Department of Microsystems Engineering (IMTEK)-Laboratory of Sensors, University of Freiburg, 79110 Freiburg, Germany.
Institute of Microbiology and Epizootics, Freie Universität Berlin, 14163 Berlin, Germany.
Sensors (Basel). 2021 Apr 14;21(8):2771. doi: 10.3390/s21082771.
The increasing rate of antimicrobial resistance (AMR) in pathogenic bacteria is a global threat to human and veterinary medicine. Beyond antibiotics, antimicrobial peptides (AMPs) might be an alternative to inhibit the growth of bacteria, including AMR pathogens, on different surfaces. Biofilm formation, which starts out as bacterial adhesion, poses additional challenges for antibiotics targeting bacterial cells. The objective of this study was to establish a real-time method for the monitoring of the inhibition of (a) bacterial adhesion to a defined substrate and (b) biofilm formation by AMPs using an innovative thermal sensor. We provide evidence that the thermal sensor enables continuous monitoring of the effect of two potent AMPs, protamine and OH-CATH-30, on surface colonization of bovine mastitis-associated () and () . The bacteria were grown under static conditions on the surface of the sensor membrane, on which temperature oscillations generated by a heater structure were detected by an amorphous germanium thermistor. Bacterial adhesion, which was confirmed by white light interferometry, caused a detectable amplitude change and phase shift. To our knowledge, the thermal measurement system has never been used to assess the effect of AMPs on bacterial adhesion in real time before. The system could be used to screen and evaluate bacterial adhesion inhibition of both known and novel AMPs.
抗菌药物耐药性（AMR）在致病菌中的发生率不断上升，这是对人类和兽医医学的全球性威胁。除了抗生素之外，抗菌肽（AMPs）可能是一种替代方法，可以抑制包括 AMR 病原体在内的细菌在不同表面上的生长。生物膜的形成始于细菌黏附，这给针对细菌细胞的抗生素带来了额外的挑战。本研究的目的是建立一种实时方法，利用创新的热传感器监测（a）抗菌肽对特定基质上细菌黏附的抑制作用和（b）生物膜形成。我们提供的证据表明，热传感器能够连续监测两种有效 AMP（鱼精蛋白和 OH-CATH-30）对牛乳腺炎相关（）和（）表面定植的影响。细菌在传感器膜表面的静态条件下生长，加热器结构产生的温度振荡由非晶态锗热敏电阻检测。通过白光干涉测量法证实了细菌黏附，这导致了可检测的幅度变化和相位偏移。据我们所知，热测量系统以前从未用于实时评估 AMP 对抗菌黏附的影响。该系统可用于筛选和评估已知和新型 AMP 对细菌黏附的抑制作用。
