Lettuce immune response and metabolite modulation against human pathogenic bacteria.

This study investigates the transcriptional and metabolic responses of different lettuce (Lactuca sativa) genotypes upon exposure to the human pathogens Salmonella enterica serovar Typhimurium 14028s and Escherichia coli O157:H7. Leafy greens, including lettuce, are frequently associated with foodborne outbreaks caused by these bacteria, yet the molecular interactions between the plant host and human pathogens remain poorly understood. The study integrates transcriptomic and metabolomic data to uncover key metabolic pathways and molecular mechanisms that may influence pathogen survival in the apoplast. The primary objectives of this project are to (i) characterize genotype-specific transcriptional responses of lettuce upon bacterial colonization, (ii) assess whether these responses align with changes in apoplastic metabolite composition, and (iii) determine potential defense-related mechanisms or susceptibility factors that could impact pathogen persistence. Understanding how different lettuce genotypes respond at the molecular level to human pathogens is essential for identifying plant traits that may either restrict or facilitate pathogen colonization. These findings contribute to broader efforts in food safety, particularly in breeding or production strategies aimed at reducing microbial contamination of fresh produce.