Helene Andrews-Polymenis, D.V.M., Ph.D.
Assistant Professor
Department of Microbial and Molecular Pathogenesis
Laboratory Phone: 979-458-4041
Fax: 979-845-3479
E-mail: handrews@medicine.tamhsc.edu
Education
Ph.D. Tufts University School of Medicine, 1999
D.V.M. Texas A&M College of Veterinary Medicine, 2001
Research Interests
Genetic Basis of Intestinal Persistence of Salmonella enterica
Salmonella is a leading cause of food borne illness, causing an estimated 1.4 million cases per year in the United States. Serovar Typhimurium is responsible for about 26% of these cases (CDC, 1998). The vast majority of Salmonella infections in mammals and birds are the result of infection with S. enterica subspecies I serovars, yet very few genetic factors that are necessary for intestinal persistence in these reservoirs have been described. Intestinal persistence is critical for shedding and transmission of serovar Typhimurium in mammals and birds, yet this phenomenon and interaction of the organism with the host immune system during persistent infection is poorly understood. The long-term goal of our work is to understand the genetic basis of persistence and host range restriction of Salmonella enterica serovar Typhimurium in its mammalian hosts. We are currently working on the following projects:
1. Understanding the molecular role of STM0557 in intestinal persistence in murine models of infection.
We are investigating the role STM0557, a ssp. I specific gene, and surrounding genes STM0558 and 0559 in the ability of Typhimurium to persist in the intestine of Salmonella-resistant CBA/J mice. Nonpolar deletion mutants in STM0557, 0558 and 0559 are all defective for intestinal persistence in competitive infections with wild type ATCC14028 in Salmonella resistant CBA mice. All three of these genes are located on a recently described pathogenicity island termed SPI-16 (4, Vernikos & Parkhill 2006). STM0558 and 0559 resemble genes of the gtrA,B, V cluster in Shigella flexneri that are responsible for serotype conversion, by addition of a glucose to repeating O antigen subunits. In Salmonella these genes may be involved in ‘form variation’, of the O12 antigen by addition of a glucose to the O-4 position of the galactose of the O12 antigen. Extensive work on the 12-2 variation over 30 years ago by Makela and colleagues identified a 30 kB region, overlapping the STM0557-9 genes, as containing the genes responsible for generation of the 12-2 modification.
2. Functional Genomics of Salmonellae: Generation of a Complete Deletion Library
We are generating a library of targeted deletions using λ red recombination in all non-essential genes of Salmonella enterica serotype Typhimurium ATCC14028 in collaboration with Michael McClelland (Sidney Kimmel Cancer Center, San Diego CA). We currently have generated targeted deletions in 1032 genes specific to Salmonellae, or approximately ¼ of the genome, and are progressing to complete this collection. This library will be used for in vitro and in vivo screening, and will be an outstanding resource for the field!
3. In vitro Screening of Complete Deletion Library.
We are interested in the ability of Salmonellae to perisist in the mammalian and avian intestine, thus we are interested in identification of mutants defective in all aspects of the lifestyle of this important pathogen in the host. We are currently screening our library of deletions to identify mutants with interesting phenotypes in vitro including: motility (both reduced and enhanced), resistance to gastric contents, resistance to bile acids. We welcome collaborators on these projects!!
4. In vivo Screening of Complete Deletion Library.
We are currently screening our pooled library in various animals to identify new genes important for intestinal persistence in these models. Animal models we are using are Salmonella-resistant CBA/J mice and Chickens. We are actively pursuing collaborations for large animal livestock models as well, as livestock animals are the primary reservoir of Non-Typhoidal salmonellosis for humans and are thus an important food safety concern. We welcome collaborators on these projects!!
Laboratory Personnel:
Dr. Lydia Bogomolnaya - Postdoctoral Research Associate
Mollie Megan Reynolds - Ph.D. Candidate
HeeJeong Yang - Ph.D. Candidate
Dr. Christine Sivula - M.A. Candidate
Hans Verbocht - Intern, Research Assistant
Christine Shields- Undergraduate Research Assistant
Lindsay Aldrich - Undergraduate Research Assistant
Allegra Lamison - Undergraduate Research Assistant
Publications
Bogomolnaya, L., Santiviago, C. , Yang, H,J., Baumler, A.J., and H. Andrews-Polymenis (2008) Form Variation’ of the O12 Antigen is Critical for Persistence of Salmonella Typhimurium in the Murine Intestine. Submitted.
