Monomeric, single-pass, transmembrane proteins span a membrane with a single alpha helix that has characteristic chemical properties in the region of the bilayer. Which of these 20 amino acid sequences listed below is the most likely candidate for such a transmembrane segment? Why aren’t the others? Explain the reasons for your choice.

A.I T L I Y F G V M A G V I G T I L L I S
B.I T P I Y F G P M A G V I G T P L L I S
C.I T E I Y F G R M A G V I G T D L L I S
D.I T P I Y F G F M A G V I G T F L L I S