XIANG YANG ZHU

Graduate Student

Xiang Yang Zhu

THESIS RESEARCH PROJECT:

My project is to study the signal transduction in bacterial chemotaxis. Like many other systems, a two-component regulatory system plays a key role in allowing bacteria to respond to environmental changes. CheA, the sensor component, receives signals from chemoreceptors, and then transfers the signal to CheY, the response regulator, by protein phosphorylation. CheY-P interacts with the motor switch complex and causes cell changing swimming pattern. CheY is one of the few response regulators for which a detailed three dimensional structure is known. To understand the signal flow in CheY molecule, point mutations caused CheY functional defects are made by site-directed mutagenesis. The phenotypes of the mutants are characterized by both traditional swarm assay and computer motion analysis programs with Motion Analysis Corporation CellTrak software. To find out which step where the CheY mutants affect on, the ability of phosphorylation and dephosphorylation of the mutant proteins are compared with that of the wild-type CheY, and so does their binding ability to the switch proteins. On the other hand, the three dimensional structures of several mutant proteins are solved by using crystallographic approaches. The mutant structure are compared with that of the wild-type CheY to see the structural movements caused by mutations.

Curriculum vita -- Select this option to see Mr. Zhu's curriculum vita.

Publication list -- Select this option to see Mr. Zhu's publication list.

Return to Matsumura Lab Homepage