The transmembrane domains of the nicotinic acetylcholine receptor contain alpha-helical and beta structures.

摘要: The transmembrane domain of the nicotinic acetylcholine receptor (nAChR) from Torpedo californica electric tissue contains both alpha-helical and beta structures. secondary structure was investigated by Fourier transform infrared (FTIR) spectroscopy after extramembrane moieties protein extracellular intracellular sides membrane were removed proteolysis using proteinase K. composition this was: 50%, turns 40%, random 10%. alpha-helices are shown to be oriented with respect plane in a way allowing them span membrane, while no unidirectional for structures observed. These findings contradict previous models based on hydropathy plots alone.