Staphylococcus aureus (S. aureus) is an ubiquitous Gram-positive bacteria and a commensal organism of humans, colonizing the anterior nares of approximately 30% of the population. This versatile pathogen is responsible for a wide variety of disease, including skin infections, bacteremia, endocarditis, sepsis, and toxic shock syndrome. Recently, there has been a dramatic increase in the number of infections caused by methicillin-resistant S. aureus (MRSA) strains originating from outside healthcare settings. Community-associated MRSA (CA-MRSA) are a leading cause of skin and soft-tissue infections but can also cause a number of life-threatening invasive ailments including several not previously associated with S. aureus infection, such as necrotizing pneumonia and necrotizing fasciitis. The long-term objective of our research is to define the influence of sensory/regulatory systems on CA-MRSA virulence using clinically relevant strains. Relatively little is known about how pathogens detect components of the human innate immune system to respond and survive within the host. National Institutes of Health (NIH) funded projects in our laboratory investigate molecular mechanisms used by S. aureus to avert destruction by the human innate immune system at the host-pathogen interface during bacteremia and skin infections. Additional NIH funded projects include investigating the characteristics and incidence of MRSA nasal colonization in minority populations. Our lab is also funded by the United States Department of Agriculture (USDA). For our USDA projects we investigate incidence and characteristics of S. aureus in Montana’s dairy herds and study the antimicrobial potential of a chemokine found in bovine milk. We have also started to determine the zoonotic potential of S. aureus and are focusing on the incidence and transmission potential of S. aureus in Montana’s equine populations
