Department of Biology
413 Mugar Life Sciences
360 Huntington Avenue
Boston, MA 02115 USA
- Ph.D., California Institute of Technology
- B.A., Johns Hopkins University
- Director of Undergraduate Studies for Biology Department
- Faculty Director Center for Innovation and Excellence in Teaching and Learning
I study the sensory physiology of microorganisms—how bacteria and fungi respond to various chemical and physical signals in their environment. Although the basic mechanisms of this behavior have received considerable attention in recent years, little is known of its role in microbial ecology. Work in my laboratory has shown that motility and chemotaxis are used by Rhizobium meliloti during the infection of alfalfa roots, which eventually leads to symbiotic nitrogen fixation. We are refining our understanding of this phenomenon by using wild type and mutant cells labeled with green fluorescent protein to view the earliest steps in the infection process. New studies involve isolation of compounds from alfalfa root extracts, which attract rhizobia, analysis of the flagellar and the chemotaxis genes by various techniques (including transposon mutagenesis, transduction, gene cloning, and sequencing), and measurements of motility and chemotaxis in soil.
I am now the Director of Undergraduate Studies for Biology. In this role I have developed an NSF sponsored project to assess learning using student-created electronic portfolios.
I teach a course for teaching assistants that helps them to develop an active teaching style and supports their involvement in lab course curriculum improvement. My undergraduate teaching has recently been about student development (introduction to the department and the university for first year students and the capstone course for graduating students.