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PLoS Genetics 2013In the bacterial world, methylation is most commonly associated with restriction-modification systems that provide a defense mechanism against invading foreign genomes....
In the bacterial world, methylation is most commonly associated with restriction-modification systems that provide a defense mechanism against invading foreign genomes. In addition, it is known that methylation plays functionally important roles, including timing of DNA replication, chromosome partitioning, DNA repair, and regulation of gene expression. However, full DNA methylome analyses are scarce due to a lack of a simple methodology for rapid and sensitive detection of common epigenetic marks (ie N(6)-methyladenine (6 mA) and N(4)-methylcytosine (4 mC)), in these organisms. Here, we use Single-Molecule Real-Time (SMRT) sequencing to determine the methylomes of two related human pathogen species, Mycoplasma genitalium G-37 and Mycoplasma pneumoniae M129, with single-base resolution. Our analysis identified two new methylation motifs not previously described in bacteria: a widespread 6 mA methylation motif common to both bacteria (5'-CTAT-3'), as well as a more complex Type I m6A sequence motif in M. pneumoniae (5'-GAN(7)TAY-3'/3'-CTN(7)ATR-5'). We identify the methyltransferase responsible for the common motif and suggest the one involved in M. pneumoniae only. Analysis of the distribution of methylation sites across the genome of M. pneumoniae suggests a potential role for methylation in regulating the cell cycle, as well as in regulation of gene expression. To our knowledge, this is one of the first direct methylome profiling studies with single-base resolution from a bacterial organism.
Topics: DNA Methylation; Gene Expression Regulation, Archaeal; Genome, Bacterial; Humans; Methyltransferases; Mycoplasma genitalium; Mycoplasma pneumoniae; Nucleotide Motifs
PubMed: 23300489
DOI: 10.1371/journal.pgen.1003191 -
Zhongguo Dang Dai Er Ke Za Zhi =... Aug 2018To study the clinical features of macrolide-resistant Mycoplasma pneumoniae pneumonia and its treatment regimens in children.
OBJECTIVE
To study the clinical features of macrolide-resistant Mycoplasma pneumoniae pneumonia and its treatment regimens in children.
METHODS
The samples of throat swab or bronchoalveolar lavage fluid were collected from 136 children with Mycoplasma pneumoniae pneumonia. Quantitative real-time PCR was used to detect 2063/2064 A:G mutation in 23S rRNA, and according to such results, the children were divided into drug-resistance group with 81 children and sensitive group with 55 children. The two groups were compared in terms of age composition, respiratory symptoms, extrapulmonary complications, laboratory markers, imaging changes, treatment regimens, and length of hospital stay.
RESULTS
Compared with the sensitive group, the drug-resistance group had significantly longer duration of pyrexia and severe fever, a significantly higher percentage of children with reduced blood oxygen saturation, and significantly higher levels of alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) (P<0.05). The conventional azithromycin treatment had a good clinical effect in the sensitive group, while corticosteroid therapy was usually needed in the drug-resistance group.
CONCLUSIONS
Macrolide-resistant Mycoplasma pneumoniae infection cannot be identified based on a single clinical feature, but prolonged duration of pyrexia and severe fever, reduced blood oxygen saturation, and increased ALT and LDH can suggest the presence of this disease. Azithromycin combined with glucocorticoids may be a good treatment regimen for children with macrolide-resistant Mycoplasma pneumoniae pneumonia.
Topics: Adolescent; Anti-Bacterial Agents; Azithromycin; Child; Child, Preschool; Drug Resistance, Bacterial; Female; Fever; Humans; Infant; Lung; Macrolides; Male; Mutation; Mycoplasma pneumoniae; Pneumonia, Mycoplasma; Treatment Outcome
PubMed: 30111471
DOI: 10.7499/j.issn.1008-8830.2018.08.006 -
MBio Jan 2018is an atypical bacterium that causes respiratory illnesses in humans, including pharyngitis, tracheobronchitis, and community-acquired pneumonia (CAP). It has also been...
