Application of Nuclear Magnetic Resonance Based Metabolomics to Study the Central Metabolism of Staphylococci

Ribose phosphate isomerase R (RpiR) is a transcriptional regulatory protein involved in the pentose phosphate pathway. Inactivation of the TCA cycle increases carbon flow into the pentose phosphate pathway where the RpiR protein family may be involved. In S. aureus, mutations of intracellular ribose sensing regulators (members of the RpiR family) resulted in changes in the synthesis of virulence factors. The inducer for ribose phosphate isomerase A, B and the mechanism by which RpiRa regulates rpiA, rpiB gene expression remain to be elucidated. The C-terminal domain of RpiRa was predicted to be a sugar isomerase binding protein domain using homology modeling and it was overexpressed and purified using an E. coli pET overrexpression system as a first step towards the structural determination of this protein.