The High-Precision Solution Structure of Yersinia Modulating Protein YmoA Provides Insight into Interaction with H-NS†

ABSTRACT: The high-resolution solution structure of Yersinia modulating protein YmoA is presented. The protein is all helical with the first three of four helices forming the central core. Structures calculated with only NOE and dihedral restraints exhibit a backbone root-mean-square deviation (rmsd) of 0.77 Å. Upon refinement against HR-CR, HN-N, and CR-C ′ J-modulated residual dipolar couplings, the backbone rmsd improves to 0.22 Å. YmoA has a high amino acid sequence identity to and a similar overall fold to Escherichia coli hemolysin expression modulating protein Hha; however, structural differences do occur. YmoA is also found to be structurally similar to the histone-like nucleoid structuring protein H-NS, indicating that YmoA may intercalate into higher-order H-NS suprastructuring by substituting for an H-NS dimer. Yersinia pestis, the microorganism responsible for the plague, is a top bioterrorism threat. Left untreated, Y. pestis-derived pneumonic infections have a mortality rate of greater than 90%. Administration of antibiotics is an effective countermeasure, but the development of antibiotic resistant strains poses a significant danger. This underscores the nee