when the mycoplasma culture was spiked into a calf nasal swab sample. The target mycoplasmas in a clinical nasal swab sample that could be detected by the direct plate method could also be detected by these PCR systems.

Animals↗

Phylogenetic relationships of the porcine mycoplasmas Mycoplasma hyosynoviae and Mycoplasma hyopharyngis.

The phylogenetic positions of the porcine mycoplasmas Mycoplasma hyosynoviae and Mycoplasma hyopharyngis were determined by using PCR-amplified 16S rRNA gene sequences. M. hyosynoviae is a member of the Mycoplasma hominis group, while M. hyopharyngis belongs to the Mycoplasma fermentans group of mollicutes. Neither species is closely related to previously characterized porcine mycoplasmas belonging to the Mycoplasma hyorhinis group.

Animals↗

In vitro development of resistance to enrofloxacin, erythromycin, tylosin, tiamulin and oxytetracycline in Mycoplasma gallisepticum, Mycoplasma iowae and Mycoplasma synoviae.

The in vitro emergence of resistance to enrofloxacin, erythromycin, tylosin, tiamulin, and oxytetracycline in three avian Mycoplasma species, Mycoplasma gallisepticum, Mycoplasma synoviae and Mycoplasma iowae was studied. Mutants were selected stepwise and their MICs were determined after 10 passages in subinhibitory concentrations of antibiotic. High-level resistance to erythromycin and tylosin developed within 2-6 passages in the three Mycoplasma species. Resistance to enrofloxacin developed more gradually. No resistance to tiamulin or oxytetracycline could be evidenced in M. gallisepticum or M. synoviae after 10 passages whereas, resistant mutants were obtained with M. iowae. Cross-sensitivity tests performed on mutants demonstrated that mycoplasmas made resistant to tylosin were also resistant to erythromycin, whereas mutants made resistant to erythromycin were not always resistant to tylosin. Some M. iowae tiamulin-resistant mutants were also resistant to both macrolide antibiotics. Enrofloxacin and oxytetracycline did not induce any cross-resistance to the other antibiotics tested. These results show that Mycoplasma resistance to macrolides can be quickly selected in vitro, and thus, providing that similar results could be obtained under field conditions, that development of resistance to these antibiotics in vivo might also be a relatively frequent event.

Animals↗

In situ hybridisation for identification and differentiation of Mycoplasma hyopneumoniae, Mycoplasma hyosynoviae and Mycoplasma hyorhinis in formalin-fixed porcine tissue sections.

Oligonucleotide probes targeting 16S ribosomal RNA were designed for species-specific identification of the porcine mycoplasmas Mycoplasma hyopneumoniae, Mycoplasma hyorhinis and Mycoplasma hyosynoviae using a fluorescent in situ hybridisation assay. The specificity of the probes was evaluated using pure cultures as well as porcine tissue sections with artificial presence of mycoplasma, and the probes were found specific for the target organisms. The assay was applied on sections of 28 tissue samples from pigs infected with one or more of the three Mycoplasma species as determined by cultivation. M. hyopneumoniae and M. hyorhinis were identified in accordance with cultivation in lung sections from nine pigs affected by catarrhal to purulent bronchopneumonia. Likewise, in eight cases of fibrinous pericarditis, M. hyopneumoniae, M. hyorhinis and M. hyosynoviae were the infectious agents according to cultivation and were correctly identified by in situ hybridisation. Out of 11 joints cultivation positive for M. hyosynoviae, the probe was only able to identify M. hyosynoviae in eight cases probably due to a low number of microorganisms in the tissue sections. The in situ hybridisation assay is well suited for use in diagnostic and experimental work as well as a tool for pathogenesis studies.

Animals↗

Mycoplasma simbae sp. nov., Mycoplasma leopharyngis sp. nov., and Mycoplasma leocaptivus sp. nov., isolated from lions.

Mycoplasmas isolated from the throats of lions were shown to belong to three serotypes, all of which were serologically distinct from the previously recognized Mycoplasma and Acholeplasma spp. Eight mycoplasma colonies were cloned, including one from a leopard (strain LP), and were examined in detail for morphology, growth, and biochemical characteristics. The strains had the following properties: guanine-plus-cytosine contents of 37 mol% (strain LXT [T = type strain]), 28 mol% (strain LL2T), and 27 mol% (strain 3L2T) and a requirement for sterol. Strain 3L2T metabolized glucose, which was not metabolized by strains LXT and LL2T. Arginine and urea were not hydrolyzed. Strain LX (= NCTC 11724) is the type strain of a new species, Mycoplasma simbae; strain LL2 (= NCTC 11725) is the type strain of a second new species, Mycoplasma leopharyngis; and strain 3L2 (= NCTC 11726) is the type strain of a third new species, Mycoplasma leocaptivus.

