In most of us, the complex ecosystem of microbes that inhabit the gastrointestinal tract includes fungi. Most of these are in the genus Candida, with Candida albicans as the most prominent species. While some inroads have been made into the role of the bacterial microbiota and how dysbiosis affects human health, the biology of fungi in the gut is poorly understood. In immunocompromised patients, Candida is also a common and frequently lethal pathogen, and we have limited tools available to treat these infections. Given that the gut population of Candida is thought to be the source of these systemic infections, a better understanding of how C. albicans interacts with the host and with the bacterial microbiota is imperative.
We know that there is substantial genetic and phenotypic variation in isolates of C. albicans from different people. In experimental model systems, this results in a difference in disease severity, and it is reasonable to assume that some individuals harbor aggressive C. albicans strains while others have less virulent isolates. Yet most strains of C. albicans are collected from active infections, not from the normal commensal flora.
This project will use C. albicans strains isolated from the gastrointestinal tract of ICU patients who do not have active infections to assess the variation both across the population and within single individuals. Our goal is to determine whether there are phenotypic and/or genotypic markers that correlate with the propensity to disseminate from the gut and cause infections. This could have important implications in targeting antifungal prophylaxis in at-risk patients. We will also perform a pan-genome analysis, which has not been reported in C. albicans, to catalog the complete genomic repertoire of this species.
Team Fungi
Mike Lorenz, Ph.D. (UT-McGovern Medical School); Project PI
Candida host-pathogen interactions, fungal genetics
Christian Perez, Ph.D. (UT-McGovern Medical School); Project co-PI
Candida gut biology/host pathogen interactions
Max Adelman, M.D. (Houston Methodist Research Institute)
ID Fellow, access to patient-derived samples
Rodrigo de Paula Baptista, Ph.D. (HMRI)
Bioinformatics of eukaryotic pathogens