Biological Sciences Colloquium: Alyssa Kline

Alyssa Kline will present a talk about her work entitled, ‘Not All Adaptors Are Created Equal: Determining the Roles of the Dual Adaptors in the Pseudomonas aeruginosa Chp Chemosensory system’

The Abstract is as Follows:

The opportunistic pathogen, Pseudomonas aeruginosa, relies on the expression of type IV pili (T4P) for aspects of its virulence. T4P are long, flexible appendages used by bacteria in surface adhesion, biofilm maturation, and twitching motility. Expression of T4P-related genes and modulation of T4P activity in P. aeruginosa is dependent on the Chp chemosensory system. The core signaling complex of the Chp system consists of a single methyl-accepting chemotaxis protein (MCP; PilJ), two adaptor proteins (PilI, ChpC), and a histidine kinase (ChpA). These proteins organize themselves into large, highly ordered chemosensory arrays that are localized towards the poles. Classical models of chemosensory systems are based on the Escherichia coli Che system, which crucially contains only one adaptor protein. We investigated the roles of the two adaptors in Chp array composition and signal transduction using bacterial two-hybrid (BACTH) assays to identify interacting partners within the Chp system and fluorescence microscopy to investigate how the two adaptors impact protein localization and array formation. Using the results of these experiments, we constructed a model of Chp chemosensory arrays that describes the phenotypes seen in wild type, as well as pilI and chpC deletion mutants.

The presentation will begin at 4:00 PM in Lapham Hall N101, preceded by an informal reception from 3:45 – 4:00PM.