23S rRNA Mutation A2074C Conferring High-Level Macrolide Resistance and Fitness Cost inCampylobacter jejuni

ABSTRACT A macrolide-resistant clinical isolate of Streptococcus pneumoniae with 23S rRNA mutations showed a heterogeneous phenotype and genotype. The mutant 23S rRNA genes from this isolate transformed susceptible strain R6 to resistance. Culture of resistant strain R6 in the absence of antibiotic pressure showed gene conversion to occur between the four 23S rRNA alleles, resulting in reversion to susceptibility with the resistant phenotype showing a fitness cost. These data explain the disappearance on subculture of heterogeneous macrolide resistance in the pneumococcus.

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Ribosomal Mutations Conferring Macrolide Resistance in Legionella pneumophila

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02188-16 ◽

2017 ◽

Vol 61 (3) ◽

Cited By ~ 13

Author(s):

Ghislaine Descours ◽

Christophe Ginevra ◽

Nathalie Jacotin ◽

Françoise Forey ◽

Joëlle Chastang ◽

...

Keyword(s):

Legionella Pneumophila ◽

Ribosomal Proteins ◽

Fold Increase ◽

Resistance Mechanisms ◽

Macrolide Resistance ◽

23S Rrna ◽

Content Type ◽

First Line Therapy ◽

High Level ◽

Domain V

ABSTRACT Monitoring the emergence of antibiotic resistance is a recent issue in the treatment of Legionnaires' disease. Macrolides are recommended as first-line therapy, but resistance mechanisms have not been studied in Legionella species. Our aim was to determine the molecular basis of macrolide resistance in L. pneumophila. Twelve independent lineages from a common susceptible L. pneumophila ancestral strain were propagated under conditions of erythromycin or azithromycin pressure to produce high-level macrolide resistance. Whole-genome sequencing was performed on 12 selected clones, and we investigated mutations common to all lineages. We reconstructed the dynamics of mutation for each lineage and demonstrated their involvement in decreased susceptibility to macrolides. The resistant mutants were produced in a limited number of passages to obtain a 4,096-fold increase in erythromycin MICs. Mutations affected highly conserved 5-amino-acid regions of L4 and L22 ribosomal proteins and of domain V of 23S rRNA (G2057, A2058, A2059, and C2611 nucleotides). The early mechanisms mainly affected L4 and L22 proteins and induced a 32-fold increase in the MICs of the selector drug. Additional mutations related to 23S rRNA mostly occurred later and were responsible for a major increase of macrolide MICs, depending on the mutated nucleotide, the substitution, and the number of mutated genes among the three rrl copies. The major mechanisms of the decreased susceptibility to macrolides in L. pneumophila and their dynamics were determined. The results showed that macrolide resistance could be easily selected in L. pneumophila and warrant further investigations in both clinical and environmental settings.

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Intrinsic Macrolide Resistance in Mycobacterium smegmatis Is Conferred by a Novel erm Gene, erm(38)

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.47.10.3053-3060.2003 ◽

2003 ◽

Vol 47 (10) ◽

pp. 3053-3060 ◽

Cited By ~ 55

Author(s):

Kevin A. Nash

Keyword(s):

Mycobacterium Smegmatis ◽

Sequence Data ◽

Macrolide Resistance ◽

23S Rrna ◽

Cross Resistance ◽

Rrna Gene ◽

Mycobacterium Fortuitum ◽

Knockout Mutant ◽

23S Rrna Gene ◽

High Level

ABSTRACT High-level, acquired macrolide resistance in mycobacteria is conferred by mutation within the 23S rRNA gene. However, several mycobacteria are naturally resistant to macrolides, including the Mycobacterium smegmatis group and Mycobacterium tuberculosis complex. Thus, the aim of this study was to characterize this resistance. Intrinsic macrolide resistance in M. smegmatis was inducible and showed cross-resistance to lincosamides but not to streptogramin B (i.e., ML resistance). A similar phenotype was found with Mycobacterium microti and macrolide-resistant Mycobacterium fortuitum. A search of the DNA sequence data for M. smegmatis strain mc2155 identified a novel erm gene, erm(38), and expression analysis showed that erm(38) RNA levels increased >10-fold after a 2-h incubation with macrolide. Inducible ML resistance was not expressed by an erm(38) knockout mutant, and complementation of this mutant with intact erm(38) in trans resulted in high-level ML resistance (e.g., clarithromycin MIC of >512 μg/ml). Thus, the results indicate that erm(38) confers the intrinsic ML resistance of M. smegmatis. Southern blot analysis with an erm(38)-specific probe indicated that a similar gene may be present in macrolide-resistant M. fortuitum. This finding, with the presence of the erm(37) gene (Rv1988) in the M. tuberculosis complex, suggests that such genes are widespread in mycobacteria with intrinsic macrolide resistance.

