Inactivation of Cronobacter sakazakii by blue light illumination and the resulting oxidative damage to fatty acids.
Can J Microbiol
; 65(12): 922-929, 2019 Dec.
Article
en En
| MEDLINE
| ID: mdl-31525298
ABSTRACT
Blue light (BL) exerts an antimicrobial effect on pathogenic bacteria. It has been hypothesized that its bactericidal activity depends upon the generation of reactive oxygen species (such as anion superoxides) and the resultant cellular damage. However, some aspects of this hypothesis needed to be tested and investigated. Thus, the work conducted herein examined the molecular impact of BL treatment on Cronobacter sakazakii, an emerging foodborne pathogen. The results showed that BL exhibited an efficient bactericidal effect against C. sakazakii. Under a sublethal BL dose, both intracellular anion superoxides and malondialdehyde (a marker of oxidative stress) contents were increased gradually. Moreover, permeability of the outer membrane was increased by approximately 50%, indicating membrane damage. Further investigation revealed alterations to cellular fatty acid profiles, with a decrease and disappearance of unsaturated fatty acids, including C182, C161, and C181. These data indicate that bacterial lipids, especially unsaturated fatty acids, are important molecular targets of BL photo-oxidation. The transcriptional response of bacteria to BL was also studied, and it was found that three genes were upregulated, including genes encoding antioxidants. The current study contributes towards an improved understanding of the bactericidal mechanisms of BL and highlights the importance of lipid and membrane damage.
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Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Estrés Oxidativo
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Cronobacter sakazakii
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Ácidos Grasos
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Luz
Idioma:
En
Revista:
Can J Microbiol
Año:
2019
Tipo del documento:
Article