Cellular uptake of an α-helical amphipathic model peptide with the potential to deliver polar compounds into the cell interior non-endocytically

Abstract

Evidence that multiple, probably non-endocytic mechanisms are involved in the uptake into mammalian cells of the alpha-helical amphipathic model peptide FLUOS-KLALKLALKALKAALKLA-NH2 (I) is presented. Extensive cellular uptake of N-terminally GC-elongated derivatives of I, conjugated by disufide bridges to differently charged peptides, indicated that I-like model peptides might serve as vectors for intracellular delivery of polar bioactive compounds. The mode of the cellular internalization of I comprising energy-, temperature-, pH- and ion-dependent as well as -independent processes suggests analogy to that displayed by small unstructured peptides reported previously (Oehlke et al., Biochim. Biophys. Acta 1330 (1997) 50-60). The uptake behavior of I also showed analogy to that of several protein-derived helical peptide sequences, recently found to be capable of efficiently carrying tagged oligonucleotides and peptides directly into the cytosol of mammalian cells (Derossi et al., J. Biol. Chem. 269 (1994) 10444-10450; Lin et al., J. Biol. Chem. 270 (1995) 14255-14258; Fawell et al., Proc. Natl. Acad. Sci. USA 91 (1994) 664-668; Chaloin et al., Biochemistry 36 (1997) 11179-11187; Vives et al., J. Biol. Chem., 272 (1997) 16010-16017).

Translocation of Analogues of the Antimicrobial Peptides Magainin and Buforin across Human Cell Membranes

“…At low temperature, where membranes are less fluid, the formation of the peptide-lipid supramolecular complex pore that requires membrane bending will be suppressed. The entry of a synthetic cationic amphipathic helix composed of 18 amino acid residues was also partially inhibited at low temperature (37), although this observation was attributed to the presence of multiple cell permeation mechanisms. Sai et al (32) reported that adsorptive-mediated endocytosis of a small basic peptide was partially inhibited at low temperature (32).…”

“…4A) may be related to these alterations in the cell surface. Alternatively, several translocation pathways including those that are energy-dependent may be present, as suggested for a synthetic cationic amphipathic helix (37). CONCLUSION We investigated the cellular uptake of the analogues of the two representative antimicrobial peptides, membrane-acting magainin 2 and nuclear targeting buforin 2, in comparison with the Tat-(47-57) peptide.…”

Uptake of cell‐penetrating peptides in yeasts

“…In order to quantify uptake we used a method described in [7]. Not only does it make it possible to separate internalized from extracellularly bound peptides but, importantly, this method also holds the capacity to discriminate intact from degraded peptides.…”

“…The cell suspension was then centrifuged at 3000 · g, the resulting supernatant, containing medium and non-internalized peptide, was removed and the pellet was washed with ice-cold PBS. Peptides attached to the extracellular surface of the plasma membrane were modified by addition of 2-nitroaniline, as described in [7]. Protein concentration was determined according to detergent compatible protein assay kit from BioRAD, Stockholm, Sweden.…”

Cell‐penetrating peptides: Nanocarrier for macromolecule delivery in living cells

“…The presence of amphipathic helixes with hydrophilic and hydrophobic faces is considered as an essential structural requirement for these peptides to cross the plasma membrane at neutral pH (23). Model amphipathic peptide (MAP) is an 18 amino acid peptide (KLALKLALKAL KAALKLA) and exhibits an a-helical structure (24). Pep-1 is the first commercial CPP (Chariot kit, Active Motif, USA) made available for the noncovalently transduction of proteins.…”