Two copies of the gramicidin protein are shown here () arranged as they are believed to be when they form a channel through a lipid bilayer membrane[1]. The shape of the protein is shown transparent (ghostly), and a backbone trace connecting the alpha carbon atoms of each amino acid chain is opaque (solid). Toggle spin off to see transparency.
Show of the gramicidin protein chains.
(Most hydrogen atoms are omitted.)
Show . Notice how the hydrophobic lipid "tails" exclude water.
Water passes
.
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