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International Journal of Infectious... Mar 2019Mycoplasma pneumoniae is a common cause of community-acquired pneumonia in humans. Treatment of infections can be complicated by the occurrence of macrolide resistant...
OBJECTIVES
Mycoplasma pneumoniae is a common cause of community-acquired pneumonia in humans. Treatment of infections can be complicated by the occurrence of macrolide resistant strains. The study was conducted to evaluate the presence of resistant strains in Cuba and to determine the corresponding genotypes.
METHODS
DNA of M. pneumoniae isolates and positive respiratory tract specimens collected in the years 2012 and 2017 were tested for resistance-associated mutations of 23S rRNA. In addition, strain types (P1 and MLVA) were determined.
RESULTS
Macrolide resistance mutations were confirmed in 5 out of 27 strains (18.5%). Whereas both P1 subtypes 1 and 2 as well variants V2a and V2c were identified, only two MLVA types (4/5/7/2 and 3/5/6/2) could be found.
CONCLUSIONS
During both sampling years, circulation of macrolide resistant strains was demonstrated. No association of resistance with a particular P1/MLVA type was found. Future longitudinal sampling to monitor prevalence of macrolide resistance of M. pneumoniae is recommended to verify the resistance pattern of this important pathogen of human respiratory tract infections.
Topics: Anti-Bacterial Agents; Community-Acquired Infections; Cuba; DNA, Bacterial; Drug Resistance, Bacterial; Genotyping Techniques; Humans; Macrolides; Mycoplasma pneumoniae; Pneumonia, Mycoplasma; RNA, Ribosomal, 23S; Respiratory Tract Infections; Specimen Handling
PubMed: 30634044
DOI: 10.1016/j.ijid.2018.12.018 -
Journal of Global Antimicrobial... Mar 2021The aim of this study was to investigate the biological characteristics and effect of antibiotic treatment for different Mycoplasma pneumoniae isolates co-infecting the...
OBJECTIVES
The aim of this study was to investigate the biological characteristics and effect of antibiotic treatment for different Mycoplasma pneumoniae isolates co-infecting the same patient.
METHODS
Two throat swab specimens from a single patient, on the day of admission (Sp01) and discharge (Sp13), were liquid cultured and subcultured on agar medium to obtain M. pneumoniae monoclones. The 23S rRNA gene of 50 monoclones from specimens Sp01 and Sp13 were analysed. Real-time PCR assay was used for detection of mutations and genotyping. Two typical monoclones were isolated for antimicrobial susceptibility testing.
RESULTS
Genotype 1 monoclones accounted for 70.8% (34/48) in Sp01 and 95.7% (44/46) in Sp13. All genotype 1 monoclones were of the 4-5-7-2 multilocus variable-number tandem-repeat analysis (MLVA) type, while all genotype 2 monoclones were 3-5-6-2 MLVA type. The genotype 1 monoclone, which harboured the A2063G mutation in 23S rRNA gene, was resistant to erythromycin and azithromycin in vitro, whilst genotype 2, which did not carry the mutation, was susceptible to macrolides. The proportion of macrolide-resistant M. pneumoniae monoclones in the specimen cultures collected rose from 70.8% to 95.7% at the time of discharge.
CONCLUSION
This is the first report on the isolation of macrolide-resistant and -susceptible strains of M. pneumoniae from the same patient. After treatment, the proportion of macrolide-resistant M. pneumoniae increased, but the patient still carried viable macrolide-susceptible strains, meaning that the macrolide-susceptible strains did not disappear completely.
Topics: Anti-Bacterial Agents; Drug Resistance, Bacterial; Humans; Macrolides; Microbial Sensitivity Tests; Mycoplasma pneumoniae; Pneumonia, Mycoplasma
PubMed: 33460841
DOI: 10.1016/j.jgar.2020.12.019 -
Antimicrobial Resistance and Infection... 2019The presence of macrolide-resistant has been frequently reported in recent years, especially in China. In this study, we investigated the antimicrobial susceptibility...
BACKGROUND
The presence of macrolide-resistant has been frequently reported in recent years, especially in China. In this study, we investigated the antimicrobial susceptibility and genotype against isolates from 2014 to 2016, Beijing.
METHODS
We investigated the activities of four antibiotics against 81 isolates in vitro All isolates were amplification of domains II and V of the 23S rRNA gene and the L4 and L22 ribosomal protein fragments. All isolates were genotyped with duplex real-time PCR, MLVA and VNTR detection in p1 gene.
