Adaptive Interactions of Achromobacter spp. with Pseudomonas aeruginosa in Cystic Fibrosis Chronic Lung Co-Infection

Abstract

In the lungs of patients with cystic fibrosis (CF), the main pathogen Pseudomonas aeruginosa is often co-isolated with other microbes, likely engaging in inter-species interactions. In the case of chronic co-infections, this cohabitation can last for a long time and evolve over time, potentially contributing to the clinical outcome. Interactions involving the emerging pathogens Achromobacter spp. have only rarely been studied, reporting inhibition of P. aeruginosa biofilm formation. To evaluate the possible evolution of such interplay, we assessed the ability of Achromobacter spp. isolates to affect the biofilm formation of co-isolated P. aeruginosa strains during long-term chronic co-infections. We observed both competition and cohabitation. An Achromobacter sp. isolate secreted exoproducts interfering with the adhesion ability of a co-isolated P. aeruginosa strain and affected its biofilm formation. Conversely, a clonal Achromobacter sp. strain later isolated from the same patient, as well as two longitudinal strains from another patient, did not show similar competitive behavior against its P. aeruginosa co-isolates. Genetic variants supporting the higher virulence of the competitive Achromobacter sp. isolate were found in its genome. Our results confirm that both inter-species competition and cohabitation are represented during chronic co-infections in CF airways, and evolution of these interplays can happen even at the late stages of chronic infection.

Achromobacter spp. Adaptation in Cystic Fibrosis Infection and Candidate Biomarkers of Antimicrobial Resistance

“…Although no significant difference in biofilm production was observed between chronic and occasional isolates nor between early and late chronic isolates, the great majority of strains unable to form biofilm were isolated from chronic infection. This could suggest a mechanism of within-host adaptation in the CF lung; e.g., acquisition of mutations in genes with a role in surface adhesion could lead to decreased biofilm production or to formation of unattached aggregates [ 10 , 13 , 19 ].…”

Enigmatic Achromobacter

“…Часто представители Achromobacter spp. являются соу частниками полимикробного инфекционного процесса, в реализации которого они прекрасно уживаются с са мыми разнообразными представителями прокариот и грибов [93][94][95].…”

Polymyxin Resistance and Heteroresistance Are Common in Clinical Isolates of Achromobacter Species and Correlate with Modifications of the Lipid A Moiety of Lipopolysaccharide

“…High-level intrinsic resistance is compounded by the acquisition of metallo-β-lactamases via mobile genetic elements, conferring resistance to carbapenems ( 38 , 39 ), and can be further enhanced by chronic infection ( 36 ). Frequent coisolation with Pseudomonas aeruginosa in pwCF reduces the choices of antibiotics with efficacy against both genera ( 40 , 41 ).…”