Ann M. Stevens


Department of Biological Sciences, Virginia Tech, Blacksburg, VA  24060-0910

Office: 219 Life Science I (Mail Code 0910) Lab: 222 Life Science I
Office Phone: (540) 231-9378
Lab Phone: (540) 231-2342
Fax Number: (540) 231-4043


1992-1996 - Postdoctoral Research, Microbiology, University of Iowa, Iowa City, IA
1993 - Ph.D., Microbiology, University of Illinois, Urbana, IL
1989 - M.S., Microbiology, University of Illinois, Urbana, IL
1987 - B.S. with Distinction, Microbiology, Iowa State University,
Ames, IA

Interdepartmental Microbiology Graduate Program at Virginia Tech


1983-1987       Work Study Laboratory Technician, Dept. of Microbiology, Iowa State University
1985                Roswell Park Memorial Inst. Summer Research Participant, Buffalo, NY
1986, 1987      Summer Research Tech., Microbial Genetics Div. Pioneer HiBred, Johnston, IA
1987                Undergraduate Research Project, Microbiology, Iowa State University
1987-1992       Graduate Research/Teaching Assistant, Microbiology, University of Illinois
1992-1996       Postdoctoral Research, Microbiology, University of Iowa
1997-2004       Assistant Professor, Biology (now Biological Sciences), Virginia Tech
2004-               Associate Professor, Biological Sciences, Virginia Tech


1983-1987 Phi Beta Kappa, Phi Kappa Phi and Dean’s List, Iowa State University
1987-1991 NIH Predoctoral Trainee in Cell & Molecular Biology, Monsanto Fellowship, Excellent Instructor Ranking and DeBoer Fellowship, Univ. of Illinois
1994-1996 NIH Postdoctoral Trainee in Infectious Diseases, University of Iowa
1999-2004 NSF CAREER Award Recipient, Virginia Tech
2002, 2003, 2007 Dept. of Biology/Biological Sciences Teaching Award, Virginia Tech
2004, 2007 College of Science Certificate of Teaching Excellence, Virginia Tech
2005-2008 Recognized for teaching efforts by three VT student organizations
2009 Advisor of the Year, University Student Leadership Award, Student Activities
2009 VT Alumni Teaching Award, Member Academy of Teaching Excellence

Research Areas of Interest: The Stevens lab works in the general field of molecular microbiology with anemphasis on bacterial environmental sensing and gene regulation.  The majority of the research projects focus on the phenomenon of bacterial quorum sensing, a mechanism whereby bacterial cells communicatewith one another through the use of small molecules called autoinducers.  By understanding this mode of bacterial gene regulation, methods to manipulate it in ways beneficial to society may be discovered.  Our group currently studies the quorum sensing systems of three different bacteria.  Two are Vibrios, one that establishes symbiotic/beneficial relationships with animals (Vibrio fischeri) and another that is a human pathogen (Vibrio parahaemolyticus).  The third is an important plant/corn pathogen (Pantoea stewartii).

Courses Currently Teaching:

Publications over the past five years:

  1. Mastropaolo, M. D., N. P. Evans, M. K. Byrnes, A. M. Stevens, J. L. Robertson and S. B. Melville. 2005. Synergy in polymicrobial infections in a mouse model of type 2 diabetes. Infect. Immun. 73:6055-6063.

  2. Ruby, E. G., M. Urbanowski, J. Campbell, A. Dunn, M. Faini, R. P. Gunsalus, P. Lostroh, C. Lupp, J. McCann, D. Millikan, A. Schaefer, E. Stabb, A. Stevens, K. Visick, C. Whistler, and E. P. Greenberg. 2005. Complete genome sequence of Vibrio fischeri: A symbiotic bacterium with pathogenic congeners. Proc. Natl. Acad. Sci. USA 102:3004-3009.

  3. Groisman, A., C. Lobo, H. Cho, K. J. Campbell, Y. S. Dufour, A. M. Stevens and A. Levchenko. 2005. A microfluidic chemostat for experiments with bacterial and yeast cells. Nature Methods 2:685-689.

  4. Kulkarni, P. J., X. Cui*, J. W. Williams*, A. M. Stevens, R. V. Kulkarni. 2006. Prediction of CsrA-regulating small RNAs in bacteria and their experimental verification in Vibrio fischeri. Nucleic Acids Res. 34:3361-3369.

  5. Qin, N., S. M. Callahan, P. V. Dunlap and A. M. Stevens. 2007. Analysis of LuxR regulon gene expression during quorum sensing in Vibrio fischeri. J. Bacteriol. 189:4127-4134.

  6. Muller, J. F., A. M. Stevens, J. Craig and N. G. Love. 2007. Transcriptome analysis reveals that multidrug efflux genes are upregulated to protect Pseudomonas aeruginosa from pentachlorophenol stress. Appl. Environ. Microbiol. 73: 4550-4558.

  7. Antunes, L.C., A. L. Schaefer, R. B. Ferreira, N. Qin, A. M. Stevens, E. G. Ruby and E. P. Greenberg. 2007. Transcriptome analysis of the Vibrio fischeri LuxR-LuxI regulon. J. Bacteriol. 189: 8387-8391.

  8. Cho, H., H. Jonsson, K. Campbell, P. Melke, J. W. Williams, B. Jedynak, A. M. Stevens, A. Groisman and A. Levchenko. 2007. Self-organization in high-density bacterial colonies: Efficient crowd control. PLoS Biol. 5:e302.

  9. Walker, C. L., M. T McGill, A. L. Buikema, Jr. and Ann M. Stevens. 2008. Implementing inquiry-based learning in teaching serial dilutions. J. College Science Teaching. 37: 56-61.

  10. von Bodman, S. B., A. L. Carlier and A. M. Stevens.  2008. The role of quorum sensing regulation in the pathogenesis of Pantoea stewartii subsp. sterwartii.  In: Chemical Communication Among Microbes (S. W. Winans and B. A. Bassler, eds.), ASM Press Washington, DC.

  11. Williams*, J. W., X. Cui*, A. Levchenko and A. M. Stevens. 2008. Quantitative analysis reveals robust and sensitive control of a quorum sensing circuit by two interlocked feedback loops. Mol. Syst. Biol. 4:234. (10 pages)

  12. Learman, D. R., H. Yi, S. D. Brown, S. L. Martin, G. G. Geesey, A. M. Stevens, M. F. Hochella, Jr. 2009. Shewanella oneidensis MR-1 LuxS involvement in biofilm development and sulfur metabolism.  Appl. Environ. Microbiol. 75:1301-1307.

  13. Mastropaolo*, M. D., M. L. Thorson*, A. M. Stevens. 2009. Comparison of Bacteroides thetaiotaomicron and Escherichia coli 16S rRNA gene expression signals. Microbiology. 155:2683-2693.

  14. Schu*, D. J., A. L. Carlier, K. P. Jamison*, S. von Bodman, A. M. Stevens. 2009. Structure/function analysis of the Pantoea stewartii quorum-sensing regulator EsaR as an activator of transcription. J. Bacteriol. 191: 7402-7409.

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