Robert A. Cramer Jr., Ph.D. -Principal Investigator
Robert A. Cramer Jr., Ph.D. -Principal Investigator
Assistant Professor Fungal Pathogenesis
MSU Campus
My interest in fungal pathogenesis began as a Masters graduate student at Colorado State University in Fort Collins, Colorado, studying the Fusarium Wilt pathogen of common bean, Fusarium oxysporum f.sp. phaseoli. During my MS studies, we characterized the F. oxysporum population in the Central High Plains (Colorado, Wyoming, Nebraska) that infect common bean and sugarbeets. My studies led me to question the underlying genetic differences between non-pathogenic and pathogenic fungi. I pursued my interests in the molecular genetics of fungal pathogenesis for my Ph.D. in the laboratory of Dr. Christopher Lawrence. During my Ph.D. studies, we developed molecular and functional genomic tools for the study of the necrotrophic Brassica pathogen Alternaria brassicicola and identified potential virulence factors.
After completion of my dissertation, I began studies on the human fungal pathogen Aspergillus fumigatus, at Duke University Medical Center with Dr. John Perfect and Dr. William Steinbach. Currently, we are interested in how this normally benign fungus is capable of causing disease in immunocompromised patients. We are focusing our efforts on elucidating the molecular mechanisms of fungal growth in the mammalian lung and how this influences innate immune responses. We are particularly interested in the role of hypoxia, both from the perspective of the fungus and the host. A major portion of our current research is examining the role of the fungal sterol-regulatory element binding protein, SrbA, in hypoxia adaptation, drug resistance, and fungal virulence. In addition, we are interested in how the master regulator of the mammalian hypoxia response, HIF1, influences macrophage and neutrophil responses to A. fumigatus. Thus, our long term goal is to better understand the mechanisms of hypoxia responses in both the pathogen and host in order to develop new therapeutic options to improve invasive aspergillosis patient outcomes.
About Me
In vivo image of hypoxic lesion surrounding airway in murine model of invasive pulmonary aspergillosis, 3 days after infection with Aspergillus fumigatus. This data illustrates the importance of hypoxia in A. fumigatus pathogenesis.
A. fumigatus orlA (Tps2) mutant showing severe morphological defects with calcofluor white stain. This mutant is avirulent in murine models suggesting an important role for Trehalose-6-Phosphate in A. fumigatus virulence.