Animals↗

Mycoplasma auris sp. nov., Mycoplasma cottewii sp. nov., and Mycoplasma yeatsii sp. nov., new sterol-requiring mollicutes from the external ear canals of goats.

Three mycoplasma strains, designated GIHT (T = type strain), UIAT, and VIST, were isolated from the external ear canals of goats and were shown to be serologically distinct from each other and from previously described Acholeplasma, Entomoplasma, Mesoplasma, and Mycoplasma species. Using light and transmission electron microscopy, we showed that the cells of these organisms were small, pleomorphic, coccoid, nonmotile, and nonhelical and that each cell was surrounded by a single cytoplasmic membrane. There was no evidence of a cell wall, and the organisms grew freely in media containing penicillin at concentrations of 1,000 U/ml or more and thallous acetate (final concentration, 1:4,000) and produced the "fried-egg" morphology typical of most mollicutes. Growth occurred both aerobically and anaerobically (as determined by the GasPak method). The ability to catabolize glucose and mannose and the ability to hydrolyze arginine varied among the three strains. All three strains required sterol for growth, and none of the strains hydrolyzed urea. The guanine-plus-cytosine contents of the DNAs of strains UIAT, VIST, and GIHT were determined to be 26.9, 27.0, and 26.6 mol%, respectively. Our data indicate that the three strains represent new Mycoplasma species, for which we propose the names Mycoplasma auris, Mycoplasma cottewii, and Mycoplasma yeatsii. The type strain of M. auris is UIA (= ATCC 51348 = NCTC 11731), the type strain of M. cottewii is VIS (= ATCC 51347 = NCTC 11732), and the type strain of M. yeatsii is GIH (= ATCC 51346 = NCTC 11730).

Animals↗

A pathological and immunohistochemical study of goat kids undergoing septicaemic disease caused by Mycoplasma capricolum subsp. capricolum, Mycoplasma mycoides subsp. capri and Mycoplasma mycoides subsp. mycoides (large colony type).

This paper studies the pathological and immunohistochemical findings in 12 kids experimentally infected with Mycoplasma capricolum subsp. capricolum (Mcc), M. mycoides subsp. capri (Mmc) and M. mycoides subsp. mycoides (large colony type), (MmmLC). For the demonstration of Mcc, Mmc and MmmLC antigens an immunoperoxidase technique based on the labelled streptavidin biotin method was used in the 12 kids inoculated with mycoplasmas and the three control kids inoculated with mycoplasma medium. All 12 kids, inoculated by different routes, developed subcutaneous swelling at the point of inoculation and terminated in fatal septicaemia from 1 to 5 days post inoculation. The histopathological findings consisted of cellulitis at the point of inoculation, acute diffuse interstitial pneumonia, arthritis and multifocal necrotic purulent splenitis in some kids. The Mcc, Mmc and MmmLC antigens were detected immunohistochemically in all kids with specific punctiform labelling inside the cytoplasm of the leucocytes or extracellularly at the inoculation point, respiratory airways, spleen, liver, joints, tonsils and lymph nodes. The results obtained in this study showed that the inoculation of these mycoplasmas by parenteral routes caused mycoplasmaemia. Moreover, the immunohistochemical results appear fully to confirm that the mycoplasmas were the cause of the death of the kids because of a septicaemic state.

Animals↗

Evidence that UGA is read as a tryptophan codon rather than as a stop codon by Mycoplasma pneumoniae, Mycoplasma genitalium, and Mycoplasma gallisepticum.

Molecular cloning and sequencing showed that Mycoplasma gallisepticum, like Mycoplasma capricolum, contains both tRNA(UCA) and tRNA(CCA) genes, while Mycoplasma pneumoniae and Mycoplasma genitalium each appear to have only a tRNA(UCA) gene. Therefore, these mycoplasma species contain a tRNA with the anticodon UCA that can translate both UGA and UGG codons.

Base Sequence↗