Professional and Biographical Information


Postdoctoral fellowship, Division of Infectious Diseases, Children’s Hospital Boston, Harvard Medical School (2008 – 2012)

Ph.D., Scripps Institution of Oceanography, University of California, San Diego, Marine Biology (2007)

B.S., College of William and Mary, Biology and Chemistry (2000)

Research Interests

For more information about our lab, please take a look at our laboratory website!

Many bacterial species use carefully regulated attachment and virulence mechanisms to colonize and sometimes sicken their eukaryotic hosts.  My laboratory aims to understand the complex molecular ‘conversations’ that underlie these interactions by studying Vibrio cholerae, the Gram-negative bacterium that causes cholera, an acute diarrheal disease that affects hundreds of thousands of people each year. 

Vibrio cholerae is naturally found in aquatic environments, often attached to phytoplankton, aquatic arthropods such as copepods, and larger organisms.  V. cholerae also can be carried by terrestrial arthropods such as houseflies.  Our laboratory explores interactions between V. cholerae and arthropods using Drosophila melanogaster, the common fruit fly, as a model system.  In the course of our work, we have discovered specific V. cholerae genes that are required for virulence and colonization in Drosophila.  These include genes that likely initiate signal transduction cascades that regulate expression of V. cholerae genes in the fly.  Our lab is interested in understanding how these regulatory cascades work; that is, what genes do they regulate?  What environmental signals do they sense?  How are they turned on and off? 

Ultimately, this project will reveal the genetic mechanisms that allow V. cholerae to associate with arthropods in order to survive and spread in the rivers, lakes, ponds, and oceans that let the disease persist in areas where it is endemic, and spread to distant locales.  Our ultimate goal is to better understand the ecology and evolution of a pathogen of major public health importance by integrating genomic, genetic, molecular and environmental approaches.

Teaching Interests

At Amherst, I teach Biol-271 Microbiology, a course that invites students to explore the world from a microbial point of view.  We seek to understand the diversity of ways in which microbes acquire energy, skirt immune responses, cause disease, rapidly adapt to change, and colonize almost every imaginable niche on the planet.  In the laboratory, we use classical and molecular microbiological techniques to explore this remarkable microbial diversity, and in the classroom we incorporate readings from the primary literature that highlight the most exciting recent findings in many areas of microbiology, including microbial genetics, genomics, pathogenesis, cell structure, ecology and diversity. 

I am also excited to be teaching a class for non-majors, Biol-110 Contagion, that focuses on mechanisms of bacterial and viral infectious disease and disease transmission.  We discuss the molecular biology of pathogenesis, but we also explore larger societal issues related to the burden of infectious disease today. 

I have also taught a specialized seminar course, Biol-414 Seminar in Microbiology: Host-Microbe Interactions and I have co-taught Biol-191 Molecules, Genes and Cells.  

My hope is that my students leave my classes with a deep appreciation and understanding for the critical roles that these unseen bacteria, archaea, and viruses play throughout their own lives, the lives of their fellow humans, and the health of the planet.

Selected Publications (* indicates Amherst College undergraduate co-authors)

Muzhingi* I, C Prado, M Sylla*, FF Diehl*, DK Nguyen*, MM Servos*, S Flores Ramos* and AE Purdy. 2018. Modulation of CrbS-dependent activation of the acetate switch in Vibrio cholerae.  Journal of Bacteriology. In press.

Liimatta* K, E Flaherty*, G Ro*, DK Nguyen*, C Prado, and AE Purdy. 2018. A putative acetylation system in Vibrio cholerae modulates virulence in arthropod hosts. Applied and Environmental Microbiology. In press.

Purdy AE. 2018. “Fly models of Vibrio cholerae infection and colonization. Methods in Molecular Biology, special edition on Vibrio cholerae. Edited by Aleksandra Sikora. Humana Press: New York, NY.

Kamareddine L, ACN Wong, AS Vanhove, S Hang, AE Purdy, K Kierek-Pearson, JM Asara, A Ali, JG Morris Jr., and PI Watnick.  2018. Activation of Vibrio cholerae quorum sensing promotes survival of an arthropod host.  Nature Microbiology. 3:243-252.

Jacob K, A Rasmussen*, P Tyler*, MM Servos*, M Sylla*, C Prado, E Daniele, J Sharp, and AE Purdy.  2017. A conserved two component signal transduction system controls expression of acetyl-CoA synthase in diverse Pseudomonas and Vibrio cholerae strains. PLOS ONE May, 2017.

El-Bassoiuny G, V Luizzi*, D Nguyen*, JG Stoffolano Jr. and AE Purdy. 2016. Vibrio cholerae laboratory infection of adult house fly Musca domestica. Med Vet Entomol. 30:392-402.

Hang S, AE Purdy, Z Wang, S Chang, WP Robins, JJ Mekalanos and PI Watnick. 2014. A bacterial acetate switch directs host metabolism from within the intestinal lumen. Cell Host & Microbe 16:592-604.     **Highlighted in Nature Reviews Microbiology January 2015.

Wang Z, S Hang, AE Purdy and PI Watnick. 2013. Mutations in the IMD pathway and Mustard counter Vibrio cholerae suppression of intestinal stem cell division in DrosophilamBio. 4(3) e00337-13.

Purdy AE and PI Watnick. 2011. Spatially-selective colonization of the arthropod intestine through activation of Vibrio cholerae biofilm formation. Proc Natl Acad Sci USA 108:19737-19742.

Purdy AE, D Balch, ML Lizarraga-Partida, MS Islam, J Martinez-Urtaza, A Huq, RR Colwell and DH Bartlett.  2010. Diversity and distribution of cholix toxin, a novel ADP-ribosylating factor from Vibrio cholerae. Environ Microbiol Rep. 2(1):198–207.

Jorgensen* R, AE Purdy*, R Fieldhouse, M Kimber, DH Bartlett and AR Merrill. 2008. Cholix toxin, a novel ADP-ribosylating factor from Vibrio cholerae. J Biol Chem 283:10671-10678.  *These authors contributed equally.

Makri S, AE Purdy, D Bartlett and J Fierer. 2007. Pathogenicity of environmental isolates of V. cholerae in mice. Microb Infect  9:1351-1358.

Purdy A, F Rohwer, R Edwards, F Azam and DH Bartlett. 2005. A glimpse into the genome content of the Vibrio cholerae species through identification of genes present in environmental strains.  J Bacteriol 187:2992-3001.

Awards and Honors

NIH Ruth L. Kirschstein NRSA Individual Fellowship (2009 - 2011)

Peterson Fellowship, Scripps Institution of Oceanography (2007)

Howard Hughes Medical Institute Predoctoral Fellowship (2001 - 2006)

Claude ZoBell Fellowship, Scripps Institution of Oceanography (2001)   

Highest Honors in Biology, William & Mary (2000)

Charlotte P. Mangum Prize in Biology, William & Mary (2000)   

Phi Beta Kappa, William & Mary (1999)


Scholarly and Professional Activities

American Society for Microbiology, member

Association for Women in Science, member