X‐ray reflectivity study of a transcription‐activating factor‐derived peptide penetration into the model phospholipid monolayers

Abstract

Abstract:The penetration of a transcription-activating factor (TAT)-derived, cell-penetration peptide onto 1,2-dipalmitoyl-snglycero-3-phosphocholine (DPPC) or 1,2-dipalmitoyl-sn-glycero-3-[phospho-L-serine] (DPPS) monolayer on phosphate-buffered saline subphase was characterized. The surface area at the target pressure increased noticeably by the peptide penetration from the subphase to the phospholipid monolayer, which might suggest a direct penetration of the peptide across the pure phospholipid bilayer membrane. Interestingly, the more significant area increase at 35 mN/m was monitored from DPPC monolayer, contrary to the simple charge interaction: the net neutral DPPC, the net-negative DPPS, and the positive TAT-derived peptides (TDP). X-ray reflectivity measurements as well as the molecular area from π (surface pressure)-A (area) isotherms suggest that the packing density of DPPS at the target pressure is too high to allow the effective penetration of the peptide into the monolayer and the positively charged peptides can be entrapped at the negative electrostatic well of DPPS headgroup layer, leading to the simple adsorption on the DPPS monolayer instead of penetration into it. Thus, more penetration with less adsorption of the peptide is induced by DPPC monolayer than DPPS monolayer.

Mimicking the receptor-aided binding of HIV-1 TAT protein transduction domains to phospholipid monolayers at the air–water interface

“…In contrast, as indicated by our previous report, 21 TAT-TDP does not adsorb onto highly compressed ($35 mN m À1 ) solid phase lipid monolayers, contrary to simple charge interactions between lipids and peptides. In that case, we speculated that the packing density of lipids was too high to allow the effective penetration of the peptides into the monolayer.…”

“…20 Recently, we characterized the adsorption of TAT-derived peptides into model lipid monolayers, composed of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) or 1,2-dipalmitoylsn-glycero-3-phosphoserine (DPPS), to elucidate the binding affinities of TAT-derived cell penetrating peptides (CPPs). 21 We observed very interesting results, suggesting that a direct insertion did not necessarily correspond to an electrostatic interaction with the bare cell membrane. In spite of a larger electrostatic driving force between negatively charged DPPS and the positive TAT-derived CPP, we found less penetration and simple adsorption of the peptide by a DPPS monolayer than by a zwitterionic DPPC monolayer.…”

Neutron and X-ray scattering for biophysics and biotechnology: examples of self-assembled lipid systems

“…74 Several proteins have been tested for their ability to penetrate the lipid environment by reflectivity. This has led to some interesting discoveries, such as a critical lateral pressure for the insertion of a transcription activating factor derived peptide 75 a peptide which acts as an agent capable of ferrying cargo across cell membranes. Another study of membrane adsorbed peptide structure utilized partially folded a helix motifs that interacted with lipid monolayers through divalent metal ion-histidine interactions.…”

Phase separation of phospholipid multilayers incorporated with cell penetrating peptides

“…[20][21][22] Substrate-supported lipid/CPP multilayers, with TDP being used as the CPP, were prepared by using the self-assembled method, and the structures of the mixed lipid multilayers with TDP incorporated were explored. We varied the DPPC-to-DPPS molar ratio while keeping the DPPC content fixed and changing the DPPS content, and we compared the structure of the lipid/TDP mixed multilayer with that of the mixed lipid multilayer without TDP for various contents of DPPS ͑net-negatively-charged lipids͒ by using X-ray reflectivity.…”