Staphylococcus aureus (S. aureus) is the causative agent of a range of illnesses from minor skin infection to life-threatening diseases. This bacterium has a unique sulfur metabolism pathway as it cannot utilize sulfate as a sulfur source but can grow on thiosulfate and sulfide. Sulfur is required to make cysteine as well as other sulfur containing metabolites. Furthermore, disruptions in the sulfur metabolic pathway decrease S. aureus ability to make biofilms. The cst operon was recently discovered in S. aureus and may be involved in sulfur assimilation, sulfur trafficking and/or sulfide detoxification. The cst operon encodes five different proteins: TauE, CstR, CstA, CstB and SQR. This work focuses on CstA, a putative sulfur transferase containing three domains, a Rhodanese (RHOD), TusA, and DsrE/TusD domain. All three domains possess a single cysteine residue, Cys66, Cys128 and Cys316, respectively that may be involved in the shuttling of sulfur as cysteine persulfides to downstream targets. We have initiated experiments to solve the solution structure of the CstARHOD-TusA two-domain protein using NMR methods. Nearly complete backbone 13C�, 13Ca, 13C0, 15N and 1HN resonances are now in hand for CstARHOD-TusA. These studies reveal that C66 and C128 are within disulfide bonding distance, consistent with a persulfide shuttling model and the TusA and RHOD domains pack against one another and tumble in solution as a single globular domain. Progress toward the solution structure and identification of cellular CstA interacting proteins will be reported.Supported by NIH grant GM097225 to D.P.G..

Probing the structure and dynamics of CstA from<i> Staphylococcus aureus</i>

246th National Meeting (2013)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.

Probing the structure and dynamics of CstA from Staphylococcus aureus