Division of Antimicrobial Resistance, Center for Infectious Disease, National Institute of Health, Korea Center for Disease Control and Prevention (KCDC), 194, Tongil-Lo, Eunpyung-Gu, Seoul, 122-701, Republic of Korea.
Diagn Microbiol Infect Dis. 2011 May;70(1):112-8. doi: 10.1016/j.diagmicrobio.2010.11.018. Epub 2011 Mar 12.
The purpose of this study was to quantify the biofilm formations of various methicillin-resistant Staphylococcus aureus (MRSA) clones (ST1, ST5, ST72, ST89, ST239, and ST254) and to evaluate the in vitro activities of antibiotics. Of 86 MRSA isolates tested, 44 isolates (51.2 %) formed biofilms, including 8 strong biofilm producers (7 isolates of ST72 and 1 isolate of ST89). The planktonic MICs, minimal bactericidal concentrations, and minimum biofilm eradication concentrations (MBECs) of 6 antibiotics (clindamycin, gentamicin, linezolid, vancomycin, daptomycin, and tigecycline) were measured for 8 MRSA isolates. The planktonic isolates were susceptible to all agents, with daptomycin being the most effective, followed by gentamicin and vancomycin. However, clindamycin, linezolid, and tigecycline showed bacteriostatic activity against most of the isolates. The biofilms were resistant to high concentrations of most drugs. However, the MBEC values of daptomycin and tigecycline were lower overall than that of other antibiotics. Microscopy studies verified that daptomycin was the most effective drug used in adhesive biofilms, while gentamicin and tigecycline exhibited some bactericidal efficacy. Our results demonstrated that ST72 and ST89 form strong biofilms that may cause problems in hospital setting, and daptomycin, gentamicin, and tigecycline may be choice therapeutics against biofilm-mediated S. aureus infections.
本研究旨在定量检测不同耐甲氧西林金黄色葡萄球菌 (MRSA) 克隆（ST1、ST5、ST72、ST89、ST239 和 ST254）的生物膜形成情况，并评估抗生素的体外活性。在测试的 86 株 MRSA 分离株中，有 44 株（51.2%）形成了生物膜，其中包括 8 株强生物膜生产者（7 株 ST72 和 1 株 ST89）。对 8 株 MRSA 分离株的 6 种抗生素（克林霉素、庆大霉素、利奈唑胺、万古霉素、达托霉素和替加环素）的浮游 MIC、最低杀菌浓度和最低生物膜清除浓度（MBEC）进行了测量。浮游分离株对所有药物均敏感，达托霉素最有效，其次是庆大霉素和万古霉素。然而，克林霉素、利奈唑胺和替加环素对大多数分离株表现出抑菌活性。生物膜对大多数药物的高浓度均有耐药性。然而，达托霉素和替加环素的 MBEC 值总体上低于其他抗生素。显微镜研究证实，达托霉素是抗黏附生物膜最有效的药物，而庆大霉素和替加环素则表现出一定的杀菌效果。我们的研究结果表明，ST72 和 ST89 形成的强生物膜可能会在医院环境中引发问题，而达托霉素、庆大霉素和替加环素可能是治疗生物膜介导的金黄色葡萄球菌感染的选择治疗药物。
