Seasonal influenza is a common cause of lower respiratory tract infections that annually effect a large portion of the population. These infections typically range from mild to moderate in severity, however life-threatening cases can occur. Frequently, complications associated with influenza infections are due to secondary bacterial pneumonia predominately caused by Streptococcus pneumoniae or Staphylococcus aureus (Rynda-Apple, Robinson, & Alcorn, 2015). Many efforts to resolve this pathology have focused on the immunomoldulatory effects incurred during the primary influenza infection while little attention has been directed toward whether bacterial physiology and gene regulation change during influenza infection.
Approximately 30% of the population in developed countries are persistent asymptomatic carriers of S. aureus within the nares and an additional 16% are classified as intermittent carriers (Nouwen et al., 2004). Furthermore, advances in culture-independent techniques have dispelled the historic notion that the lung is a sterile environment and have provided evidence that organisms persisting in the upper …show more content…
aureus genome contains multiple 2-component signal transduction systems (TCS) that function to sense and respond to environmental signals by regulating gene expression(Nygaard et al., 2010). Previous work has established the importance of the SaeR/S TCS in S. aureus pathogenesis by demonstrating its role in regulating the transcription of virulence genes in response to various host stimuli; however, the environmental factors that trigger saeR/S and its impact on virulence in vivo remain incompletely defined (Nygaard et al., 2010; Zurek, Pallister, & Voyich, 2015). We hypothesis that S. aureus frequently encounters the lung environment but maintains an avirulent state by negatively regulating the saeR/S. Upon influenza infection, saeR/S is induced leading to up-regulation of virulence genes and resulting in secondary bacterial
Approximately 30% of the population in developed countries are persistent asymptomatic carriers of S. aureus within the nares and an additional 16% are classified as intermittent carriers (Nouwen et al., 2004). Furthermore, advances in culture-independent techniques have dispelled the historic notion that the lung is a sterile environment and have provided evidence that organisms persisting in the upper …show more content…
aureus genome contains multiple 2-component signal transduction systems (TCS) that function to sense and respond to environmental signals by regulating gene expression(Nygaard et al., 2010). Previous work has established the importance of the SaeR/S TCS in S. aureus pathogenesis by demonstrating its role in regulating the transcription of virulence genes in response to various host stimuli; however, the environmental factors that trigger saeR/S and its impact on virulence in vivo remain incompletely defined (Nygaard et al., 2010; Zurek, Pallister, & Voyich, 2015). We hypothesis that S. aureus frequently encounters the lung environment but maintains an avirulent state by negatively regulating the saeR/S. Upon influenza infection, saeR/S is induced leading to up-regulation of virulence genes and resulting in secondary bacterial