Abstract Detection of pathogenic Legionella pneumophila by culture-based methods is not efficient in predicting outbreaks of the Legionnaires’ disease. The main problem is the relatively slow time-to-result and the inability of some culture media to support the growth of viable bacteria. One strategy to alleviate these issues is developing biosensors functionalized with mammalian antibodies designed to capture bacteria. However, mammalian antibodies are known to suffer from batch-to-batch variations, as well as limited stability, which reduce the consistent utility of antibody-based biosensors. In an attempt to address this problem, we investigated antimicrobial peptides (AMPs) for capture of L. pneumophila with GaAs/AlGaAs biochips. The Fourier-transform infrared spectroscopy measurements revealed that the peptides were covalently immobilized on the 1-ethyl-3-(-3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide activated −COOH terminals of mercaptohexadecanoic acid self-assembled monolayer functionalized GaAs surface. The efficiency of the specific interaction between the peptide and L. pneumophila, E. coli, B. subtilis and P. fluorescens was investigated with fluorescence microscopy and a digital photocorrosion GaAs/AlGaAs biosensor. We found that the warnericin RK peptides exhibited ∼5 times greater binding affinity towards L. pneumophila than to the other bacteria investigated. Furthermore, detection level as low as 103 CFU/mL was possible with the proposed biosensor architecture. We argue that a biosensor based on warnericin RK AMP peptides offers an attractive alternative solution in comparison to antibody-based devices towards detection of L. pneumophila.

中文翻译：

---

抗菌华纳霉素 RK 肽功能化 GaAs/AlGaAs 生物传感器，用于高灵敏度和选择性检测嗜肺军团菌

摘要 通过基于培养的方法检测致病性嗜肺军团菌在预测军团病爆发方面效率不高。主要问题是获得结果的时间相对较慢，并且某些培养基无法支持活细菌的生长。缓解这些问题的一种策略是开发用哺乳动物抗体功能化的生物传感器，这些抗体旨在捕获细菌。然而，众所周知，哺乳动物抗体存在批次间差异以及稳定性有限的问题，这降低了基于抗体的生物传感器的一致效用。为了解决这个问题，我们研究了用 GaAs/AlGaAs 生物芯片捕获嗜肺军团菌的抗菌肽 (AMP)。傅里叶变换红外光谱测量显示肽共价固定在巯基十六烷酸自组装单层功能化 GaAs 表面的 1-乙基-3-(-3-二甲基氨基丙基)碳二亚胺/N-羟基琥珀酰亚胺活化的-COOH 末端。用荧光显微镜和数字光腐蚀 GaAs/AlGaAs 生物传感器研究了肽与嗜肺军团菌、大肠杆菌、枯草芽孢杆菌和荧光假单胞菌之间特定相互作用的效率。我们发现，warnericin RK 肽对 L. pneumophila 的结合亲和力比对其他研究的细菌高约 5 倍。此外，所提出的生物传感器架构可实现低至 103 CFU/mL 的检测水平。