The flagellated protozoon
Trichomonas vaginalis
, responsible for trichomoniasis, can establish a symbiotic relationship with the bacterium
Mycoplasma hominis
and can harbor double-stranded RNA
...Trichomonasvirus
(TVV). In this study, we investigated by real-time PCR the prevalence of the four TVVs and of
M. hominis
among 48
T. vaginalis
strains isolated in Italy, and we evaluated a possible association with metronidazole resistance. Fifty percent of the analyzed trichomonad strains tested positive for at least one TVV
T. vaginalis
, with TVV2 being the most prevalent, followed by TVV1 and TVV3. Two
T. vaginalis
strains were infected by TVV4, detected in Europe for the first time. Interestingly, we found more than one TVV species in 75% of positive trichomonad strains.
M. hominis
was present in 81.25% of
T. vaginalis
isolates tested, and no statistically significant association was observed with the infection by any TVV. Metronidazole sensitivity of
T. vaginalis
isolates was evaluated
in vitro
, and no correlation was observed between minimal lethal concentration and the presence of TVVs. This is the first report on TVV infection of
T. vaginalis
in Italy. Even if no association of TVV positive isolates with the presence of the symbiont
M. hominis
or with metronidazole resistance was observed, further studies are needed to shed light on the effective role of infecting microorganisms on the pathophysiology of
T. vaginalis.
Antibiotic resistance in Ureaplasma urealyticum/Ureaplasma parvum and Mycoplasma hominis is an issue of increasing importance. However, data regarding the susceptibility and, more importantly, the ...clonality of these organisms are limited. We analyzed 140 genital samples obtained in Bern, Switzerland, in 2014. Identification and antimicrobial susceptibility tests were performed by using the Mycoplasma IST 2 kit and sequencing of 16S rRNA genes. MICs for ciprofloxacin and azithromycin were obtained in broth microdilution assays. Clonality was analyzed with PCR-based subtyping and multilocus sequence typing (MLST), whereas quinolone resistance and macrolide resistance were studied by sequencing gyrA, gyrB, parC, and parE genes, as well as 23S rRNA genes and genes encoding L4/L22 ribosomal proteins. A total of 103 samples were confirmed as positive for U. urealyticum/U. parvum, whereas 21 were positive for both U. urealyticum/U. parvum and M. hominis. According to the IST 2 kit, the rates of nonsusceptibility were highest for ciprofloxacin (19.4%) and ofloxacin (9.7%), whereas low rates were observed for clarithromycin (4.9%), erythromycin (1.9%), and azithromycin (1%). However, inconsistent results between microdilution and IST 2 kit assays were recorded. Various sequence types (STs) observed previously in China (ST1, ST2, ST4, ST9, ST22, and ST47), as well as eight novel lineages, were detected. Only some quinolone-resistant isolates had amino acid substitutions in ParC (Ser83Leu in U. parvum of serovar 6) and ParE (Val417Thr in U. parvum of serovar 1 and the novel Thr417Val substitution in U. urealyticum). Isolates with mutations in 23S rRNA or substitutions in L4/L22 were not detected. This is the first study analyzing the susceptibility of U. urealyticum/U. parvum isolates in Switzerland and the clonality outside China. Resistance rates were low compared to those in other countries. We hypothesize that some hyperepidemic STs spread worldwide via sexual intercourse. Large combined microbiological and clinical studies should address this important issue.
In vitro activities of omadacycline, a new aminomethylcycline, were determined for Mycoplasma and Ureaplasma spp. and compared with those of azithromycin, clindamycin, moxifloxacin, tetracycline, and ...doxycycline. All omadacycline MICs were <2 μg/ml. MIC
s were 0.063 μg/ml for Mycoplasma hominis, 0.25 μg/ml for Mycoplasma pneumoniae, and 2 μg/ml for Ureaplasma spp. Omadacycline had the lowest MIC
among all drugs tested against M. hominis Omadacycline activity was not affected by macrolide, tetracycline, or fluoroquinolone resistance.
is a bacterium belonging to the class
. It causes acute and chronic infections of the urogenital tract. The main features of this bacterium are an absence of cell wall and a reduced genome size ...(517-622 protein-encoding genes). Previously, we have isolated morphologically unknown
colonies called micro-colonies (MCs) from the serum of patients with inflammatory urogenital tract infection.
MCs are functionally different from the typical colonies (TCs) in terms of metabolism and cell division.
To determine the physiological differences between MCs and TCs of
and elucidate the pathways of formation and growth of MCs by a comparative proteomic analysis of these two morphological forms.