is an atypical bacterium that causes respiratory illnesses in humans, including pharyngitis, tracheobronchitis, and community-acquired pneumonia (CAP). It has also been directly linked to reactive airway disease, asthma, and extrapulmonary pathologies. During its colonization, expresses a unique ADP-ribosylating and vacuolating cytotoxin designated ommunity-cquired espiratory istress yndrome (CARDS) toxin. CARDS toxin persists and localizes in the airway in CAP patients, asthmatics, and trauma patients with ventilator-associated pneumonia. Although CARDS toxin binds to specific cellular receptors, is internalized, and induces hyperinflammation, histopathology, mucus hyperplasia, and other airway injury, the intracellular trafficking of CARDS toxin remains unclear. Here, we show that CARDS toxin translocates through early and late endosomes and the Golgi complex and concentrates at the perinuclear region to reach the endoplasmic reticulum (ER). Using ER-targeted SNAP-tag, we confirmed the association of CARDS toxin with the ER and determined that CARDS toxin follows the retrograde pathway. In addition, we identified a novel CARDS toxin amino acid fingerprint, KELED, that is required for toxin transport to the ER and subsequent toxin-mediated cytotoxicity., a leading cause of bacterial community-acquired pneumonia (CAP) among children and adults in the United States, synthesizes a 591-amino-acid ADP-ribosylating and vacuolating protein, designated ommunity-cquired espiratory istress yndrome (CARDS) toxin. CARDS toxin alone is sufficient to induce and mimic major inflammatory and histopathological phenotypes associated with infection in rodents and primates. In order to elicit its ADP-ribosylating and vacuolating activities, CARDS toxin must bind to host cell receptors, be internalized via clathrin-mediated pathways, and subsequently be transported to specific intracellular organelles. Here, we demonstrate how CARDS toxin utilizes its unique KELED sequence to exploit the retrograde pathway machinery to reach the endoplasmic reticulum (ER) and fulfill its cytopathic potential. The knowledge generated from these studies may provide important clues to understand the mode of action of CARDS toxin and develop interventions that reduce or eliminate -associated airway and extrapulmonary pathologies.
Topics: Animals; Bacterial Proteins; Bacterial Toxins; Cell Line; Endoplasmic Reticulum; Humans; Mycoplasma pneumoniae; Protein Transport
PubMed: 29362229
DOI: 10.1128/mBio.01663-17 -
Clinical Microbiology and Infection :... Aug 2009Mycoplasma pneumoniae is an important respiratory pathogen, accounting for up to 25% of community-acquired pneumonia, and is a common cause of hospitalized pneumonia in... (Comparative Study)
Comparative Study
Mycoplasma pneumoniae is an important respiratory pathogen, accounting for up to 25% of community-acquired pneumonia, and is a common cause of hospitalized pneumonia in otherwise healthy adults and children. Mycoplasma pneumoniae isolates can be classified into two main genomic groups (type 1 and type 2) based on sequence variation within the gene encoding the major adhesion molecule P1. Although numerous publications have described real-time PCR assays for the detection of M. pneumoniae, none has been able to discriminate the two genomic types. Here, a real-time PCR assay that can distinguish each type of M. pneumoniae utilizing high-resolution melt-curve analysis is reported. Using this method, 102 isolates obtained from patients from 1965 to the present, including those from recent outbreaks, were typed along with reference strains M129 (type 1) and FH (type 2). The results show that 55 isolates (54%) can be classified as type 1 and 47 isolates (46%) as type 2, and 100% correlation was demonstrated when compared with a standard PCR-restriction fragment length polymorphism typing procedure. Typing of isolates obtained from recent outbreaks in the USA has revealed the presence of both types. This assay provides a rapid, reliable and convenient method for typing M. pneumoniae isolates and may be useful for surveillance purposes and epidemiological investigations, and may provide insight into the biology of M. pneumoniae distribution within populations.
Topics: Bacterial Typing Techniques; Base Sequence; DNA, Bacterial; Genotype; Humans; Molecular Epidemiology; Molecular Sequence Data; Mycoplasma pneumoniae; Pneumonia, Mycoplasma; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length; Sensitivity and Specificity; Transition Temperature; United States
PubMed: 19392882
DOI: 10.1111/j.1469-0691.2009.02814.x -
The Journal of International Medical... Apr 2020A 30-year-old woman was admitted to a different hospital with a 2-day history of fever, cough, and expectoration. She had a history of left pulmonary tuberculosis 8... (Review)
Review
A 30-year-old woman was admitted to a different hospital with a 2-day history of fever, cough, and expectoration. She had a history of left pulmonary tuberculosis 8 years previously. Chest computed tomography showed an infiltrate in the inferior lobe of the left lung and spot-like calcifications in the anterior lobe of the upper left lobe and lower lobe of the left lung. After antibacterial treatment, the patient’s condition deteriorated and she developed significant pleural effusion on the left side. The pleural effusion assay showed a lymphocyte-predominant exudate with a significantly increased adenosine deaminase level. The patient was transferred to our hospital with a suspected diagnosis of tuberculous pleuritis. A serum test for -specific immunoglobulin M was positive. Because of the limitations of this test in determining the occurrence of recent infection, a thoracoscopic pleural biopsy was performed, and DNA was detected in the biopsy tissue using -specific polymerase chain reaction. Thus, the patient was diagnosed with -related parapneumonic effusion. Clinicians must be aware of the usefulness and limitations of a high adenosine deaminase level and know that lymphocyte predominance in pleural effusion does not always indicate tuberculous pleurisy, especially in areas of high tuberculosis prevalence.
