Gram-negative bacteria; Bordetella; Enteric bacteria; Vibrio cholerae; Gene regulation; Adjuvants; Mucosal immunology; Vaccines
Research in the Connell lab is focused in two areas: (1) microbial pathogenesis and (2) mucosal immunology. In the field of microbial pathogenesis, we are employing recombinant biology, physiology, and biochemistry to evaluate the methods by which Bordetella pertussis and B. bronchiseptica, respiratory pathogens of humans and other animals, acquire nutrient iron and heme from the fluids, cells, and tissues of the host during infection. We have identified several iron uptake systems. Expression of these systems is tightly controlled by three-component regulatory systems that respond to extracellular sources of iron. We have also investigated protein secretion in the enteric pathogen Vibrio cholerae. Our immunological research focuses upon evaluating the molecular, cellular, and organismal mechanisms by which two novel bacterial enterotoxins potentiate mucosal and systemic immune responses to foreign antigens. These later studies to investigate the adjuvant activities of those enterotoxins have direct implications in vaccine development.