LC-MS proteomic analysis of TCs and MCs using an Ultimate 3000 RSLC nanoHPLC system connected to a QExactive Plus mass spectrometer.
The study of the proteomic profiles of
colonies allowed us to reconstruct their energy metabolism pathways. In addition to the already known pentose phosphate and arginine deamination pathways,
can utilise ribose phosphate and deoxyribose phosphate formed by nucleoside catabolism as energy sources. Comparative proteomic HPLC-MS analysis revealed that the proteomic profiles of TCs and MCs were different. We assume that MC cells preferably utilised deoxyribonucleosides, particularly thymidine, as an energy source rather than arginine or ribonucleosides. Utilisation of deoxyribonucleosides is less efficient as compared with that of ribonucleosides and arginine in terms of energy production. Thymidine phosphorylase DeoA is one of the key enzymes of deoxyribonucleosides utilisation. We obtained a DeoA overexpressing mutant that exhibited a phenotype similar to that of MCs, which confirmed our hypothesis.
In addition to the two known pathways for energy production (arginine deamination and the pentose phosphate pathway)
can use deoxyribonucleosides and ribonucleosides. MC cells demonstrate a reorganisation of energy metabolism: unlike TC cells, they preferably utilise deoxyribonucleosides, particularly thymidine, as an energy source rather than arginine or ribonucleosides. Thus MC cells enter a state of energy starvation, which helps them to survive under stress, and in particular, to be resistant to antibiotics.
Abstract
Mycoplasma lipoproteins play a relevant role in pathogenicity and directly interact with the host immune system. Among human mycoplasmas, Mycoplasma hominis is described as a commensal ...bacterium that can be associated with a number of genital and extragenital conditions. Mechanisms of M. hominis pathogenicity are still largely obscure, and only a limited number of proteins have been associated with virulence. The current study focused on investigating the role of MHO_0730 as a virulence factor and demonstrated that MHO_0730 is a surface lipoprotein, potentially expressed in vivo during natural infection, acting both as a nuclease with its amino acidic portion and as a potent inducer of Neutrophil extracellular trapsosis with its N-terminal lipid moiety. Evidence for M. hominis neutrophil extracellular trap escape is also presented. Results highlight the relevance of MHO_0730 in promoting infection and modulation and evasion of innate immunity and provide additional knowledge on M. hominis virulence and survival in the host.
Mycoplasma lipoproteins play a relevant role in pathogenicity. In this study we investigate the role of Mycoplasma hominis MHO_0730 as a virulence factor. Results highlight the relevance of MHO_0730 in promoting infection and modulating and evading the host immune response.
In
, two genes (
and
) have been found to be associated with the invasion of the amniotic cavity, and a single gene (
) to be associated with intra-amniotic infections and a high risk of preterm ...birth. The syntopic presence of
spp. in the same patient has been shown to correlate with the absence of
in
. The aim of our study was to investigate the presence of
,
, and
genes in two groups of
isolates collected from symptomatic and asymptomatic male and non-pregnant female patients attending an Outpatients Centre. Group A consisted of 26 isolates from patients with only
confirmed; group B consisted of 24 isolates from patients with
spp. as the only co-infection. We extracted DNA from all
isolates and analysed the samples for the presence of
,
, and
in a qPCR assay. Additionally, we determined their cytotoxicity against HeLa cells. We confirmed the presence of the
gene in 85% of group A isolates and in 100% of group B isolates;
was detected in 46% of the samples in both groups, whereas
was found in 73% of group A and 79% of group B isolates, respectively. It was shown that co-colonisation with
spp. in the same patient had no effect on the presence of
in the respective
isolate. We did not observe any cytotoxic effect of the investigated isolates on human cells, regardless of the presence or absence of the investigated genes.
