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Updated: Jul 17, 2026

Measuring Peptide Translocation into Large Unilamellar Vesicles
Published on: January 27, 2012
Studies on the insolubility of a transmembrane peptide from signal peptide peptidase
Erik C B Johnson1, Stephen B H Kent
1Institute for Biophysical Dynamics, Department of Biochemistry and Molecular Biology, The University of Chicago, 920 East 58th Street, Chicago, Illinois 60637, USA.
Abstract:
We have undertaken fundamental studies on the solubility properties of a peptide derived from the fourth transmembrane (TM) domain of signal peptide peptidase, a 7-TM intramembrane-cleaving protease. We have found that by disfavoring secondary structure formation we are able to greatly improve the solubility, handling, and purification properties of this peptide. Our findings suggest that preventing secondary structure formation by reversible modification of the polypeptide backbone of hydrophobic transmembrane peptides may be a useful strategy for the total chemical protein synthesis of integral membrane proteins.
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