Microbial interaction between a CTXM-15-producing Escherichia coli and a susceptible Pseudomonas aeruginosa isolated from bronchoalveolar lavage: influence of cefotaxime in the dual-species biofilm formation

• Type: Article in International Scientific Journal
• Date: 2015

Authors

Lucinda J Bessa (Author) Other; Angelo Mendes (Author) Other; Rita Gomes (Author) Other; Sara Curvelo (Author) Other; Sara Cravo (Author) Other; Emilia Sousa (Author) Other; Vitor Vasconcelos (Author) FCUP; Paulo Martins da Costa (Author) Other

Journal

Title: Environmental Microbiology Reports

Vol. 7

Pages: 420-426

ISSN: 1758-2229

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 1 Citation

Scopus - 1 Citation

Scientific classification

FOS: Natural sciences > Earth and related Environmental sciences

Other information

Authenticus ID: P-00G-46G

DOI: 10.1111/1758-2229.12266

Abstract (EN): Two isolates, Escherichia coli ella00 and Pseudomonas aeruginosa ella01, obtained from bronchoalveolar lavage, were found to be closely associated in clusters in agar medium. Escherichia coli ella00 was multidrug resistant and CTXM-15 extended-spectrum -lactamase producer, while P.aeruginosa ella01 was susceptible to all antimicrobials tested. These observations impelled for further studies aimed to understand their microbial interaction. The P.aeruginosa ella01 biofilm-forming capacity was reduced and not affected when it was co-cultured with E.coli ella00 and E.coliATCC 25922 respectively. Interestingly, the co-culture of ella isolates in the presence of high concentrations, such as 160 gml(-1), of cefotaxime allowed the formation of more biofilm than in the absence of the antibiotic. As revealed by fluorescence in situ hybridization, in co-culture, P.aeruginosa ella01 survived and subsequently flourished when exposed to this third-generation cephalosporin at a concentration 10xhigher than its minimum inhibitory concentration (MIC), and this was mostly due to -lactamases production by E.coli ella00. In fact, it was demonstrated by high-performance liquid chromatography that cefotaxime was absent for the culture medium 4h after application. In conclusion, we demonstrate that bacterial species can interact differently depending on the surrounding conditions (favourable or stressing), and that those interactions can switch from unprofitable to beneficial.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 7