Single-cell analysis reveals microbial spore responses to sodium hypochlorite
Weiming Yang1,2, Yufeng Yuan1, Lin He111School of Electrical Engineering and Intelligentization, Dongguan University of Technology, Dongguan, Guangdong, China2School of Information and Optoelectronic Science and Engineering, South China Normal University, Guangzhou, Guangdong, China *Correspondence Lin He, School of Electrical Engineering and Intelligentization, Dongguan University of Technology, Dongguan 523808, Guangdong, China E-mail: helin@dgut.edu.cnHaihua Fan, School of Information and Optoelectronic Science and Engineering, South China Normal University, Guangzhou 510006, Guangdong, China E-mail: fanhh@scnu.edu.cn,*, Haihua Fan2,*
Abstract: Pollution from toxic spores has caused us a lot of problems, because spores are extremely resistant and can survive most disinfectants. Therefore, the detection of spore response to disinfectant is of great significance for the development of effective decontamination strategies. In this work, we investigated the effect of 0.5% sodium hypochlorite on the molecular and morphological properties of single spores of Bacillus subtilis using single-cell techniques. Laser tweezers Raman spectroscopy showed that sodium hypochlorite resulted in Ca2+-dipicolinic acid release and nucleic acid denaturation. Atomic force microscopy showed that the surface of treated spores changed from rough to smooth, protein shells were degraded at 10 min, and the permeability barrier was destroyed at 15 min. The spore volume decreased gradually over time. Live-cell imaging showed that the germination and growth rates decreased with increasing treatment time. These results provide new insight into the response of spores to sodium hypochlorite.
Key words : atomic force microscopy; Bacillus subtilis ; laser tweezers Raman spectroscopy; morphological structure; single-cell analysis