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UW-Madison Food Research Institute
Pictures of JB Jeri Barak

Core Executive Committee, Food Research Institute
Associate Professor, Dept. Plant Pathology, College of Agricultural and Life Sciences, UW-Madison
Faculty: Food Pathogens and Toxins Cluster

790 Russell Laboratories
1630 Linden Drive
(608) 890-2581

Research Interests
Bacterial colonization of plants with a focus on food safety of fresh produce
Department Webpage
  • BS 1993, San Jose State University, San Jose, CA; Major: Marine Biology, English, Minor: Chemistry
  • PhD 2000, University of California-Davis, Davis, CA; Department of Plant Pathology
Research Focus

The evidence that plants are a common host of human enteric pathogens, such as Salmonella enterica and Shiga-toxin producing Escherichia coli is now overwhelming. There is strong scientific consensus that these human pathogens are also plant-associated microbes. Our lab focuses on advancing the field of plant-microbe interactions by studying the biology of S. enterica in association with plants. We are interested in the mechanisms required for S. enterica plant colonization. We take a diverse approach from bacterial genetics to computational biology. Our goal is to develop cutting edge studies focusing on S. enterica while spring boarding off the wealth of scientific knowledge available for its famous cousin, E. coli. Reducing food-borne illness caused by consumption of contaminated healthy food stuff such as fresh produce is an immediate need. However, the study of human enteric bacterial pathogens in association with plants is a young sub-discipline that requires investigation of basic biology to move toward the ultimate goal of reducing human illness.

Current Research Projects
  • Plant colonization mechanisms of Salmonella enterica and Shiga-toxin producing E. coli.
  • Plant and human pathogen interactions
  • Tri-trophic interactions: enteric bacterial pathogen - phytophagous insects - plants.
  • Niche adaptation and evolution of cross-domain bacteria.
Program Affiliations
  • University of Wisconsin Faculty: Food Pathogens and Toxins Cluster
  • American Phytopathological Society; member of the Public Policy Board
  • American Society for Microbiology (Professional Member)
  • University of Wisconsin–Madison Expert for News Media (human bacterial pathogens in association with plants, Salmonella enterica lifestyle outside a warm-blooded host)
Outreach / Selected Recent Presentations
  • Webinar: “Preharvest food safety practices for tomato” Plant Management Network. 2012
  • “Hanging on and hanging out, Salmonella's life in roots and leaves.” Symposium/platform talk: Interactions between plants and human pathogens, American Phytopathological Society Annual Meeting, Austin, TX. 2013.
  • “Fresh produce, the most likely source of salmonellosis; how Salmonella enterica uses plants as vectors to animal hosts.” Symposium/platform talk: Detection and control of foodborne pathogens, Food Research Institute Annual Meeting, University of Wisconsin-Madison, Madison, WI. 2013.
  • “Food-borne illness and its risk factors associated with fresh tomato production.” 4th International Symposium on Tomato Diseases and the 28th U.S. Annual Tomato Disease Workshop, Orlando, FL. 2013.
  • “The role of fresh produce in the life cycle of Salmonella and other food-borne illness bacterial pathogens.” Symposium/platform talk: Salmonella and friends, Food Research Institute Annual Meeting, University of Wisconsin-Madison, Madison, WI. 2012.
  • “Plant Pathology: a key discipline for food safety of fresh produce.” Keynote Address: Korean Plant Pathology Society Annual Meeting, Seoul, Korea. 2012.
  • “Salmonella's life in the roots.” 26th Annual Kenneth B. Raper Symposium on Microbiological Research, University of Wisconsin-Madison, Madison, WI. 2012.
  • “Hunting the plant essential Salmonella enterica genes.” Symposium/platform talk: Omics approaches for the characterization of interactions between human enteric pathogens and plants: a plant pathologists perspective, American Phytopathological Society Annual Meeting, Honolulu, HI. 2011.
  • “Genes, genomes, and microbial buddies: the biology of Salmonella enterica on plants.” Symposium/platform talk: International AgriFood Safety Symposium, Seoul, Korea. 2010.
  • “Plant pathology research and human pathogen in/on plants.” Symposium/platform talk: Human pathogens associated with edible plants. International Association Food Protection Annual Meeting, Anaheim, CA. 2010.
  • “Human pathogens on plants: issues for plant pathologists.” Symposium/platform talk: Assuring the safety of fresh produce: issues and strategies. American Phytopathological Society Annual Meeting, Charlotte, NC. 2010.
  • “The biology of Salmonella enterica on plants.” Food and Drug Administration, Center for Food Safety and Applied Nutrition, College Park, MD. 2010.


recent publication Soto-Arias JP, Groves RL, Barak JD. 2014. Transmission and Retention of Salmonella enterica by Phytophagous Hemipteran Insects. Appl. Environ. Microbiol. 80(17):5447-56
Soto-Arias JP, Groves R, Barak JD. 2013. Interaction of phytophagous insects with Salmonella enterica on plants and enhanced persistence of the pathogen with Macrosteles quadrilineatus infestation or Frankliniella occidentalis feeding. PLoS ONE 8(10):e79404 (PMC3812026)
Kwan G, Charkowski AO, Barak JD. 2013. Salmonella enterica suppresses Pectobacterium carotovorum subsp. carotovorum population and soft rot progression by acidifying the microaerophilic environment. MBio 4(1):e00557-12 (PMC3573663)
Barak JD, Schroeder BK. 2012. Interrelationships of food safety and plant pathology: the life cycle of human pathogens on plants. Annu Rev Phytopathol 50:241-66
Hao LY, Willis DK, Andrews-Polymenis H, McClelland M, Barak JD. 2012. Requirement of siderophore biosynthesis for plant colonization by Salmonella enterica. Appl. Environ. Microbiol. 78(13):4561-70 PMC3370490
Jahn CE, Selimi DA, Barak JD, Charkowski AO. 2011. The Dickeya dadantii biofilm matrix consists of cellulose nanofibres, and is an emergent property dependent upon the type III secretion system and the cellulose synthesis operon. Microbiology (Reading, Engl.) 157(Pt 10):2733-44
Barak JD, Kramer LC, Hao LY. 2011. Colonization of tomato plants by Salmonella enterica is cultivar dependent, and type 1 trichomes are preferred colonization sites. Appl. Environ. Microbiol. 77(2):498-504 PMC3020540
Barak JD, Gorski L, Liang AS, Narm KE. 2009. Previously uncharacterized Salmonella enterica genes required for swarming play a role in seedling colonization. Microbiology (Reading, Engl.) 155(Pt 11):3701-9
Yap MN, Yang CH, Barak JD, Jahn CE, Charkowski AO. 2005. The Erwinia chrysanthemi type III secretion system is required for multicellular behavior. J. Bacteriol. 187(2):639-48 PMC543537
Yap MN, Barak JD, Charkowski AO. 2004. Genomic diversity of Erwinia carotovora subsp. carotovora and its correlation with virulence. Appl. Environ. Microbiol. 70(5):3013-23 PMC404413
Charkowski AO, Barak JD, Sarreal CZ, Mandrell RE. 2002. Differences in growth of Salmonella enterica and Escherichia coli O157:H7 on alfalfa sprouts. Appl. Environ. Microbiol. 68(6):3114-20 PMC123925