Article

Control of Virulence by Small RNAs in Streptococcus pneumoniae

Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America.
PLoS Pathogens (Impact Factor: 8.06). 07/2012; 8(7):e1002788. DOI: 10.1371/journal.ppat.1002788
Source: PubMed

ABSTRACT Author Summary
Pneumonia is a leading cause of childhood mortality worldwide, resulting in more deaths in young children than any other infectious disease. One of the leading causes of pneumonia is the human pathogen, Streptococcus pneumoniae, the causative agent of over six million infections each year in the United States. Understanding how bacterial pathogens rapidly respond to dynamic host environments is a central aspect of microbial pathogenesis. Accumulating evidence has implicated sRNAs as vital regulators in a number of important cellular processes though few have been implicated in virulence. In our investigations we have applied next-generation sequencing to define the sRNA repertoire of S. pneumoniae. In addition, we utilized both targeted genetic knockouts and transposon mutagenesis to show that a significant portion of these sRNAs play important roles at various stages of pneumococcal pathogenesis. These data represent the first example of sRNAs being involved in pneumococcal pathogenesis and greatly expand the number of sRNAs that play important roles in bacterial pathogenesis.

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