Science / Technology - Colloquium
Monday, February 2, 2009
4:00 PM-5:00 AM
Olin Hall
107
Microfluidic technology has presented us with the opportunities to precisely control the cellular microenvironments (both chemical and mechanical) and, in combination with live cell imaging, to reveal the cellular responses at the single cell levels. In this talk I will present applications of microfluidics to the studies of receptor-mediated cell responses using bacterial chemotaxis as a model system. Using a comprehensive set of linear chemical gradients we verify unambiguously that E.
coli sense chemical concentration on the logarithmic scale (this is similar to sensory systems of higher organisms where the logarithm of the signal strength simply compacts a wide range of signal into a manageable one). This result, when combined with a theoretical model of bacterial chemotactic behavior, makes it possible to understand macroscopic cellular behavior by modeling the underlying microscopic pathway kinetics. In the case of multiple chemical gradients I will show that E. coli make their decisions on which chemical they should pursue first depending upon the receptor number ratio. More interestingly we find that in natural environments E. coli are able to modify their chemical tastes by changing the number of receptors of a given kind. While this behavior is undoubtedly related to E. colis survival strategy the exact reasons for it and its mechanisms remain to be discovered.
Cost: FREE
Sponsored by: WPI Physics Department, Dr. Izabela Stroe
Suggested Audiences: College
E-mail:
izabela@wpi.edu
Phone: 508-831-5249
Last Modified: January 21, 2009 at 10:40 AM
Powered by the Social Web - Bringing people together through Events, Places, & Common Interests