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Transmission, Ecology, and Evolution of Bacterial Pathogens

A key effort in the Food Safety Lab is to develop a better understanding of the transmission, ecology, and evolution of bacterial pathogens and to translate this knowledge into improved detection methods and control strategies. Current research focuses on both transmission, ecology, and evolution of Listeria monocytogenes and Salmonella, including major efforts on the use of full genome sequencing to understand the evolution of Salmonella and Listeria, including the evolution of clonal groups that show host specificity or distinct virulence characteristics. Projects on the ecology of foodborne pathogens focus on (i) understanding transmission and ecology of Listeria monocytogenes and Salmonella in produce production (pre-harvest) environments; (ii) transmission of Salmonella in dairy farms; and (iii) transmission of Listeria monocytogenes in processing facilities.

Relevant Key Publications:

  1. Soyer, Y., A. Moreno Switt, M.A. Davis, J. Maurer, P.L. McDonough, D. J. Schoonmaker-Bopp, N. B. Dumas, T. Root, L.D. Warnick, Y.T. Grohn, and M. Wiedmann. 2009. Salmonella 4,5,12:i:-: an emerging Salmonella serotype that represents multiple distinct clones. J. Clin. Microbiol. 47: 3546–3556.
  2. Soyer, Y., R. Orsi, L. Rodriguez Rivera, Q. Sun, and M. Wiedmann. 2009.  Genome wide evolutionary analyses reveal serotype specific patterns of positive selection in selected Salmonella serotypes. BMC Evol. Biol 9 (1):264.
  3. Cummings, K. J., L. D. Warnick, M. Elton, L.D. Rodriguez–Rivera, J.D. Siler, E.M. Wright, Y.T. Gröhn, and M. Wiedmann. 2010.  Salmonella enterica serotype Cerro among dairy cattle in New York: an emerging pathogen? Foodb. Path. Dis. 7:659-665.
  4. Den Bakker, H. C., B. N. Bundrant, E. D. Fortes, R. H. Orsi, and M. Wiedmann. 2010. A population and phylogenetic approach to understand the evolution of virulence in the genus Listeria. Appl. Environ. Micro. 76:6085-6100.
  5. Orsi, R. H., H. C. den Bakker, and M. Wiedmann. 2011. Listeria monocytogenes lineages: genomics, evolution, ecology and phenotypic characteristics. International Journal of Medical Microbiology 301: 79–96.
  6. den Bakker, H. C., C. A. Cummings, V. Ferreira, P. Vatta, R. H. Orsi, L. Degoricija, M. Barker, O. Petrauskene, M. R. Furtado, and M. Wiedmann. 2010. Comparative genomics of the bacterial genus Listeria: Genome evolution is characterized by limited gene acquisition and limited gene loss. BMC Genomics 2010 Dec 2;11:688.
  7. Hoelzer, K., B. D. Sauders, M. D. Sanchez, P. T. Olsen, M. M. Pickett, K. J. Mangione, D. H. Rice, J. Corby, S. Stich, E. D. Fortes, S. E. Roof, Y. T. Grohn, M. Wiedmann, and H. F. Oliver. 2011. Prevalence, distribution, and diversity of Listeria monocytogenes in retail environments, focusing on small establishments and establishments with a history of failed inspections.  J. Food Prot. 74: 1083-1095.
  8. Den Bakker, H.C., AI Moreno Switt, G Govoni, CA Cummings, ML Ranieri, L Degoricija, K Hoelzer, L.D. Rodriguez-Rivera, S. Brown, E. Bolchacova, M.R. Furtado and M. Wiedmann. 2011. Genome sequencing reveals diversification of virulence factor content and possible host adaptation in distinct subpopulations of Salmonella enterica. BMC Genomics 12(1):425.
  9. den Bakker, H. A. Moreno Switt, C. Cummings, K. Hoelzer, L. Degoricija, L. Rodriguez-Rivera, E. Wright, R. Fang, M. Davis, T. Root, D. Schoonmaker-Bopp, K. Musser, E. Villamil, H. Waechter, L. Kornstein, M. Furtado, and M. Wiedmann. 2011. A whole genome SNP based approach to trace and identify outbreaks linked to a common Salmonella enterica subsp. enterica serovar Montevideo Pulsed Field Gel Electrophoresis type. Appl. Environ. Micro. 77:8648-55.
  10. Moreno Switt, A. I., H. C. den Bakker, C. A. Cummings, L. D. Rodriguez-Rivera, G. Govoni, M. L Ranieri, L. Degoricija, S. Brown; K. Hoelzer; J. E. Peters, E. Bolchacova; Manohar R Furtado; and M. Wiedmann.  2012. Identification and Characterization of Novel Salmonella Mobile Elements Involved in the Dissemination of Pathogenic Genes. PLoS ONE 7(7): e41247. doi:10.1371/journal.pone.0041247.
  11. Strawn, L. K., E. D. Fortes, E. A. Bihn, K. K. Nightingale, Y. T. Gröhn, R. W. Worobo, M. Wiedmann, and P. W. Bergholz. 2013. Landscape and meteorological factors affecting prevalence of three foodborne pathogens in fruit and vegetable farms. Appl. Environ. Micro. 79:588-600.
  12. den Bakker, H., C. Desjardins, A. Griggs, J. Peters, Q. Zeng, S. Young, C. Kodira, C. Yandava, T. Hepburn, B. Haas, B. Birren, and M. Wiedmann. 2013. Evolutionary Dynamics of the Accessory Genome of Listeria monocytogenes. PLoS ONE 8(6): e67511. doi:10.1371/journal.pone.0067511.
  13. Strawn, L. K., Y. T. Gröhn, S. Warchocki, R. W. Worobo, E. A. Bihn, and M. Wiedmann. 2013. Risk Factors Associated with Salmonella and Listeria monocytogenes Contamination of Produce Fields. Appl. Environ. Micro. 79:7618-7627.
  14. Orsi, R. H. and M. Wiedmann. 2016. Characteristics and distribution of Listeria spp., including Listeria species newly described since 2009. Appl. Micro & Biotech. doi:10.1007/s00253-016-7552-2.