Question

Which of the following is not correct about the Integral Membrane Proteins?

(a) Membrane proteins exist in lipid bilayers of cell membranes

(b) The exterior of the proteins spanning the membrane must be very hydrophobic to be stable

(c) The exterior of the proteins spanning the membrane must be very hydrophilic to be stable

(d) Most typical transmembrane segments are α-helices

The question was asked by my school teacher while I was bunking the class.

This interesting question is from Protein Structure Basics topic in portion Structural Bioinformatics of Bioinformatics

Answer 1

Correct choice is (c) The exterior of the proteins spanning the membrane must be very hydrophilic to be stable

For explanation: Because they are surrounded by lipids, the exterior of the proteins spanning the membrane must be very hydrophobic to be stable. Occasionally, for some bacterial periplasmic membrane proteins, they are composed of β-strands. The loops connecting these segments sometimes lie in the aqueous phase, in which they can be entirely hydrophilic.