RESULTS
The macrolide resistance rate was 65.4% (53/81). Each of the macrolide-resistant isolates was resistant to erythromycin (Minimum Inhibitory Concentration, MIC, ≥256 μg/ml) and azithromycin (MIC, 2-64 μg/ml), but susceptible to tetracycline and levofloxacin in vitro. Fifty two macrolide-resistant isolates harbored the A2063G mutation, and only 1 macrolide-resistant isolates harbored the A2064G mutation in domain V of the 23S ribosomal RNA gene. The C162A, A430G, and T279C mutations in the L4 and L22 ribosomal protein genes were not responsible for macrolide resistance, but they were related to the particular genotype of . 95.7% of type 1 isolates (45/47) were macrolide-resistance, and 23.5% of the type 2 isolates (8/34) were macrolide-resistance. Type 2 macrolide-resistance rate was 50.6% higher than that of the previous reports in China. The eight macrolide-resistant type 2 isolates were belong to 3/5/6/2 and 3/5/7/2 MLVA genotypes.
CONCLUSION
To our knowledge, this phenomenon likely resulted from a combination of genotype shifting from type1 to type 2 and antibiotic selection pressure in in China in recent years. The increase of resistance in type 2 is not due to the spread of same clone. However, the relationship between genotype shifts and macrolide resistance in needs to be further verified with more extensive surveillance data.
Topics: Anti-Bacterial Agents; Beijing; China; Drug Resistance, Bacterial; Erythromycin; Female; Genotype; Humans; Macrolides; Male; Microbial Sensitivity Tests; Mycoplasma pneumoniae; Pneumonia, Mycoplasma
PubMed: 30697421
DOI: 10.1186/s13756-019-0469-7 -
NPJ Systems Biology and Applications Oct 2020Mycoplasma pneumoniae is a slow-growing, human pathogen that causes atypical pneumonia. Because it lacks a cell wall, many antibiotics are ineffective. Due to its...
Mycoplasma pneumoniae is a slow-growing, human pathogen that causes atypical pneumonia. Because it lacks a cell wall, many antibiotics are ineffective. Due to its reduced genome and dearth of many biosynthetic pathways, this fastidious bacterium depends on rich, undefined medium for growth, which makes large-scale cultivation challenging and expensive. To understand factors limiting growth, we developed a genome-scale, constraint-based model of M. pneumoniae called iEG158_mpn to describe the metabolic potential of this bacterium. We have put special emphasis on cell membrane formation to identify key lipid components to maximize bacterial growth. We have used this knowledge to predict essential components validated with in vitro serum-free media able to sustain growth. Our findings also show that glycolysis and lipid metabolism are much less efficient under hypoxia; these findings suggest that factors other than metabolism and membrane formation alone affect the growth of M. pneumoniae. Altogether, our modelling approach allowed us to optimize medium composition, enabled growth in defined media and streamlined operational requirements, thereby providing the basis for stable, reproducible and less expensive production.
Topics: Culture Media, Serum-Free; Energy Metabolism; Glycolysis; Models, Biological; Mycoplasma pneumoniae
PubMed: 33097709
DOI: 10.1038/s41540-020-00153-7 -
Japanese Journal of Infectious Diseases Jan 2020The aim of this study was to explore whether there was any specific genotype responsible for the high prevalence of Mycoplasma pneumoniae infection in children. A total...
The aim of this study was to explore whether there was any specific genotype responsible for the high prevalence of Mycoplasma pneumoniae infection in children. A total of 247 M. pneumoniae-DNA positive clinical specimens including 200 from children and 47 from adults, collected in Beijing, China, during the same period, were analyzed. We performed P1-restriction fragment length polymorphism analysis (RFLP), multi-locus variable number tandem repeat analysis (MLVA) and detected the macrolide resistance-associated mutations in 23S rRNA of the clinical specimens. In the present study, we observed P1 genotype 1 and MLVA type M4-5-7-2 accounted for the majority of the cases across all ages in Beijing. Macrolide resistance-associated mutants of M. pneumoniae were also at a high level with 90.5% (181/200) in children and 76.6% (36/47) in adults. However, more diverse genotypes and a higher prevalence of macrolide resistance-associated mutations were found in the pediatric specimens. Further investigations are warranted to help to explain the difference of morbidity and molecular characteristics across the demographic spectrum.
Topics: Adult; Anti-Bacterial Agents; Bacterial Typing Techniques; Child; China; DNA, Bacterial; Drug Resistance, Bacterial; Genetic Variation; Genotype; Humans; Macrolides; Microbial Sensitivity Tests; Minisatellite Repeats; Mycoplasma pneumoniae; Pneumonia, Mycoplasma; Polymorphism, Restriction Fragment Length; Prevalence; RNA, Ribosomal, 23S
PubMed: 31474699
DOI: 10.7883/yoken.JJID.2019.037 -
Annals of Allergy, Asthma & Immunology... Aug 2017Acute infections with Mycoplasma pneumoniae (Mp) have been associated with worsening asthma in children. Mp can be present in the respiratory tract for extended periods;...
