Proposed tertiary structure for the hypothalamic thyrotropin-releasing factor.
Semiempirical energy calculations were performed to determine the conformation of the thyrotropin-releasing factor, L-pyroglutamyl-L-histidyl-L-prolineamide. Our results strongly suggest a "hairpin turn" conformation stabilized by two specific hydrogen bonds. Experimental support for this structure was obtained from proton magnetic resonance by use of chemical shifts and coupling constants with the implied dihedral angles.
Magnetic Resonance Spectroscopy↗