Advancing the health and well-being of animals and people

Co-Principal Investigator: Craig Altier
Co-Principal Investigator: Gregory Martin

Contact Information: Email:; Phone: 607-253-3926
Sponsor: United States Department of Agriculture (USDA) Agriculture and Food Research Initiative (AFRI)
Grant Number: 2001-67017-30023
Title: Pathogen and Host Mechanisms Involved in Salmonella Infection of Tomato
Annual Direct Cost: $138,524
Project Period: 03/15/11-03/14/14

DESCRIPTION (provided by applicant): Infections with the food-borne bacterial pathogen Salmonella remain one of the most important threats to food safety in the US. Salmonella can be transmitted through a wide variety of foods, both plant and animal in origin, but is a major source of contamination of produce. A great deal is known about how Salmonella is able to survive in animal hosts, and thus contaminate meat, but very little is understood about the requirements of the pathogen to contaminate plants and vegetable products. Similarly, little is known about whether the plant immune system is an effective defense against Salmonella infection. This proposal will therefore seek to elucidate the means by which Salmonella survives and multiplies on plants and how plants defend themselves against attempted infection by Salmonella, specifically in the leaves and fruit of tomatoes. Our goals for this proposal are four: 1) Identify Salmonella genes that are selectively expressed when the pathogen lives on tomato plants; 2) Determine whether differentially expressed genes provide Salmonella with a selective advantage for growth on tomatoes; 3) Identify the means by which Salmonella induces genes essential for its colonization of tomatoes, and; 4) Investigate the role of PAMP-triggered immunity in suppressing Salmonella infection of tomato leaves and fruits. We anticipate that this work will identify potential intervention targets for preventing produce contamination. In parallel, it will characterize the molecular responses of tomato leaves and fruits to attempted Salmonella infection and will assess whether these responses play a role in inhibiting Salmonella growth in these tissues.