Characterization of Coxiella burnetii Effector CBU0041's Role in Host Cell Modulation

Abstract

A yeast suppressor screen was employed to identify proteins synthesized by Saccharomyces cerevisiae, which suppress the toxicity of C. burnetii effector CBU0041 (CirA). Transformants were serially diluted and spotted onto dropout media to verify suppression, and plasmids isolated from suppressed yeast were sequenced. Sequencing identified Rho1 as a suppressor of CirA. To determine if other Rho GTPases can suppress toxicity, all six small Rho GTPases were individually overexpressed in the CirA expressing yeast. Using this approach we found that Cdc42, Rho1, Rho2, and Rho4 suppress CirA toxicity and represent the probable targets of this protein.