BACKGROUND
Acute infections with Mycoplasma pneumoniae (Mp) have been associated with worsening asthma in children. Mp can be present in the respiratory tract for extended periods; it is unknown whether the long-term persistence of Mp in the respiratory tract affects long-term asthma control.
OBJECTIVE
To determine the effect of Mp on asthma control.
METHODS
We enrolled 31 pediatric subjects 3 to 10 years of age with persistent asthma who completed up to 8 visits over a 24-month period. We detected Mp by antigen capture and polymerase chain reaction. Primary outcome measurements included symptom scores, quality of life, medication scores, oral corticosteroid use, health care usage, school absences, and exhaled breath condensate pH.
RESULTS
Low levels of Mp community-acquired respiratory distress syndrome toxin were detected in 20 subjects (64.5%) at enrollment. Subjects with Mp positivity at a given visit had a .579 probability of remaining Mp positive at the subsequent visit, whereas those with Mp negativity had a .348 probability of becoming Mp positive at the following visit. The incidence of Mp overall was higher in the spring and summer months. Overall, we found no significant relation between the detection of Mp and worse outcome measurements at the same visit or at subsequent visits.
CONCLUSION
The long-term persistence of Mp in the respiratory tract is common in children with asthma. However, the detection of Mp was not associated significantly with worse asthma symptoms, quality of life, health care usage, school absences, or exhaled breath condensate pH in this pediatric asthma cohort.
Topics: Asthma; Child; Child, Preschool; Female; Health Status; Humans; Male; Mycoplasma pneumoniae; Pneumonia, Mycoplasma; Prospective Studies; Quality of Life; Respiratory System; Seasons
PubMed: 28634021
DOI: 10.1016/j.anai.2017.05.022 -
Biomedical and Environmental Sciences :... Dec 2020The aim of this study is to investigate the macrolide resistance rate and molecular type with multiple-locus variable-number tandem-repeat analysis (MLVA) of of Beijing...
OBJECTIVE
The aim of this study is to investigate the macrolide resistance rate and molecular type with multiple-locus variable-number tandem-repeat analysis (MLVA) of of Beijing in 2016 in pediatric patients.
METHODS
Real-time quantitative polymerase chain reaction (PCR) was used to identify , and MLVA was performed. The domain V of the 23S rRNA was sequenced to detect macrolide-resistant point mutations. We also investigated the activities of antibiotics against isolates .
RESULTS
The PCR detection rate of in children in Beijing was 40%, and the macrolide resistance rate was 66%. The A2063G mutation in the 23S rRNA V region is the dominant mutation (137/146, 93.84%), whereas the A2064G mutation is rare (9/146, 6.16%). Seventy-three samples were typed successfully by MLVA typing, including 86.3% (63/73) were MLVA type 4-5-7-2, and 13.7% (10/73) were MLVA type 3-5-6-2. No other types were found. No strains were resistant to levofloxacin or tetracycline.
CONCLUSION
In 2016, a specific decrease in the macrolide resistance rate occurred in Beijing. The detection rate and macrolide resistance rate of outpatients are lower than those of inpatients. The A2063G mutants have high levels of resistance to erythromycin and azithromycin. The primary MLVA type is 4-5-7-2, followed by 3-5-6-2. No other MLVA types were detected. No strains resistant to tetracycline or levofloxacin were found .
Topics: Anti-Bacterial Agents; Beijing; Child; Drug Resistance, Bacterial; Genotype; Humans; Inpatients; Macrolides; Mutation; Mycoplasma pneumoniae; Outpatients; Polymerase Chain Reaction; RNA, Ribosomal, 23S; Respiratory Tract Infections
PubMed: 33472731
DOI: 10.3967/bes2020.125 -
Bioscience Reports Jan 2019is one of the most common pathogenic causes of community-acquired pneumonia. Hydrogen sulfide, alanine, and pyruvate producing enzyme (HapE) is a recently discovered...
is one of the most common pathogenic causes of community-acquired pneumonia. Hydrogen sulfide, alanine, and pyruvate producing enzyme (HapE) is a recently discovered virulence factor that can produce HS to promote erythrocyte lysis. However, other cytotoxic effects of HapE have not been explored. The present study examined the effects of this enzyme on normal human bronchial epithelial (NHBE) cells, in an attempt to identify additional mechanisms of pathogenesis. Recombinant HapE was purified for use in downstream assays. MTT and colony formation assays were conducted to determine the effects of HapE on cell viability and growth, while flow cytometry was used to examine changes in cell proliferation and cell cycle function. ELISA was performed to examine changes in the cytokine profile of HapE-treated cells. HapE treatment arrested NHBE cells in S phase and inhibited cell proliferation in a concentration-dependent manner. The anti-inflammatory factors interleukin (IL)-4 and IL-6 were significantly enhanced following HapE treatment. Increased secretion of pro-inflammatory factors was not observed. The effects of HapE on the respiratory epithelium may have an impact on the efficiency of host immune surveillance and pathogen elimination, and contribute to the pathogenesis of .