Topics: Adult; Diagnosis, Differential; Female; Humans; Mycoplasma pneumoniae; Pleural Effusion; Pneumonia, Mycoplasma; Tuberculosis, Pleural
PubMed: 32340523
DOI: 10.1177/0300060520918701 -
Italian Journal of Pediatrics Dec 2014Mycoplasma pneumoniae is a common cause of community-acquired pneumonia (CAP) in children. The aim of this study was to assess the prevalence of Mycoplasma pneumoniae...
BACKGROUND
Mycoplasma pneumoniae is a common cause of community-acquired pneumonia (CAP) in children. The aim of this study was to assess the prevalence of Mycoplasma pneumoniae infection in children with CAP and find clinical, radiological and laboratory features helpful to diagnose Mycoplasma pneumoniae pneumonia. Furthermore, we evaluated the value of serology, real-time PCR (RT-PCR) and culture for the accurate diagnosis of Mycoplasma pneumoniae pneumonia.
METHODS
The study included 166 children aged between 1 and 15 years with radiologically confirmed pneumonia. Throat swab specimens were cultured and assessed by RT-PCR for the presence of Mycoplasma pneumoniae. Mycoplasma pneumoniae-specific IgM and IgG antibodies were determined using ELISA in paired sera.
RESULTS
Mycoplasma pneumoniae pneumonia was diagnosed in 14.5% CAP cases. Cough (p=0.029), headache (p=0.001) and wheezing (p=0.036) were more frequent in children with Mycoplasma pneumoniae pneumonia compared to children with pneumonia caused by other pathogens. Logistic regression analysis showed that headache (odds ratio [OR] =36.077, p=0.001) and wheezing (OR=5.681, p=0.003) were significantly associated with MP pneumonia. Neither radiological findings, nor common laboratory parameters distinguished Mycoplasma pneumoniae infection in children with CAP. Using IgG serology in paired sera as the gold standard, we found that sensitivity of IgM serology, RT-PCR and culture was equal (81.82%), while specificity values were 100%, 98.6% and 100% respectively. We observed that combination of IgM detection in acute-phase serum and RT-PCR was positive for 91.7% of cases with Mycoplasma pneumoniae infection.
CONCLUSIONS
There are no characteristic radiological findings, or routine laboratory tests that would distinguish CAP caused by Mycoplasma pneumoniae from other CAP. It was found that clinical features such as headache and wheezing are indicative for Mycoplasma pneumoniae infection. Furthermore, it was found that during the acute phase of disease, detection of IgM antibodies in combination with RT-PCR allows for precise and reliable diagnosis of Mycoplasma pneumoniae infections in children.
Topics: Adolescent; Antibodies, Bacterial; Child; Child, Preschool; Clinical Laboratory Techniques; Community-Acquired Infections; DNA, Bacterial; Diagnosis, Differential; Female; Humans; Infant; Male; Mycoplasma pneumoniae; Pneumonia, Mycoplasma; Prevalence; Reproducibility of Results; Retrospective Studies; Serbia
PubMed: 25518734
DOI: 10.1186/s13052-014-0104-4 -
Molecular Systems Biology Dec 2020Protein degradation is a crucial cellular process in all-living systems. Here, using Mycoplasma pneumoniae as a model organism, we defined the minimal protein...
Protein degradation is a crucial cellular process in all-living systems. Here, using Mycoplasma pneumoniae as a model organism, we defined the minimal protein degradation machinery required to maintain proteome homeostasis. Then, we conditionally depleted the two essential ATP-dependent proteases. Whereas depletion of Lon results in increased protein aggregation and decreased heat tolerance, FtsH depletion induces cell membrane damage, suggesting a role in quality control of membrane proteins. An integrative comparative study combining shotgun proteomics and RNA-seq revealed 62 and 34 candidate substrates, respectively. Cellular localization of substrates and epistasis studies supports separate functions for Lon and FtsH. Protein half-life measurements also suggest a role for Lon-modulated protein decay. Lon plays a key role in protein quality control, degrading misfolded proteins and those not assembled into functional complexes. We propose that regulating complex assembly and degradation of isolated proteins is a mechanism that coordinates important cellular processes like cell division. Finally, by considering the entire set of proteases and chaperones, we provide a fully integrated view of how a minimal cell regulates protein folding and degradation.
Topics: Amino Acid Sequence; Bacterial Proteins; Gene Expression Regulation, Bacterial; Genome, Bacterial; Models, Biological; Mutation; Mycoplasma pneumoniae; Peptide Hydrolases; Phenotype; Protein Folding; Proteolysis; Quality Control; Reproducibility of Results; Substrate Specificity; Transcription, Genetic
PubMed: 33320415
DOI: 10.15252/msb.20209530 -
BMJ Case Reports Mar 2014We present a case of a young man with severe mucositis following an upper respiratory tract infection limited to the ophthalmic and oral mucosa while sparing the rest of...
