Location: Produce Safety and Microbiology Research
Project Number: 2030-42000-050-024-I
Project Type: Interagency Reimbursable Agreement
Start Date: Aug 15, 2019
End Date: Sep 30, 2019
Objective:
To characterize the microbiome of lettuce leaves from field through processing and storage and its role in the colonization of lettuce by E. coli O157:H7.
Approach:
Leaves from lettuce of different lines with good and poor shelf life, grown as commercial and organic crops will be sampled in the field and during processing and storage in MAP. The resident phyllosphere microbiota will be recovered and analyzed for its community composition using genome sequencing and analysis. E. coli O157:H7 will be introduced (or not in control treatments) onto the leaves prior to packaging and the fate of the pathogen correlated with microbiome structure development during storage. Various genetic and chemical characteristics of the lettuce varieties that may play a role in determining the microbiome composition and the population size of E. coli O157:H7 will be determined also, such as carbohydrate profiles, and expression of basal plant defense genes in response to processing. The effect of storage temperature on the interaction of E. coli O157:H7 with varieties of different shelf life will be examined.
