Department of Chemical Science, University of Naples "Federico II", Via Cinthia, 80126 Naples, Italy.
Division of Chemical Technology, School of Chemistry, Aristotle University of Thessaloniki, University Box 116, 54 124 Thessaloniki, Greece.
Int J Mol Sci. 2020 Nov 12;21(22):8526. doi: 10.3390/ijms21228526.
Biofilms consist of a complex microbial community adhering to biotic or abiotic surfaces and enclosed within a protein/polysaccharide self-produced matrix. The formation of this structure represents the most important adaptive mechanism that leads to antibacterial resistance, and therefore, closely connected to pathogenicity. Antimicrobial peptides (AMPs) could represent attractive candidates for the design of new antibiotics because of their specific characteristics. AMPs show a broad activity spectrum, a relative selectivity towards their targets (microbial membranes), the ability to act on both proliferative and quiescent cells, a rapid mechanism of action, and above all, a low propensity for developing resistance. This article investigates the effect at subMIC concentrations of Temporin-L (TL) on biofilm formation in () both in static and dynamic conditions, showing that TL displays antibiofilm properties. Biofilm formation in static conditions was analyzed by the Crystal Violet assay. Investigation of biofilms in dynamic conditions was performed in a commercial microfluidic device consisting of a microflow chamber to simulate real flow conditions in the human body. Biofilm morphology was examined using Confocal Laser Scanning Microscopy and quantified via image analysis. The investigation of TL effects on showed that when subMIC concentrations of this peptide were added during bacterial growth, TL exerted antibiofilm activity, impairing biofilm formation both in static and dynamic conditions. Moreover, TL also affects mature biofilm as confocal microscopy analyses showed that a large portion of preformed biofilm architecture was clearly perturbed by the peptide addition with a significative decrease of all the biofilm surface properties and the overall biomass. Finally, in these conditions, TL did not affect bacterial cells as the live/dead cell ratio remained unchanged without any increase in damaged cells, confirming an actual antibiofilm activity of the peptide.
生物膜由附着在生物或非生物表面的复杂微生物群落组成，并被自身产生的蛋白质/多糖基质所包裹。这种结构的形成代表了导致抗菌耐药性的最重要适应机制，因此与致病性密切相关。抗菌肽 (AMP) 因其独特的特性而可能成为设计新型抗生素的有吸引力的候选物。AMP 具有广谱活性、对其靶标（微生物膜）的相对选择性、对增殖和静止细胞均有作用的能力、快速的作用机制，最重要的是，它们不易产生耐药性。本文研究了亚最小抑菌浓度 (subMIC) 的 Temporin-L (TL) 对 （）在静态和动态条件下生物膜形成的影响，结果表明 TL 具有抗生物膜特性。静态条件下的生物膜形成通过结晶紫测定法进行分析。在商业微流控装置中进行动态条件下生物膜的研究，该装置由微流室组成，以模拟人体中的真实流动条件。使用共聚焦激光扫描显微镜检查生物膜形态，并通过图像分析进行定量。研究 TL 对 的影响表明，当亚 MIC 浓度的这种肽添加到细菌生长过程中时，TL 发挥了抗生物膜活性，在静态和动态条件下均损害了生物膜的形成。此外，TL 还影响成熟的生物膜，因为共聚焦显微镜分析表明，预先形成的生物膜结构的大部分明显受到肽添加的干扰，所有生物膜表面特性和整体生物量均显著减少。最后，在这些条件下，TL 不会影响细菌细胞，因为活/死细胞比保持不变，没有增加受损细胞，证实了肽的实际抗生物膜活性。