Mycoplasma hominis is an opportunistic human mycoplasma. Two other pathogenic human species, M. genitalium and Ureaplasma parvum, reside within the same natural niche as M. hominis: the urogenital ...tract. These three species have overlapping, but distinct, pathogenic roles. They have minimal genomes and, thus, reduced metabolic capabilities characterized by distinct energy-generating pathways. Analysis of the M. hominis PG21 genome sequence revealed that it is the second smallest genome among self-replicating free living organisms (665,445 bp, 537 coding sequences (CDSs)). Five clusters of genes were predicted to have undergone horizontal gene transfer (HGT) between M. hominis and the phylogenetically distant U. parvum species. We reconstructed M. hominis metabolic pathways from the predicted genes, with particular emphasis on energy-generating pathways. The Embden-Meyerhoff-Parnas pathway was incomplete, with a single enzyme absent. We identified the three proteins constituting the arginine dihydrolase pathway. This pathway was found essential to promote growth in vivo. The predicted presence of dimethylarginine dimethylaminohydrolase suggested that arginine catabolism is more complex than initially described. This enzyme may have been acquired by HGT from non-mollicute bacteria. Comparison of the three minimal mollicute genomes showed that 247 CDSs were common to all three genomes, whereas 220 CDSs were specific to M. hominis, 172 CDSs were specific to M. genitalium, and 280 CDSs were specific to U. parvum. Within these species-specific genes, two major sets of genes could be identified: one including genes involved in various energy-generating pathways, depending on the energy source used (glucose, urea, or arginine) and another involved in cytadherence and virulence. Therefore, a minimal mycoplasma cell, not including cytadherence and virulence-related genes, could be envisaged containing a core genome (247 genes), plus a set of genes required for providing energy. For M. hominis, this set would include 247+9 genes, resulting in a theoretical minimal genome of 256 genes.
Trichomonas vaginalis is the causative agent of trichomoniasis, one of the most common sexually transmitted diseases worldwide. In recent years we have described the symbiotic relationship between T ...vaginalis and Mycoplasma hominis. How this biological association might affect the pathogenicity of one or both the microorganisms is still unknown. Since local inflammation is thought to play a central role in T vaginalis infection, we investigated the in vitro response of human macrophages to naturally mycoplasma-free T vaginalis, as compared to a mycoplasma-infected trichomonad isolate.
THP-1 cells were stimulated with two isogenic T vaginalis isolates, one naturally mycoplasma-free and one stably associated with M hominis, and secreted cytokines measured by ELISA. Nuclear factor κB (NFκB) involvement in THP-1 response to T vaginalis and M hominis was evaluated by means of a reporter system based on detection of alkaline phosphatase activity.
We found that the presence of M hominis upregulates the expression of a panel of proinflammatory cytokines in a synergistic fashion. We also found that the upregulation of the proinflammatory response by THP-1 cells involves the transcription factor NFκB.
These findings suggest that the presence of M hominis in T vaginalis isolates might play a key role in inflammation during trichomoniasis, thus affecting the severity of the disease. The synergistic upregulation of the macrophage proinflammatory response might also affect some important clinical conditions associated with T vaginalis infection, such as the increased risk of acquiring cervical cancer or HIV, which are thought to be affected by the inflammatory milieu during trichomoniasis.
Mycoplasma hominis (M.hominis) infections are sexually transmitted and usually associated with urogenital and respiratory diseases. The aim of our study was to (i) detect M. hominis in the vaginal ...and urine samples of sexually active women using three different detection methods and (ii) to determine the antimicrobial susceptibility and recurrence after the treatment.
Both vaginal and urine samples were collected from 110 sexually active women at the Obstetrics and Gynecology Clinic, Başkent University Ankara Hospital, Turkey, between March 2015 and February 2016. The presence of M. hominis in the vaginal and urine samples was detected by in vitro culture, two biochemical diagnostics kits (Mycoplasma IES (Autobio, China) and Mycoplasma IST–2 (BioMérieux, France) and PCR. The antibiotic susceptibility of each sample was tested using the kits. The women positive for M. hominis were treated either singly or along with their sexual partners by tetracycline.
M. hominis was detected in 72 of 220 (32.7%) samples (both vaginal and urine). Of which 37 showed contrary results with two different kits and then were confirmed by PCR. In 13 samples the IES kit identified M. hominis missed by IST-2, and in 8 samples the MIST-2 kit identified M. hominis missed by IES, while both kits missed 6 samples that were agar culture positive for M. hominis.” The highest susceptibility rate was observed against pristinamycin (100%), followed by 91%, 83%, and 75% for doxycycline, tetracycline, and josamycin, respectively. Twenty-five patients treated with tetracycline were followed after one month. The recurrence of M. hominis was not observed in any of the 18 cases where both sexual partners were treated but recurred in 5 of the 7 singly treated women.
The rate of M. hominis detection was significantly higher in the vaginal samples compared to the urine samples. The probability of detecting M. hominis by IST–2 kit was 1.18 times less than IES kit (p < 0.001). When the relationship between the samples was examined, the difference between IES and IST–2 for detecting M. hominis was statistically significant (p < 0.01). Antibiotic susceptibility tests indicated that the tetracycline group of antibiotics was effective in eliminating M. hominis when given to both the sexual partners.
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