Genetic Alternatives for Experimental Adaptation to Colistin in Three <i>Pseudomonas aeruginosa</i> Lineages

• Main Authors: Igor Chebotar (Author), Tatiana Savinova (Author), Julia Bocharova (Author), Dmitriy Korostin (Author), Peter Evseev (Author), Nikolay Mayanskiy (Author)
• Format: Book
• Published: MDPI AG, 2024-05-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.

Summary

<i>Pseudomonas aeruginosa</i> is characterized by a high adaptive potential, developing resistance in response to antimicrobial pressure. We employed a spatiotemporal evolution model to disclose the pathways of adaptation to colistin, a last-resort polymyxin antimicrobial, among three unrelated <i>P. aeruginosa</i> lineages. The <i>P. aeruginosa</i> ATCC-27833 reference strain (<i>Pa_ATCC</i>), an environmental <i>P. aeruginosa</i> isolate (<i>Pa_Environment</i>), and a clinical isolate with multiple drug resistance (<i>Pa_MDR</i>) were grown over an increasing 5-step colistin concentration gradient from 0 to 400 mg/L. <i>Pa_Environment</i> demonstrated the highest growth pace, achieving the 400 mg/L band in 15 days, whereas it took 37 and 60 days for <i>Pa_MDR</i> and <i>Pa_ATCC</i>, respectively. To identify the genome changes that occurred during adaptation to colistin, the isolates selected during the growth of the bacteria (<i>n</i> = 185) were subjected to whole genome sequencing. In total, 17 mutation variants in eight lipopolysaccharide-synthesis-associated genes were detected. <i>phoQ</i> and <i>lpxL</i>/PA0011 were affected in all three lineages, whereas changes in <i>pmrB</i> were found in <i>Pa_Environment</i> and <i>Pa_MDR</i> but not in <i>Pa_ATCC</i>. In addition, mutations were detected in 34 general metabolism genes, and each lineage developed mutations in a unique set of such genes. Thus, the three examined distinct <i>P. aeruginosa</i> strains demonstrated different capabilities and genetic pathways of colistin adaptation.

Item Description

10.3390/antibiotics13050452
2079-6382