Adaptive response of single and binary Pseudomonas aeruginosa and Escherichia coli biofilms to benzalkonium chloride

• Type: Article in International Scientific Journal
• Date: 2012

Authors

Idalina Machado (Author) Other; Lopes, SP (Author) Other; Sousa, AM (Author) Other; Pereira, MO (Author) Other

Journal

Title: Journal of Basic Microbiology

Vol. 52

Pages: 43-52

ISSN: 0233-111X

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 14 Citations

Scopus - 11 Citations

Other information

Authenticus ID: P-002-DAR

DOI: 10.1002/jobm.201100137

Abstract (EN): The main goal of this work was to examine whether the continuous exposure of single and binary P. aeruginosa and E. coli biofilms to sub-lethal benzalkonium chloride (BC) doses can induce adaptive response of bacteria. Biofilms were formed during 24 h and then put continuously in contact with BC for more 5 days. The six-day-old adapted biofilms were then submitted to BC challenge, characterized and inspected by SEM. Both single and binary adapted biofilms have clearly more biomass, polysaccharides and proteins and less activity even though the number of cells was identical. After BC treatment, adapted biofilms maintained their mass and activity. SEM examination revealed that those adapted biofilms had a slimier and denser matrix that became thicker after BC treatment. Continuous exposure of bacteria to antimicrobials can lead to development of biofilms encompassing more virulent and tolerant bacteria. This adaptive resistance can be the result of a phenotypic adaptation, a genetic acquired resistance or both. Instead of eradicating biofilms and kill microorganisms, the use of a disinfectant can, favour biofilm formation and tolerance. This must be a genuine concern as it can happen in clinical environments, where the use of antimicrobials is unavoidable. ((c) 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10