Professor Janet Quinn, Institute for Cell and Molecular Biosciences, Newcastle University
Wednesday 4th March, 4.00 p.m., Stacey Lecture Theatre 1
Candida albicans is an important fungal pathogen of humans causing approximately 400,000 life-threatening systemic infections each year. Stress responses are essential for this fungal pathogen to evade host anti-microbial defence mechanisms and to survive rapidly changing microenvironments found within diverse host niches. We are particularly interested in the sensing and signalling mechanisms employed by C. albicans to perceive and respond to reactive oxygen species (ROS) encountered during infection. Upon contact with C. albicans, the NADPH oxidase complex in phagocytic cells produces high levels of superoxide which is rapidly converted to H2O2. To survive in the phagocyte C. albicans must mount a rapid transcriptional response to induce the expression genes encoding antioxidant and repair proteins. Furthermore, phagocytosis of C. albicans by macrophages, or exposure to ROS in vitro, initiates filamentous growth. In this talk I’ll highlight how oxidation of specific signalling proteins plays a key role in the perception and regulation of both transcriptional and morphogenetic responses to ROS in C. albicans. In addition, I’ll also describe some recent findings detailing mechanisms employed by the host to prevent the rapid oxidative stress responses needed for fungal survival.