title: Evolutionary Constraints Shaping Streptococcus pyogenes-Host Interactions.
abstract: Research on the Gram-positive human-restricted pathogen Streptococcus pyogenes (Group A Streptococcus, GAS) has long focused on invasive illness, the most severe manifestations of GAS infection. Recent advances in descriptions of molecular mechanisms of GAS virulence, coupled with massive sequencing efforts to isolate genomes, have allowed the field to better understand the molecular and evolutionary changes leading to pandemic strains. These findings suggest that it is necessary to rethink the dogma involving GAS pathogenesis, and that the most productive avenues for research going forward may be investigations into GAS in its 'normal' habitat, the nasopharynx, and its ability to either live with its host in an asymptomatic lifestyle or as an agent of superficial infections. This review will consider these advances, focusing on the natural history of GAS, the evolution of pandemic strains, and novel roles for several key virulence factors that may allow the field to better understand their physiological role.
authors.affiliation: Department of Microbiology and Immunology, University of Illinois at Chicago, Chicago, IL 60607, USA; Center for Biomolecular Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA.
authors.forename: Reid V
authors.initials: RV
authors.lastname: Wilkening
authors.affiliation: Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, Chicago, IL 60607, USA; Center for Biomolecular Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA. Electronic address: mfederle@uic.edu.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Federle
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D019143:Evolution, Molecular; D015964:Gene Expression Regulation, Bacterial; D054884:Host-Pathogen Interactions; D006801:Humans; D009092:Mucous Membrane / Q000382:microbiology; D065288:Serogroup; D013290:Streptococcal Infections / Q000382:microbiology*; D013297:Streptococcus pyogenes / Q000235:genetics* / Q000472:pathogenicity / Q000502:physiology; D014774:Virulence; D037521:Virulence Factors
chemical_list: D001426:Bacterial Proteins; D037521:Virulence Factors
keywords: Bottleneck; Epidemic serotypes; In vivo selection; Mucosa; Pathogen evolution; Sterile-site infection