2.B.45. The pH low insertion peptide (pHLIP) Family
The applications of the pH low insertion peptide (pHLIP) in cancer diagnosis and cross-membrane cargo delivery have been reported. With its origin as the transmembrane (TM) helix C of bacteriorhodopsin, pHLIP is also an important model for understanding how pH can affect the folding and topogenesis of a TM alpha-helix. Protonations of multiple D/E residues transform pHLIP from an unstructured coil at the membrane surface (known as state II, at pH >/= 7) to a TM alpha-helix (state III, pH) has been described (Otieno et al. 2018).