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Antimicrobial susceptibility and mechanisms of high-level macrolide resistance in clinical isolates of Moraxella nonliquefaciens

Journal of Medical Microbiology ◽

10.1099/jmm.0.061788-0 ◽

2014 ◽

Vol 63 (2) ◽

pp. 242-247 ◽

Cited By ~ 6

Author(s):

Shotaro Nonaka ◽

Kosuke Matsuzaki ◽

Tomoya Kazama ◽

Hiroyuki Nishiyama ◽

Yoko Ida ◽

...

Keyword(s):

Antimicrobial Susceptibility ◽

Ribosomal Proteins ◽

Macrolide Resistance ◽

Clinical Isolates ◽

23S Rrna ◽

Rrna Gene ◽

Efflux System ◽

Strong Activity ◽

23S Rrna Gene ◽

High Level

We investigated antimicrobial susceptibility and the molecular mechanism involved in conferring high-level macrolide resistance in 47 clinical isolates of Moraxella nonliquefaciens from Japan. Antimicrobial susceptibility was determined using Etest and agar dilution methods. Thirty-two erythromycin-non-susceptible strains were evaluated for the possibility of clonal spreading, using PFGE. To analyse the mechanism related to macrolide resistance, mutations in the 23S rRNA gene and the ribosomal proteins, and the presence of methylase genes were investigated by PCR and sequencing. The efflux system was examined using appropriate inhibitors. Penicillin, ampicillin, amoxicillin, cefixime, levofloxacin and antimicrobials containing β-lactamase inhibitors showed strong activity against 47 M. nonliquefaciens isolates. Thirty-two (68.1 %) of the 47 isolates showed high-level MICs to macrolides (MIC ≥128 mg l−1) and shared the A2058T mutation in the 23S rRNA gene. The geometric mean MIC to macrolides of A2058T-mutated strains was significantly higher than that of WT strains (P<0.0001). Thirty-two isolates with high-level macrolide MICs clustered into 30 patterns on the basis of the PFGE dendrogram, indicating that the macrolide-resistant strains were not clonal. In contrast, no common mutations of the ribosomal proteins or methylase genes, or overproduction of the efflux system were observed in A2058T-mutated strains. Moreover, of the 47 M. nonliquefaciens strains, 43 (91.5 %) were bro-1 and 4 (8.5 %) were bro-2 positive. Our results suggest that most M. nonliquefaciens clinical isolates show high-level macrolide resistance conferred by the A2058T mutation in the 23S rRNA gene. This study represents the first characterization of M. nonliquefaciens.

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Streptococcus pyogenes Isolates with High-Level Macrolide Resistance and Reduced Susceptibility to Telithromycin Associated with 23S rRNA Mutations

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.50.2.817-818.2006 ◽

2006 ◽

Vol 50 (2) ◽

pp. 817-818 ◽

Cited By ~ 9

Author(s):

David J. Farrell ◽

Jemma Shackcloth ◽

Karen A. Barbadora ◽

Michael D. Green

Keyword(s):

Streptococcus Pyogenes ◽

Macrolide Resistance ◽

23S Rrna ◽

Mlst Type ◽

High Level ◽

Domain V ◽

Reduced Activity

ABSTRACT Seven high-level macrolide-resistant Streptococcus pyogenes isolates had reduced activity to telithromycin but were negative for methylation and efflux genes. All were of the constitutive phenotype, were clonally related (emm type 12 and MLST type 36), and had identical dual mutations (A2058G and U2166C) in domain V of 23S rRNA.

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Paradoxical High-Level Spiramycin Resistance and Erythromycin Susceptibility due to 23S rRNA Mutation in Streptococcus constellatus

Microbial Drug Resistance ◽

10.1089/mdr.2019.0288 ◽

2020 ◽

Vol 26 (7) ◽

pp. 727-731

Author(s):

Agathe Capitaine ◽

Paul-Louis Woerther ◽

Michel Auzou ◽

Elisabeth Chachaty ◽

François Guérin ◽

...

Keyword(s):

23S Rrna ◽

Streptococcus Constellatus ◽

High Level ◽

Rrna Mutation

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Macrolide Resistance–associated 23S rRNA Mutation inMycoplasma genitalium, Japan

Emerging Infectious Diseases ◽

10.3201/eid1706.101055 ◽

2011 ◽

Vol 17 (6) ◽

pp. 1148-1150 ◽

Cited By ~ 38

Author(s):

Yasushi Shimada ◽

Takashi Deguchi ◽

Keita Nakane ◽

Mitsuru Yasuda ◽

Shigeaki Yokoi ◽

...

