SheetConstraint (T0309)H7 (T0309)F15 (T0309)T26 (T0309)D18 hbond (T0309)I9 1 SheetConstraint (T0309)N10 (T0309)F15 (T0309)K52 (T0309)V47 hbond (T0309)K12 1 SheetConstraint (T0309)I49 (T0309)E53 (T0309)V59 (T0309)N55 hbond (T0309)V51 1