The majority of chronic infections are caused by biofilms, which have higher levels of antibiotic resistance than planktonic growth. Violet-blue 405 nm light has recently emerged as a novel bactericide, but limited studies have been conducted on its effectiveness against biofilms. We found that in response to 405 nm light both Pseudomonas aeruginosa and Bacillus subtilis biofilms exhibited cell dispersal and membrane potential hyperpolarisations. The response to 405 nm light depended on the stage of biofilm growth. The use of reactive oxygen species scavengers reduced membrane hyperpolarisation and biofilm dispersal in response to 405 nm light. This is the first time that membrane potential hyperpolarisations have been linked with photooxidative stress in bacteria and with biofilm dispersal. These results provide a new insight into the role of membrane potentials in the bacterial stress response and could be used in the development of 405 nm light based biofilm treatments.

中文翻译：

---

膜电势，氧化应激和细菌生物膜对405 nm光的扩散响应。

大多数慢性感染是由生物膜引起的，生物膜比浮游生物具有更高的抗生素抗性水平。紫蓝色405 nm的光近来已成为一种新型杀菌剂，但有关其对生物膜的有效性的研究很少。我们发现响应于405 nm的光，铜绿假单胞菌和枯草芽孢杆菌生物膜均表现出细胞分散和膜电位超极化现象。对405 nm光的响应取决于生物膜生长的阶段。活性氧清除剂的使用减少了膜超极化和生物膜扩散，以响应405 nm光。这是膜电位超极化首次与细菌中的光氧化应激和生物膜扩散相关联。