Hong Wei, Nyaruaba Raphael, Li Xiaohong, Liu Huan, Yang Hang, Wei Hongping
CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan, China.
College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China.
Front Microbiol. 2021 Nov 30;12:783472. doi: 10.3389/fmicb.2021.783472. eCollection 2021.
can produce a multilayered biofilm embedded in extracellular polymeric matrix. This biofilm is difficult to remove, insensitive to antibiotics, easy to develop drug-resistant strains and causes enormous problems to environments and health. Phage lysin which commonly consists of a catalytic domain (CD) and a cell-wall binding domain (CBD) is a powerful weapon against bacterial biofilm. However, the real-time interaction between lysin and biofilm is still not fully understood. In this study, we monitored the interactions of three lysins (ClyF, ClyC, PlySs2) against culture-on-chip biofilm, in real-time, based on surface plasmon resonance (SPR). A typical SPR response curve showed that the lysins bound to the biofilm rapidly and the biofilm destruction started at a longer time. By using 1:1 binding model analysis, affinity constants ( ) for ClyF, ClyC, and PlySs2 were found to be 3.18 ± 0.127 μM, 1.12 ± 0.026 μM, and 15.5 ± 0.514 μM, respectively. The fact that ClyF and PlySs2 shared the same CBD but showed different affinity to biofilm suggested that, not only CBD, but also CD affects the binding activity of the entire lysin. The SPR platform can be applied to improve our understanding on the complex interactions between lysins and bacterial biofilm including association (adsorption) and disassociation (destruction).
能够产生嵌入细胞外聚合物基质中的多层生物膜。这种生物膜难以去除，对抗生素不敏感，容易产生耐药菌株，给环境和健康带来巨大问题。噬菌体裂解酶通常由催化结构域（CD）和细胞壁结合结构域（CBD）组成，是对抗细菌生物膜的有力武器。然而，裂解酶与生物膜之间的实时相互作用仍未完全了解。在本研究中，我们基于表面等离子体共振（SPR）实时监测了三种裂解酶（ClyF、ClyC、PlySs2）与芯片上培养的生物膜之间的相互作用。典型的SPR响应曲线表明，裂解酶迅速与生物膜结合，生物膜破坏在较长时间后开始。通过使用1:1结合模型分析，发现ClyF、ClyC和PlySs2的亲和常数（ ）分别为3.18±0.127μM、1.12±0.026μM和15.5±0.514μM。ClyF和PlySs2共享相同的CBD但对生物膜表现出不同亲和力这一事实表明，不仅CBD，而且CD也会影响整个裂解酶的结合活性。SPR平台可用于增进我们对裂解酶与细菌生物膜之间复杂相互作用的理解，包括缔合（吸附）和解离（破坏）。
