Our group is interested in how intracellular bacterial pathogens interact with and commandeer host cell functions during infection. We have studied the intracellular human pathogen, Legionella pneumophila for more than 30 years. This gram-negative species causes an acute febrile pneumonia called Legionnaires’ disease. People become infected with Legionella when they inhale contaminated aerosols. This can happen when cooling and ventilation systems, fountains, or whirlpools become contaminated. In these environments, Legionella replicates in single-celled amoebae. In human lungs these bacteria can infect and replicate in alveolar macrophages.
In order to understand how Legionella is able to survive and grow inside amoebae and macrophages, we use genetic and genomic approaches to ask which functions in the bacteria and which ones in the host are important for infection. We found that Legionella has a “Type IV Secretion System” called the Icm/Dot System that translocates protein “effectors” to the host cell and that these effectors dramatically alter organelle trafficking in host cells as is shown in the accompanying diagram. The Legionella – containing vacuole, (LCV) is where the bacteria grow within cells in a nutrient-rich, protected niche.
2010 - Professor of Microbiology, University of Chicago
1970-1974 University of Massachusetts, B.S. (Microbiology, honors)
1975-1980 Harvard University, Ph.D. (Biological Chemistry)
1980-1982 Postdoctoral Fellow, Department of Biochemistry & Molecular Biology, Harvard University
Employment / Experience:
1974-1975 Research Assistant, Institut Pasteur, Paris, France
1982-1989 Assistant Professor, Department of Microbiology, Columbia University
1989-1995 Associate Professor, Department of Microbiology, Columbia University
1995- 2010 Professor, Department of Microbiology, Columbia University
2005- 2008 Director of Graduate Studies, Department of Microbiology, Columbia University
2008 Interim Chair, Department of Microbiology, Columbia University
2010 Professor Emeritus, Department of Microbiology & Immunology, Columbia University
2010-2015 Director, Howard Taylor Ricketts Regional Biocontainment Laboratory
1986- 1997 Editorial Board, Journal of Bacteriology
1989- 1992 Editorial Board, Infection and Immunity
1994- 1999 Editorial Board, The Journal of Biological Chemistry
1998 Co-Chair, Gordon Research Conference: "Bacterial Cell Surfaces"
2007 Guest Editor, Proceedings of the National Academy of Sciences
2009 Editorial Board, Protist
2009 - 2010 Steering Committee, Northeast Biodefense Center
2009 - 2019 Editorial Board, mBio