Lenz, L.L. and H. Andrews-Polymenis. (2008) Silencing the Alarm: insights into the interaction between host and pathogen. EMBO Reports 9, 27-32.
Andrews-Polymenis, H.L., Dorsey, C.,W., Raffatellu, M., and Bäumler. A.J. (2006) ‘Expression, function, and in vivo identification of Salmonella virulence factors.’ In Salmonella Infections: Clinical, Immunological and Molecular Aspects. Ed. Pietro Mastroeni (Cambridge University Press).
Andrews-Polymenis, H.L. and Baumler, A.J. ‘Salmonella ssp.’ In Pathogenomics. Ed. Joerg Hacker and Ulrich Dobrindt, (WILEY-VCH Verlag GmbH, Weinheim) 2005.
Tukel, C., Raffatellu, M., Humphries, A.D., Wilson, R.P., Andrews-Polymenis, H.L., Adams, L.G., and Baumler, A.J., (2005) Thin curled fimbriae are a pathogen-associated molecular pattern of Salmonella enterica serotype Typhimurium that is recognized by Toll-like receptor 2. Molecular Microbiology, 58(1), 289-304.
Raffatellu, M., Wilson, R.P., Tran, Q.T., Chessa, D., Andrews-Polymenis, H.L., Lawhon, S.D., Figueiredo, J.F., Adams, L.G., and Baumler, A.J. (2005) Host restriction of Salmonella enterica serotype Typhi is not caused by functional alteration of SipA, SopB or SopD. Infection and Immunity, 73(12), 7817-7826.
Raffatellu, M., Wilson, R.P., Chessa, D., Andrews-Polymenis, H.L., Tran, Q.T., Lawhon, S., Khare, S. Adams, L.G., and Bäumler, A.J. (2005) SipA, SopA, SopB, SopD, and SopE2 contribute to Salmonella enterica serotype Typhimurium invasion of epithelial cells. Infection and Immunity 73(1): 1-9.
Andrews-Polymenis, H.L., Rabsch, W., Porwollik, S., McClelland, M., Rosetti, C., Adams, L.G., and Bäumler, A.J.(2004) Host restriction of Salmonella enterica serotype Typhimurium pigeon isolates does not correlate with loss of discrete genes. Journal of Bacteriology 186(9): 2619-2628.
Zhang, S., Kingsley, R.A., Santos, R.L., Andrews-Polymenis, H., Raffatellu, M., Figueiredo, J., Nunes, J., Tsolis, R.M., Adams, L.G., and Bäumler, A.J. (2003) Molecular Pathogenesis of Salmonella enterica serotype Typhimurium-Induced Diarrhea. Infection and Immunity 71(1): 1-12.
Rabsch, W., Andrews, H.L., Kingsley, R.A., Prager, R., Tschaepe, H., Adams, L.G., and A. Bäumler, (2002) Salmonella enterica serotype Typhimurium and its host adapted variants. Infection and Immunity 70: 2249-2255.
Watarai, M.*, Andrews, H.L.*, and Isberg, R. R., (2001) Formation of a fibrous structure on the surface of Legionella pneumophila associated with exposure of DotH and DotO proteins after intracellular growth. Molecular Microbiology 39(2): 313-329. *The first two authors contributed equally to this work.
Vogel, J.P., Andrews, H.L., Wong, S.K., and Isberg, R.R. (1998) Conjugative transfer by the virulence system of Legionella pneumophila. Science 279: 873-876.
Andrews, H.L., Vogel, J.P., and Isberg, R.R. (1998) Identification of linked genes of Legionella pneumophila essential for intracellular growth and evasion of the endocytic pathway. Infection and Immunity 66(3): 950-958.
Kirby, J.E., Vogel, J.P., Andrews, H.L., and Isberg, R.R. (1998) Evidence for pore forming ability by L. pneumophila. Molecular Microbiology 27(2): 323-336.
Wang, J., Andrews, H., and Thukral, V., (1992) Presynaptic glutamate receptors regulate noradrenaline release from isolated nerve terminals. J. Neurochemistry 58(1): 204-211.
