Complete non-proline backbone resonance assignments of the S. aureus neutrophil serine protease inhibitor, EapH1.

The S. aureus extracellular adherence protein (Eap) and its homologs, EapH1 and EapH2, serve roles in evasion of the human innate immune system. EapH1 binds with high-affinity and inhibits the neutrophil azurophilic granule proteases neutrophil elastase, cathepsin-G and proteinase-3. Previous structural studies using X-ray crystallography have shown that EapH1 binds to neutrophil elastase and cathepsin-G using a globally similar binding mode. However, whether the same holds true in solution is unknown and whether the inhibitor experiences dynamic changes following binding remains uncertain. To facilitate solution-phase structural and biochemical studies of EapH1 and its complexes with neutrophil granule proteases, we have characterized EapH1 by multidimensional NMR spectroscopy. Here we report a total of 100% of the non-proline backbone resonance assignments of EapH1 with BMRB accession number 50,304.