title: Time-lapse atomic force microscopy observations of the morphology, growth rate, and spontaneous alignment of nanofibers containing a peptide-amphiphile from the hepatitis G virus (NS3 protein).
abstract: Time-lapse atomic force microscopy is used in this contribution to directly watch the growth of nanofibers of a lipidated peptide on a mica surface. Specifically, the studied lipopeptide is the palmitoyl derivative of the fragment 505-514 of NS3 protein from the hepatitis G virus, abbreviated as Palmitoyl-NS3 (505-514). Data on the morphology, growth rate, and orientation of these peptide-amphiphile nanofibers have been obtained. From these data, it can be concluded that this synthetic lipopeptide forms two types of fiber-like aggregates: (i) half-spherical fibrous aggregates with lengths of hundreds of nanometers and (ii) spherical fibrous aggregates with lengths of several micrometers. In addition, when a fresh lipopeptide aqueous solution is deposited onto a mica surface, the aggregates spontaneously orient parallel to each other, yielding well-aligned nanofibers on large areas of the mica surface. A significant growth in both the length and the number of the fibers was observed during the first minutes after the solution deposition. Elongation of the fibrous aggregates from one end is more frequent, though elongation from both ends also occurs, with growth rates in the 4-5 nm/s range. The effects of dilution, mechanical perturbation, and pH on the aggregation behavior of Palmitoyl-NS3 (505-514) are also detailed in this paper.
authors.affiliation: Department of Physical Chemistry, Faculty of Pharmacy, University of Barcelona, Av. Joan XXII s/n, 08028 Barcelona, Spain. weronski@ub.edu
authors.forename: Konrad J
authors.initials: KJ
authors.lastname: Weroński
authors.forename: Pilar
authors.initials: P
authors.lastname: Cea
authors.forename: Ismael
authors.initials: I
authors.lastname: Diez-Peréz
authors.forename: Maria Antonia
authors.initials: MA
authors.lastname: Busquets
authors.forename: Josefina
authors.initials: J
authors.lastname: Prat
authors.forename: Victoria
authors.initials: V
authors.lastname: Girona
mesh_terms: D000538:Aluminum Silicates / Q000737:chemistry; D029407:GB virus C; D018625:Microscopy, Atomic Force; D057139:Nanofibers / Q000737:chemistry*; D010168:Palmitates / Q000737:chemistry; D010455:Peptides / Q000737:chemistry; D013997:Time Factors; D017361:Viral Nonstructural Proteins / Q000737:chemistry*
chemical_list: D000538:Aluminum Silicates; D010168:Palmitates; D010455:Peptides; D017361:Viral Nonstructural Proteins; C011934:mica