Dr. Anthony R. Flores
The University of Texas Health Science Center at Houston
McGovern Medical School
Department of Pediatrics
Streptococcus pyogenes (group A Streptococcus, GAS) is an obligate human pathogen that causes the relatively benign pharyngitis (“strep throat”) but also causes severe, life-threatening diseases such as toxic shock syndrome and necrotizing fasciitis (“flesh-eating disease”). Most commonly, however, GAS is carried in the throats of humans in the absence of signs or symptoms of disease. In fact, many bacterial pathogens including Streptococcus pneumoniae, Neisseria meningitidis, and Staphylococcus aureus exist primarily in a carrier state. Despite the commonality of this phenomenon, we understand little of the host-pathogen interaction that leads to a carrier state. Using GAS as a model organism, our goal is to identify key molecular mechanisms that contribute to GAS carriage and thus to pathogenesis. Key areas of interest in the Flores Laboratory include:
Molecular mechanisms that contribute to GAS asymptomatic carriage. A major focus is investigative studies toward understanding gene regulatory mechanisms that contribute to GAS carriage. We have identified mutations in genes critical to GAS gene regulation that are unique to GAS carrier strains. The laboratory seeks to understand the mechanism by which specific mutations alter gene regulation and how gene regulatory differences contribute to a unique GAS carrier phenotype characterized by increased ability to colonize mucosal surfaces and decreased ability to cause disease.
Streptococcal epidemiology and pathogenomics. A secondary focus of the laboratory uses bacterial whole genome sequencing to provide insights into pathogen outbreaks and epidemics. We have ongoing GAS disease surveillance programs investigating the phylogenetic differences among and between different sources of bacterial clinical isolates (e.g. carriage and disease-causing strains). Ultimately, these studies serve as the foundation for molecular studies performed in our laboratory.