Basil essential oil induces multifactorial stress in Klebsiella variicola : A potential natural strategy to control a foodborne pathogen
Valentina Pavone, Ivanka Krasteva, Maria Schirone, Clemencia Chaves López, Francisco Emilio Agote Vega, Lisa Di Marcantonio, Nicola D’Alterio, Flavio Sacchini, Antonello Paparella, Mirella LucianiAbstract
Aims
Klebsiella variicola, traditionally considered a plant-associated bacterium, is emerging as a foodborne and opportunistic pathogen with growing antimicrobial resistance. Its persistence in food and food-processing environments represent a potential risk to public health. This study aimed to investigate how basil (Ocimum basilicum) essential oil (BEO), a plant-derived antimicrobial, affects the physiology of K. variicola and to identify molecular targets that could reduce its persistence in food-related environments.
Methods and Results
We applied a label-free quantitative proteomic approach to examine the global responses of K. variicola to a subinhibitory concentration of BEO. Exposure to BEO induced multifactorial stress responses, including altered membrane homeostasis, oxidative management, and translation processes. Key energy-related pathways were downregulated while antioxidant defenses were upregulated, indicating that BEO imposes combined physiological stresses rather than acting through a single mechanism.
Conclusions
These findings provide the first proteome-level insight into the cellular response of K. variicola to EO and highlight molecular vulnerabilities that could be exploited to limit its survival in food-processing settings. Overall, the study supports the potential of BEO as a natural antimicrobial strategy to improve food safety.