Keyword(s):

Macrolide Resistance ◽

23S Rrna ◽

Rrna Mutation

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Transferable Multidrug-Resistance Plasmid Carrying a Novel Macrolide-Clindamycin Resistance Gene, erm(50), in Cutibacterium acnes

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01810-19 ◽

2019 ◽

Vol 64 (3) ◽

Author(s):

Sae Aoki ◽

Keisuke Nakase ◽

Hidemasa Nakaminami ◽

Takeaki Wajima ◽

Nobukazu Hayashi ◽

...

Keyword(s):

Resistance Gene ◽

Acne Vulgaris ◽

Tetracycline Resistance ◽

23S Rrna ◽

The Novel ◽

Content Type ◽

Resistance Determinants ◽

Cutibacterium Acnes ◽

High Level ◽

Rrna Mutation

ABSTRACT Antimicrobial-resistant Cutibacterium acnes strains have emerged and disseminated throughout the world. The 23S rRNA mutation and erm(X) gene are known as the major resistance determinants of macrolides and clindamycin in C. acnes. We isolated eight high-level macrolide-clindamycin-resistant C. acnes strains with no known resistance determinants, such as 23S rRNA mutation and erm(X), from different acne patients in 2008 between 2013 and 2015. The aim of this study was to identify the novel mechanisms of resistance in C. acnes. Whole-genome sequencing revealed the existence of a plasmid DNA, denoted pTZC1 (length, 31,440 bp), carrying the novel macrolide-clindamycin resistance gene erm(50) and tetracycline resistance gene tet(W). pTZC1 was detected in all C. acnes isolates (eight strains) exhibiting high-level macrolide-clindamycin resistance, with no known resistance determinants (MIC of clarithromycin, ≥256 μg/ml; clindamycin, ≥256 μg/ml). Transconjugation experiments demonstrated that the pTZC1 was horizontally transferred among C. acnes strains and conferred resistance to macrolides, clindamycin, and tetracyclines. Our data showed, for the first time, the existence of a transferable multidrug-resistant plasmid in C. acnes. Increased prevalence of this plasmid will be a great threat to antimicrobial therapy for acne vulgaris.

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Evaluation of GENECUBE Mycoplasma for the detection of macrolide-resistant Mycoplasma pneumoniae

Journal of Medical Microbiology ◽

10.1099/jmm.0.001264 ◽

2020 ◽

Vol 69 (12) ◽

pp. 1346-1350

Author(s):

Yoshitomo Morinaga ◽

Hiromichi Suzuki ◽

Shigeyuki Notake ◽

Takashi Mizusaka ◽

Keiichi Uemura ◽

...

Keyword(s):

Mycoplasma Pneumoniae ◽

Type Species ◽

Resistance Mutation ◽

Macrolide Resistance ◽

23S Rrna ◽

Molecular Diagnostic ◽

Content Type ◽

Link Type ◽

High Level ◽

Synthetic Oligonucleotides

Introduction. Resistance against macrolide antibiotics in Mycoplasma pneumoniae is becoming non-negligible in terms of both appropriate therapy and diagnostic stewardship. Molecular methods have attractive features for the identification of Mycoplasma pneumoniae as well as its resistance-associated mutations of 23S ribosomal RNA (rRNA). Hypothesis/Gap Statement. The automated molecular diagnostic sytem can identify macrolide-resistant M. pneumoniae . Aim. To assess the performance of an automated molecular diagnostic system, GENECUBE Mycoplasma, in the detection of macrolide resistance-associated mutations. Methodology. To evaluate whether the system can distinguish mutant from wild-type 23S rRNA, synthetic oligonucleotides mimicking known mutations (high-level macrolide resistance, mutation in positions 2063 and 2064; low-level macrolide resistance, mutation in position 2067) were assayed. To evaluate clinical oropharyngeal samples, purified nucleic acids were obtained from M. pneumoniae -positive samples by using the GENECUBE system from nine hospitals. After confirmation by re-evaluation of M. pneumoniae positivity, Sanger-based sequencing of 23S rRNA and mutant typing using GENECUBE Mycoplasma were performed. Results. The system reproducibly identified all synthetic oligonucleotides associated with high-level macrolide resistance. Detection errors were only observed for A2067G (in 2 of the 10 measurements). The point mutation in 23S rRNA was detected in 67 (26.9 %) of 249 confirmed M. pneumoniae -positive clinical samples. The mutations at positions 2063, 2064 and 2617 were observed in 65 (97.0 %), 2 (3.0 %) and 0 (0.0 %) of the 67 samples, respectively. The mutations at positions 2063 and 2064 were A2063G and A2064G, respectively. The results from mutant typing using GENECUBE Mycoplasma were in full agreement with the results from sequence-based typing. Conclusion. GENECUBE Mycoplasma is a reliable test for the identification of clinically significant macrolide-resistant M. pneumoniae .

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