Perspective: peptides as mimics of transmembrane segments in proteins

Peptide-based approaches to protein structure within membranes have proven enormously valuable. When one focusses on the detailed manner through which membrane proteins actually traverse the cell bilayer, a simple observation emerges: helical peptide segments of 20 amino acids each constitute the on ly tangible connection between the inside and outside of the cell. Thus, a major step towards understanding the key relationships between biological f unction and membrane protein structure can be taken through characterizatio n, by composition, sequence, chain length, hydrophobicity and conformation, of hydrophobic peptides designed as mimics of transmembrane segments.