Crystal structure of YwpF from Staphylococcus aureus reveals its architecture comprised of a β‐barrel core domain resembling type VI secretion system proteins and a two‐helix pair

The ywpF gene (SAV2097) of the Staphylococcus aureus strain Mu50 encodes the YwpF protein, which may play a role in antibiotic resistance. Here, we report the first crystal structure of the YwpF superfamily from S. aureus at 2.5‐Å resolution. The YwpF structure consists of two regions: an N‐terminal core β‐barrel domain that shows structural similarity to type VI secretion system (T6SS) proteins (e.g., Hcp1, Hcp3, and EvpC) and a C‐terminal two‐helix pair. Although the monomer structure of S. aureus YwpF resembles those of T6SS proteins, the dimer/tetramer model of S. aureus YwpF is distinct from the functionally important hexameric ring of T6SS proteins. We therefore suggest that the S. aureus YwpF may have a different function compared to T6SS proteins. Proteins 2015; 83:781–788. © 2015 Wiley Periodicals, Inc.