<p>The structure consists of 13 α-helices and 11 β-strands, representing a classic Rossmann fold architecture. The secondary structures are shown in different colours and are labelled with the corresponding numbers. (A) Side view. (B) Top view. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0026743#pone-0026743-g001" target="_blank">Figures 1</a>–<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0026743#pone-0026743-g002" target="_blank"></a><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0026743#pone-0026743-g003" target="_blank"></a><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0026743#pone-0026743-g004" target="_blank">4</a> were made using PyMOL (DeLano Scientific, Palo Alto, California, USA; <a href="http://www.pymol.org" target="_blank">http://www.pymol.org</a>).</p
