The presence of these structures can be identified on hydrophilicity (15[1])or hydrophobicity plots by a stretch of 20 positive values on the Kyte–Doolittle (15[1])scale. (15[1])A double (15[1])minimum at 208 and 222 nanometers in circular (15[1])dichroism spectroscopy (15[2])is used to identify these structures. (15[2]-5[2])These structures have square-like cross sections that allow them to be differentiated from similar structures (-5[1])named for “310” (-5[1])and pi. (-5[1])Two of these (-5[1])structures (-5[1])are dimerized in the DNA-binding leucine zipper (15[2])motif. (*) Glycine (-5[1])and proline (-5[1])are called (10[2])“breakers” (10[1])of these (-5[1])structures. (10[3]-5[2])A diagonal (10[1])cluster (10[1])on (10[1])Ramachandran (10[1]-5[1])plots (10[1])around (10[1])dihedral angles (10[1]-5[1])of −60 (“negative 60”) and −45 (“negative 45”) degrees (-5[1])identifies (-5[1])these structures. (10[1]-5[3])Hydrogen bonds stabilize the 3.6 residues (10[1])per turn (10[2])characteristic (10[1])of these structures. (10[1]-5[2])For 10 points, name this (10[1])coiled secondary (10[1]-5[1])structure motif (-5[1])in proteins (10[1])that is more (10[1])common (10[2])than (10[1])beta (10[1])sheets. (10[1])■END■ (10[15]0[7])