<abstract xmlns="http://www.w3.org/1999/xhtml"><p>In analyzing the drug resistance phenotype and mechanism of resistance to macrolide antibiotics of clinical <italic>Pseudomonas aeruginosa</italic> isolates, the agar dilution method was used to determine the minimum inhibitory concentrations (MICs), and PCR (polymerase chain reaction) was applied to screen for macrolide antibiotics resistance genes. The macrolide antibiotics resistance genes were cloned, and their functions were identified. Of the 13 antibiotics tested, <italic>P. aeruginosa</italic> strains showed high resistance rates (ranging from 69.5–82.1%), and MIC levels (MIC90 > 256 μg/ml) to macrolide antibiotics. Of the 131 known macrolide resistance genes, only two genes, <italic>mphE</italic> and <italic>msrE</italic>, were identified in 262 clinical <italic>P. aeruginosa</italic> isolates. Four strains (1.53%, 4/262) carried both the <italic>msrE</italic> and <italic>mphE</italic> genes, and an additional three strains (1.15%, 3/262) harbored the <italic>mphE</italic> gene alone. The cloned <italic>msrE</italic> and <italic>mphE</italic> genes conferred higher resistance levels to three second-generation macrolides compared to two first-generation ones. Analysis of MsrE and MphE protein polymorphisms revealed that they are highly conserved, with only 1–3 amino acids differences between the proteins of the same type. It can be concluded that even though the strains showed high resistance levels to macrolides, known macrolide resistance genes are seldom present in clinical <italic>P. aeruginosa</italic> strains, demonstrating that a mechanism other than this warranted by the <italic>mphE</italic> and <italic>msrE</italic> genes may play a more critical role in the bacteria’s resistance to macrolides.</p></abstract>

In analyzing the drug resistance phenotype and mechanism of resistance to macrolide antibiotics of clinical Pseudomonas aeruginosa isolates, the agar dilution method was used to determine the minimum inhibitory concentrations (MICs), and PCR (polymerase chain reaction) was applied to screen for macrolide antibiotics resistance genes. The macrolide antibiotics resistance genes were cloned, and their functions were identified. Of the 13 antibiotics tested, P. aeruginosa strains showed high resistance rates (ranging from 69.5–82.1%), and MIC levels (MIC90 > 256 μg/ml) to macrolide antibiotics. Of the 131 known macrolide resistance genes, only two genes, mphE and msrE, were identified in 262 clinical P. aeruginosa isolates. Four strains (1.53%, 4/262) carried both the msrE and mphE genes, and an additional three strains (1.15%, 3/262) harbored the mphE gene alone. The cloned msrE and mphE genes conferred higher resistance levels to three second-generation macrolides compared to two first-generation ones. Analysis of MsrE and MphE protein polymorphisms revealed that they are highly conserved, with only 1–3 amino acids differences between the proteins of the same type. It can be concluded that even though the strains showed high resistance levels to macrolides, known macrolide resistance genes are seldom present in clinical P. aeruginosa strains, demonstrating that a mechanism other than this warranted by the mphE and msrE genes may play a more critical role in the bacteria’s resistance to macrolides.

Characterization of Two Macrolide Resistance-Related Genes in Multidrug-Resistant <italic>Pseudomonas aeruginosa</italic> Isolates

Polish Journal of Microbiology

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Characterization of Two Macrolide Resistance-Related Genes in Multidrug-Resistant  Isolates

In analyzing the drug resistance phenotype and mechanism of resistance to macrolide antibiotics of clinical Pseudomonas aeruginosa isolates, the agar dilution...

Characterization of Two Macrolide Resistance-Related Genes in Multidrug-Resistant Pseudomonas aeruginosa Isolates

Article Category: original-paper

Pubblicato online: 08 set 2020

Pagine: 349 - 356

Ricevuto: 14 mag 2020

Accettato: 15 ago 2020

DOI: https://doi.org/10.33073/pjm-2020-038

Parole chiave
macrolide, resistance gene,

© 2020 Qing Chen et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Characterization of Two Macrolide Resistance-Related Genes in Multidrug-Resistant Pseudomonas aeruginosa Isolates

Article Category: original-paper

Pubblicato online: 08 set 2020

Pagine: 349 - 356

Ricevuto: 14 mag 2020

Accettato: 15 ago 2020

DOI: https://doi.org/10.33073/pjm-2020-038

Parole chiavemacrolide, resistance gene,

© 2020 Qing Chen et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Parole chiave
macrolide, resistance gene,