Molecular Dynamics of Peptide Folding at Aqueous InterfacesEven though most monomeric peptides are disordered in water they can adopt sequence-dependent, ordered structures, such as a-helices, at aqueous interfaces. This property is relevant to cellular signaling, membrane fusion, and the action of toxins and antibiotics. The mechanism of folding nonpolar peptides at the water-hexane interface was studied in the example of an 11-mer, of poly-L-leucine. Initially placed as a random coil on the water side of the interface, the peptide folded into an a-helix in 36 ns. Simultaneously, the peptide translocated into the hexane side of the interface. Folding was not sequential and involved a 3/10-helix as an intermediate. The folded peptide was either parallel to the interface or had its C-terminus exposed to water. An 11-mer, LQQLLQQLLQL, composed of leucine (L) and glutamine (G), was taken as a model amphiphilic peptide. It rapidly adopted an amphiphilic, disordered structure at the interface. Further folding proceeded through a series of amphiphilic intermediates.
Document ID
20020052414
Acquisition Source
Ames Research Center
Document Type
Conference Paper
Authors
Pohorille, Andrew (NASA Ames Research Center Moffett Field, CA United States)
Chipot, Christophe (NASA Ames Research Center Moffett Field, CA United States)
Chang, Sherwood
Date Acquired
August 20, 2013
Publication Date
January 1, 1997
Subject Category
Life Sciences (General)
Meeting Information
Meeting: American Chemical Society National Meeting