Figure 1.

The GD box element. A: The double-psi barrel fold of VatN-N (PDB 1CZ4, residues 1–91) is shown in cartoon representation. α-helices are colored in yellow and β-strands in green. B: The double-psi barrel fold of VatN-N is shown in backbone representation. The unpaired hairpins (residues 34–44 and 77–87) from the two GD box elements are shown in red. C: The first GD box element from VatN-N (residues 34–44, 53–55) is shown. The positions corresponding to the type-II β-turn are marked. D: Detailed view of the hydrogen-bonding network of the first GD box element. [Color figure can be viewed in the online issue, which is available at www.interscience.wiley.com.]