The concern over the possible reemergence of severe invasive diseases caused by Streptococcus pyogenes (group A streptococcus) has focused attention on the role of its secreted cysteine protease in pathogenesis. Unfortunately and despite extensive application of modern genetic technology, various studies have both supported and refuted an important role for the protease in promoting disease. Thus, the role of the cysteine protease in pathogenesis remains unclear. It is likely that much of the controversy has arisen because the biogenesis of the cysteine protease is only poorly understood. However, it is clear that this process is highly regulated, both at the level of transcription and at the level of processing the secreted inactive pro-protein to the active form. My lab has begun to address this issue and developed a novel transposon to identify three loci required for expression of proteolytic activity. Designated as Rop loci (regulation of protease), ropB is an activator of transcription of the gene which encodes the protease and is a member of the emerging Rgg-like family of regulators of which very little is currently known. In contrast, ropA contributes to secretion and processing of the protease and encodes a homologue of Trigger Factor, a peptidyl-prolyl isomerase and putative chaperone, which is highly conserved in most bacterial species, but of unknown function. Preliminary studies have shown that RopA acts both to assist in targeting the protease to the secretory pathway and in promoting the ability of the proprotein to establish an active conformation upon secretion.
The Specific Aims will address 1.) the function of ropC, including whether it is involved in transcription, secretion or processing of protease; 2.) Further characterization of RopB, focusing on its possible interactions with the multiple promoters for the gene which encodes the protease; 3.) an in-depth analysis of the role of RopA in secretion and folding of the protease precursor; and 4.) An examination of the role of the Rop loci in virulence in a murine model of streptococcal infection. The proposed studies will utilize recently developed state-of-the-art methodologies for analysis in S. pyogenes and the further characterization of these genes will be important for understanding the function of the protease through understanding when and where it is expressed during infection.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI046433-05
Application #
6692620
Study Section
Bacteriology and Mycology Subcommittee 2 (BM)
Program Officer
Rubin, Fran A
Project Start
2000-01-15
Project End
2004-12-31
Budget Start
2004-01-01
Budget End
2004-12-31
Support Year
5
Fiscal Year
2004
Total Cost
$299,900
Indirect Cost
Name
Washington University
Department
Microbiology/Immun/Virology
Type
Schools of Medicine
DUNS #
068552207
City
Saint Louis
State
MO
Country
United States
Zip Code
63130
Port, Gary C; Cusumano, Zachary T; Tumminello, Paul R et al. (2017) SpxA1 and SpxA2 Act Coordinately To Fine-Tune Stress Responses and Virulence in Streptococcus pyogenes. MBio 8:
Port, Gary C; Paluscio, Elyse; Caparon, Michael G (2015) Complete Genome Sequences of emm6 Streptococcus pyogenes JRS4 and Parental Strain D471. Genome Announc 3:
Port, Gary C; Vega, Luis A; Nylander, Andrew B et al. (2014) Streptococcus pyogenes polymyxin B-resistant mutants display enhanced ExPortal integrity. J Bacteriol 196:2563-77
Port, Gary C; Paluscio, Elyse; Caparon, Michael G (2013) Complete Genome Sequence of emm Type 14 Streptococcus pyogenes Strain HSC5. Genome Announc 1:
Vega, Luis Alberto; Port, Gary C; Caparon, Michael G (2013) An association between peptidoglycan synthesis and organization of the Streptococcus pyogenes ExPortal. MBio 4:e00485-13
Guiton, Pascale S; Hannan, Thomas J; Ford, Bradley et al. (2013) Enterococcus faecalis overcomes foreign body-mediated inflammation to establish urinary tract infections. Infect Immun 81:329-39
Vega, Luis Alberto; Caparon, Michael G (2012) Cationic antimicrobial peptides disrupt the Streptococcus pyogenes ExPortal. Mol Microbiol 85:1119-32
Guiton, Pascale S; Cusumano, Corinne K; Kline, Kimberly A et al. (2012) Combinatorial small-molecule therapy prevents uropathogenic Escherichia coli catheter-associated urinary tract infections in mice. Antimicrob Agents Chemother 56:4738-45
Guiton, Pascale S; Hung, Chia S; Hancock, Lynn E et al. (2010) Enterococcal biofilm formation and virulence in an optimized murine model of foreign body-associated urinary tract infections. Infect Immun 78:4166-75
Kline, Kimberly A; Kau, Andrew L; Chen, Swaine L et al. (2009) Mechanism for sortase localization and the role of sortase localization in efficient pilus assembly in Enterococcus faecalis. J Bacteriol 191:3237-47

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