Microbial Genetics, Institute of Microbiology and Infection Medicine Tübingen, University of Tübingen, Tübingen, Germany.
Antimicrob Agents Chemother. 2012 Nov;56(11):5804-10. doi: 10.1128/AAC.01296-12. Epub 2012 Aug 27.
Due to their abilities to form strong biofilms, Staphylococcus aureus and Staphylococcus epidermidis are the most frequently isolated pathogens in persistent and chronic implant-associated infections. As biofilm-embedded bacteria are more resistant to antibiotics and the immune system, they are extremely difficult to treat. Therefore, biofilm-active antibiotics are a major challenge. Here we investigated the effect of the lantibiotic gallidermin on two representative biofilm-forming staphylococcal species. Gallidermin inhibits not only the growth of staphylococci in a dose-dependent manner but also efficiently prevents biofilm formation by both species. The effect on biofilm might be due to repression of biofilm-related targets, such as ica (intercellular adhesin) and atl (major autolysin). However, gallidermin's killing activity on 24-h and 5-day-old biofilms was significantly decreased. A subpopulation of 0.1 to 1.0% of cells survived, comprising "persister" cells of an unknown genetic and physiological state. Like many other antibiotics, gallidermin showed only limited activity on cells within mature biofilms.
由于金黄色葡萄球菌和表皮葡萄球菌能够形成强大的生物膜，因此它们是持续性和慢性植入物相关感染中最常分离到的病原体。由于生物膜内的细菌对抗生素和免疫系统的抵抗力更强，因此治疗起来极其困难。因此，生物膜活性抗生素是一个主要的挑战。在这里，我们研究了羊毛硫肽类抗生素加替沙星对两种具有代表性的生物膜形成的葡萄球菌的影响。加替沙星不仅能以剂量依赖的方式抑制葡萄球菌的生长，而且还能有效地防止两种细菌形成生物膜。这种对生物膜的作用可能是由于抑制了生物膜相关的靶标，如ica（细胞间黏附素）和 atl（主要自溶素）。然而，加替沙星对 24 小时和 5 天龄生物膜的杀菌活性显著降低。有 0.1%到 1%的细胞存活下来，其中包含了未知遗传和生理状态的“持久生存”细胞。像许多其他抗生素一样，加替沙星对成熟生物膜内的细胞仅显示出有限的活性。
