Dataset Information

Colistin-degrading proteases confer collective resistance to microbial communities during polymicrobial infections.

ABSTRACT:

Background

The increasing prevalence of resistance against the last-resort antibiotic colistin is a significant threat to global public health. Here, we discovered a novel colistin resistance mechanism via enzymatic inactivation of the drug and proposed its clinical importance in microbial communities during polymicrobial infections.

Results

A bacterial strain of the Gram-negative opportunistic pathogen Stenotrophomonas maltophilia capable of degrading colistin and exhibiting a high-level colistin resistance was isolated from the soil environment. A colistin-degrading protease (Cdp) was identified in this strain, and its contribution to colistin resistance was demonstrated by growth inhibition experiments using knock-out (Δcdp) and complemented (Δcdp::cdp) mutants. Coculture and coinfection experiments revealed that S. maltophilia carrying the cdp gene could inactivate colistin and protect otherwise susceptible Pseudomonas aeruginosa, which may seriously affect the clinical efficacy of the drug for the treatment of cystic fibrosis patients with polymicrobial infection.

Conclusions

Our results suggest that Cdp should be recognized as a colistin resistance determinant that confers collective resistance at the microbial community level. Our study will provide vital information for successful clinical outcomes during the treatment of complex polymicrobial infections, particularly including S. maltophilia and other colistin-susceptible Gram-negative pathogens such as P. aeruginosa. Video abstract.

SUBMITTER: Lee DH

PROVIDER: S-EPMC9389796 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature

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Publications

Colistin-degrading proteases confer collective resistance to microbial communities during polymicrobial infections.

Lee Do-Hoon DH Cha Ju-Hee JH Kim Dae-Wi DW Lee Kihyun K Kim Yong-Seok YS Oh Hyo-Young HY Cho You-Hee YH Cha Chang-Jun CJ

Microbiome 20220819 1

<h4>Background</h4>The increasing prevalence of resistance against the last-resort antibiotic colistin is a significant threat to global public health. Here, we discovered a novel colistin resistance mechanism via enzymatic inactivation of the drug and proposed its clinical importance in microbial communities during polymicrobial infections.<h4>Results</h4>A bacterial strain of the Gram-negative opportunistic pathogen Stenotrophomonas maltophilia capable of degrading colistin and exhibiting a hi ...[more]

PMID: 35982474

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Dataset Information

Colistin-degrading proteases confer collective resistance to microbial communities during polymicrobial infections.

Background

Results

Conclusions

Publications

Colistin-degrading proteases confer collective resistance to microbial communities during polymicrobial infections.

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