Topics: Bacterial Proteins; Bronchi; Cell Proliferation; Cytokines; Epithelial Cells; Humans; Mycoplasma pneumoniae; Pneumonia, Mycoplasma; Recombinant Proteins; Virulence Factors
PubMed: 30573530
DOI: 10.1042/BSR20182201 -
International Journal of Infectious... Jun 2019Analysis of the molecular characteristics of isolates is very important for clinical and epidemiological study of community-acquired pneumonia (CAP) caused by Mycoplasma...
BACKGROUND
Analysis of the molecular characteristics of isolates is very important for clinical and epidemiological study of community-acquired pneumonia (CAP) caused by Mycoplasma pneumoniae.
METHODS
Between 2010 and 2012, an epidemic period, M. pneumoniae was isolated from oropharyngeal swabs of consecutive CAP patients. Minimum inhibitory concentrations of macrolides, 23S rRNA gene sequencing, P1 gene and multilocus variable-number tandem-repeat analysis (MLVA) genotyping was conducted.
RESULTS
88.3% (181/205) of the isolates were macrolide-resistant M. pneumoniae (MRMP) and all harbored an A2063 G mutation. The strains were clustered into 7 MLVA types, and P1 type 1 and type 2 lineages were co-circulated (86.3% and 13.7%). Compared with adults, no specific MLVA type contributed to higher M. pneumoniae infection in children (p = 0.14). Similar macrolide profile and genotypes of M. pneumoniae was found between outpatients and inpatients. Significant differences in proportion of P1 types and two main MLVA types 4/5/7/2 and 3/5/6/2 were observed between MRMP and macrolide-sensitive M. pneumoniae (MSMP) (p < 0.001).
CONCLUSIONS
This study demonstrates a comprehensive profile of M. pneumoniae molecular characterization among CAP patients of all age, and provides more evidences on a correlation between MLVA type 4/5/7/2 and macrolide resistance in the setting of high incidence of MRMP.
Topics: Adult; Aged; Child; Child, Preschool; China; Community-Acquired Infections; Drug Resistance, Bacterial; Epidemics; Female; Humans; Infant; Macrolides; Male; Middle Aged; Mycoplasma pneumoniae; Pneumonia, Mycoplasma; Young Adult
PubMed: 30926541
DOI: 10.1016/j.ijid.2019.03.028 -
BMC Microbiology Apr 2014Adhesion of Mycoplasma pneumoniae (M. pneumoniae) to host epithelial cells requires several adhesin proteins like P1, P30 and P116. Among these proteins, P1 protein has...
BACKGROUND
Adhesion of Mycoplasma pneumoniae (M. pneumoniae) to host epithelial cells requires several adhesin proteins like P1, P30 and P116. Among these proteins, P1 protein has been inedited as one of the major adhesin and immunogenic protein present on the attachment organelle of M. pneumoniae. In the present study, we scanned the entire sequence of M. pneumoniae P1 protein to identify the immunodominant and cytadherence region(s). M. pneumoniae P1 gene was synthesized in four segments replacing all the UGA codons to UGG codons. Each of the four purified P1 protein fragment was analyzed for its immunogenicity with anti-M. pneumoniae M129 antibodies (Pab M129) and sera of M. pneumoniae infected patients by western blotting and ELISA. Antibodies were produced against all the P1 protein fragments and these antibodies were used for M. pneumoniae adhesion, M. pneumoniae adhesion inhibition and M. pneumoniae surface exposure assays using HEp-2 cells lines.
RESULTS
Our results show that the immunodominant regions are distributed throughout the entire length of P1 protein, while only the N- and C- terminal region(s) of P1 protein are surface exposed and block cytadhesion to HEp-2 cells, while antibodies to two middle fragments failed to block cytadhesion.
CONCLUSIONS
These results have important implications in designing strategies to block the attachment of M. pneumoniae to epithelial cells, thus preventing the development of atypical pneumonia.
Topics: Adhesins, Bacterial; Animals; Antibodies, Bacterial; Bacterial Adhesion; Blotting, Western; Enzyme-Linked Immunosorbent Assay; Hep G2 Cells; Humans; Mycoplasma pneumoniae; Protein Structure, Tertiary; Rabbits
PubMed: 24774062
DOI: 10.1186/1471-2180-14-108