We present a case of a young man with severe mucositis following an upper respiratory tract infection limited to the ophthalmic and oral mucosa while sparing the rest of the skin, genitalia and perianal regions. Investigations revealed that the mucositis was a rare extrapulmonary manifestation of Mycoplasma pneumoniae infection. He had progressive vision-threatening symptoms despite antibiotics and best supportive care and thus was treated with intravenous corticosteroids, immunoglobulins, temporary ocular amniotic membrane grafts and tarsorrhaphy. The patient made an almost complete recovery over 6 weeks.
Topics: Humans; Male; Mucositis; Mycoplasma Infections; Mycoplasma pneumoniae; Young Adult
PubMed: 24626386
DOI: 10.1136/bcr-2014-203795 -
Future Microbiology Feb 2017To characterize inter- and intra-strain variability of variable-number tandem repeats (VNTRs) in Mycoplasma pneumoniae to determine the optimal multilocus VNTR analysis...
AIM
To characterize inter- and intra-strain variability of variable-number tandem repeats (VNTRs) in Mycoplasma pneumoniae to determine the optimal multilocus VNTR analysis scheme for improved strain typing.
METHODS
Whole genome assemblies and next-generation sequencing data from diverse M. pneumoniae isolates were used to characterize VNTRs and their variability, and to compare the strain discriminability of new VNTR and existing markers.
RESULTS
We identified 13 VNTRs including five reported previously. These VNTRs displayed different levels of inter- and intra-strain copy number variations. All new markers showed similar or higher discriminability compared with existing VNTR markers and the P1 typing system.
CONCLUSION
Our study provides novel insights into VNTR variations and potential new multilocus VNTR analysis schemes for improved genotyping of M. pneumoniae.
Topics: DNA Copy Number Variations; DNA, Bacterial; Genetic Loci; Genetic Markers; Genotyping Techniques; High-Throughput Nucleotide Sequencing; Minisatellite Repeats; Mycoplasma pneumoniae; Sequence Analysis, DNA
PubMed: 27728978
DOI: 10.2217/fmb-2016-0111 -
BMC Microbiology Aug 2013Mycoplasma pneumoniae (Mpn) is a human pathogen that causes acute and chronic respiratory diseases and has been linked to many extrapulmonary diseases. Due to the lack...
BACKGROUND
Mycoplasma pneumoniae (Mpn) is a human pathogen that causes acute and chronic respiratory diseases and has been linked to many extrapulmonary diseases. Due to the lack of cell wall, Mpn is resistant to antibiotics targeting cell wall synthesis such as penicillin. During the last 10 years macrolide-resistant Mpn strains have been frequently reported in Asian countries and have been spreading to Europe and the United States. Therefore, new antibiotics are needed. In this study, 30 FDA-approved anticancer or antiviral drugs were screened for inhibitory effects on Mpn growth and selected analogs were further characterized by inhibition of target enzymes and metabolism of radiolabeled substrates.
RESULTS
Sixteen drugs showed varying inhibitory effects and seven showed strong inhibition of Mpn growth. The anticancer drug 6-thioguanine had a MIC (minimum inhibitory concentration required to cause 90% of growth inhibition) value of 0.20 μg ml(-1), whereas trifluorothymidine, gemcitabine and dipyridamole had MIC values of approximately 2 μg ml(-1). In wild type Mpn culture the presence of 6-thioguanine and dipyridamole strongly inhibited the uptake and metabolism of hypoxanthine and guanine while gemcitabine inhibited the uptake and metabolism of all nucleobases and thymidine. Trifluorothymidine and 5-fluorodeoxyuridine, however, stimulated the uptake and incorporation of radiolabeled thymidine and this stimulation was due to induction of thymidine kinase activity. Furthermore, Mpn hypoxanthine guanine phosphoribosyl transferase (HPRT) was cloned, expressed, and characterized. The 6-thioguanine, but not other purine analogs, strongly inhibited HPRT, which may in part explain the observed growth inhibition. Trifluorothymidine and 5-fluorodeoxyuridine were shown to be good substrates and inhibitors for thymidine kinase from human and Mycoplasma sources.
CONCLUSION
We have shown that several anticancer and antiviral nucleoside and nucleobase analogs are potent inhibitors of Mpn growth and that the mechanism of inhibition are most likely due to inhibition of enzymes in the nucleotide biosynthesis pathway and nucleoside transporter. Our results suggest that enzymes in Mycoplasma nucleotide biosynthesis are potential targets for future design of antibiotics against Mycoplasma infection.
Topics: Anti-Bacterial Agents; Drug Evaluation, Preclinical; Humans; Microbial Sensitivity Tests; Mycoplasma pneumoniae; Nucleosides
PubMed: 23919755
DOI: 10.1186/1471-2180-13-184