Journal
WORLD JOURNAL OF MICROBIOLOGY & BIOTECHNOLOGY
Volume 30, Issue 12, Pages 3015-3025Publisher
SPRINGER
DOI: 10.1007/s11274-014-1728-7
Keywords
Antimicrobial activity; Biofilms; Imipenem; Rifampicin; Synergy
Categories
Funding
- National Nature Science Foundation of China [31172364, 31271951, 31000822]
- Program for New Century Excellent Talents in University [NCET-09-0434, NCET-13-0245]
- Fundamental Research Program of Shen Zhen [JCYJ20130401172016183, JCYJ20120616 142424467]
- Shenzhen Promotion Plan Basic Research Laboratory [ZDSY20120616141302982]
Ask authors/readers for more resources
To investigate the antimicrobial activity of imipenem and rifampicin alone and in combination against clinical isolates of Acinetobacter baumannii grown in planktonic and biofilm cultures. Minimum inhibitory concentrations were determined for each isolate grown in suspension and in biofilm using a microbroth dilution method. Chequerboard assays and the agar disk diffusion assay were used to determine synergistic, indifferent or antagonistic interactions between imipenem and rifampicin. We used the tissue culture plate method for A. baumannii biofilm formation to measure the percentage of biofilm inhibition and the amount of extracellular DNA after the treatment. To understand the synergistic mechanisms, we conducted hydroxyl radical formation assays. The results were verified by confocal laser scanning microscopy. Imipenem and rifampicin showed effective antimicrobial activity against suspensions and biofilm cultures of A. baumannii, respectively. Synergistic antimicrobial effects between imipenem and rifampicin were observed in 13 and 17 of the 20 clinical isolates when in suspension and in biofilms, respectively. Imipenem and rifampicin alone and in combination generated hydroxyl radicals, which are highly reactive oxygen forms and the major components of bactericidal agents. Furthermore, treatment with imipenem and rifampicin individually or in combination has obvious antibiofilm effects. The synergistic activity of imipenem and rifampicin against clinical isolates of A. baumannii (in suspension and in biofilms) was observed in vitro. Therefore, we conclude that imipenem combined with rifampicin has the potential to be used as a combinatorial therapy for the treatment of infectious diseases caused by A. baumannii.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available