Staphylococcus aureus is a versatile human pathogen that is responsible for both healthcare-associated infections and, increasingly, community acquired disease. S. aureus causes a wide range of diseases, from minor skin and soft tissue infections to more serious disorders including pneumonia, toxic shock, osteomyelitis and endocarditis. It is commonly found associated with infection of indwelling medical devices and surgical wounds. The emergence of aggressive strains resistant to multiple antibiotics, in combination with widespread horizontal gene transfer, poses a significant public health hazard. The ability of S. aureus to adapt rapidly to antibiotic pressure underscores the need for continued development of new targets for antimicrobial therapy. Recent work in our laboratory has led to the discovery that one of the proteins in the large subunit of the ribosome is subject t a specific N-terminal cleavage in S. aureus and other Gram positive bacteria. Several lines of evidence are consistent with the hypothesis that this cleavage event is essential. Bioinformatic and biochemical studies have led to the identification of the protease responsible for this cleavage. This proposal includes a combination of genetic and biochemical approaches to confirm the requirement for cleavage and the characterization of the protease. We will develop a cleavage assay and identify key amino acid residues in the protease and in the ribosomal protein that are necessary for this targeted cleavage event. These studies will elucidate the role of this novel ribosomal protein processing event and set the stage for subsequent efforts aimed at the development of a new class of antibiotics that will inhibit this cleavage reaction.

Public Health Relevance

Staphylococcus aureus strains cause a variety of life-threatening illnesses, such as necrotizing pneumonia, toxic shock syndrome and endocarditis. The emergence of highly virulent S. aureus strains that are resistant to multiple antibiotics has become a significant public health problem, both in hospitals and in the community. The proposed research investigates a newly identified cleavage step that is thought be essential for proper assembly/function of the S. aureus ribosome and provides a novel target for the development of new antibiotics to treat S. aureus infections.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Exploratory/Developmental Grants (R21)
Project #
1R21AI109202-01A1
Application #
8768939
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Huntley, Clayton C
Project Start
2014-07-15
Project End
2016-06-30
Budget Start
2014-07-15
Budget End
2015-06-30
Support Year
1
Fiscal Year
2014
Total Cost
Indirect Cost
Name
Virginia Commonwealth University
Department
Microbiology/Immun/Virology
Type
Schools of Medicine
DUNS #
City
Richmond
State
VA
Country
United States
Zip Code
23298
Wall, Erin A; Johnson, Adam L; Peterson, Darrell L et al. (2017) Structural modeling and functional analysis of the essential ribosomal processing protease Prp from Staphylococcus aureus. Mol Microbiol 104:520-532
Wall, Erin A; Caufield, J Harry; Lyons, Charles E et al. (2015) Specific N-terminal cleavage of ribosomal protein L27 in Staphylococcus aureus and related bacteria. Mol Microbiol 95:258-69