Ribbon representation of the six αβα-core connectivity-based structural classes

<p><b>Copyright information:</b></p><p>Taken from "Topology of Type II REases revisited; structural classes and the common conserved core"</p><p></p><p>Nucleic Acids Research 2007;35(7):2227-2237.</p><p>Published online 16 Mar 2007</p><p>PMCID:PMC1874628.</p><p>© 2007 The Author(s)</p> The α-helices H1 and H2, and β-strands S1 to S5, constituting the αβα-core, are shown for superposed structures belonging to each one of the new structural classes: () Structures 1cfr, 1knvA, 1na6B, 1wtdB, 1dc1A, 2fokA, 1fiuA and 1qc9A for class I in stereo view; () 1sdoA, 2bamA and 1dfmA for class II; 1sa3A and 1ynmA for class III; () 1xhvA, 1b94A, 1iawA and 1dmuA for class IV in stereo view; () 3pviA for class V and 2ixs for class VI