Bogdan Maja, Drenjancevic Domagoj, Harsanji Drenjancevic Ivana, Bedenic Branka, Zujic Atalic Vlasta, Talapko Jasminka, Vukovic Dubravka
a Microbiology Service , Institute of Public Health Osijek-Baranja County , Osijek , Croatia.
b Faculty of Medicine, Department of Microbiology and Parasitology , University of Osijek , Osijek , Croatia.
J Chemother. 2018 Feb;30(1):16-24. doi: 10.1080/1120009X.2017.1378835. Epub 2017 Sep 28.
The ability of A cinetobacter baumannii strains to form biofilm is one of the most important virulence factor which enables bacterial survival in a harsh environment and decreases antibiotic concentration as well. Subminimal inhibitory concentrations (subMICs) of antibiotics may change bacterial ultrastructure or have an influence on some different molecular mechanisms resulting in morphological or physiological changes in bacteria itself. The aim of this study was to determine effects of 1/2, 1/4, 1/8 and 1/16 minimal inhibitory concentrationsof imipenem, ampicillin-sulbactam, azithromycin, rifampicin and colistin on biofilm formation ability of 22 biofilm non-producing and 46 biofilm producing A. baumannii strains (30 weak producing strains and 16 moderate producing strains). Results of this study indicate that 1/2-1/16 MICs of imipenem, azithromycin, and rifampicin can reduce bacterial biofilm formation ability in moderate producing strains (p < 0.05), whereas 1/16 MIC of imipenem and 1/4-1/8 MICs of rifampicin reduce the biofilm formation in weak producing strains (p < 0.05). Statisticaly significant effect was detected among biofilm non-producing strains after their exposure to 1/16 MIC of azithromycin (p = 0.039). SubMICs of ampicillin-sulbactam and colistin did not have any significant effect on biofilm formation among tested A. baumannii strains.
鲍曼不动杆菌菌株形成生物膜的能力是最重要的毒力因子之一，它能使细菌在恶劣环境中存活，还能降低抗生素浓度。抗生素的亚最小抑菌浓度（subMICs）可能会改变细菌的超微结构，或对一些不同的分子机制产生影响，从而导致细菌自身的形态或生理变化。本研究的目的是确定亚胺培南、氨苄西林-舒巴坦、阿奇霉素、利福平及黏菌素的1/2、1/4、1/8和1/16最小抑菌浓度对22株不产生物膜和46株产生物膜的鲍曼不动杆菌菌株（30株弱产菌株和16株中产菌株）生物膜形成能力的影响。本研究结果表明，亚胺培南、阿奇霉素和利福平的1/2 - 1/16 MICs可降低中产菌株的细菌生物膜形成能力（p < 0.05），而亚胺培南的1/16 MIC和利福平的1/4 - 1/8 MICs可降低弱产菌株的生物膜形成能力（p < 0.05）。在不产生物膜的菌株暴露于1/16 MIC的阿奇霉素后，检测到有统计学意义的效应（p = 0.039）。氨苄西林-舒巴坦和黏菌素的亚MICs对受试鲍曼不动杆菌菌株的生物膜形成没有任何显著影响。
