A structure which contains two of these elements sandwiched together has a characteristic heptad repeat.
These structures have a 3J Hahn coefficients of either 3.9 or 6.9 Hertz in NMR spectroscopy. Melting of poly-lysine molecules are used to study the properties of these structures, transitions to which are studied by the transfer-matrix-based Lifson-Roig model. A structure which contains two of these elements sandwiched together has a characteristic heptad repeat. This structure displays sharp minima at 208 and 222 nanometers in circular dichrosim spectroscopy. This structure is inferred when several residues clump in an area between the 2nd and third quadrants of a Ramachandran plot. This structure has hydrogen bonds between the ith and i-plus-fourth position, and has a pitch of 5.4 angstroms. For 10 points, name this protein secondary structure which is contrasted with the beta sheet.
These structures have a 3J Hahn coefficients of either 3.9 or 6.9 Hertz in NMR spectroscopy.
alpha helix [prompt on helix]