Arginine-based surfactants alter the rheological and in-plane structural properties of stratum corneum model membranes.

Hypothesis: Amino acid-based surfactants have been proposed as skin permeation enhancers. In this work, we investigated the potentiality of two arginine-based amphiphiles as permeation enhancers by studying their interaction with stratum corneum (SC) model lipid membranes.

Experiments: N-benzoyl arginine decyl- and dodecylamide were tested in comparison with the classical enhancer, oleic acid, and the non-enhancer, stearic acid.

Histidine 19 Residue Is Essential for Cell Internalization of Antifungal Peptide SmAP Derived from the α-Core of the Defensin DefSm2-D in .

The synthetic peptide SmAP (KLCEKPSKTWFGNCGNPRHCG) derived from DefSm2-D defensin α-core is active at micromolar concentrations against the phytopathogenic fungus and has a multistep mechanism of action that includes alteration of the fungal cell wall and membrane permeabilization. Here, we continued the study of this peptide's mode of action and explored the correlation between the biological activity and its primary structure. Transmission electron microscopy was used to study the ultrastructural effects of SmAP in conidial cells.

Gravity Threshold and Dose Response Relationships: Health Benefits Using a Short Arm Human Centrifuge.

Purpose: Increasing the level of gravity passively on a centrifuge, should be equal to or even more beneficial not only to astronauts living in a microgravity environment but also to patients confined to bed. Gravity therapy (GT) may have beneficial effects on numerous conditions, such as immobility due to neuromuscular disorders, balance disorders, stroke, sports injuries. However, the appropriate configuration for administering the Gz load remains to be determined.

Interaction of cationic surfactants with DPPC membranes: effect of a novel N-benzoylated arginine-based compound.

Cationic amino acid-based surfactants are known to interact with the lipid bilayer of microorganism resulting in cell death through a disruption of the membrane topology. To elucidate the interaction of a cationic surfactant synthesized in our lab, investigations involving N-benzoyl-arginine decyl amide (Bz-Arg-NHC), and model membranes composed by 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) were done. Bz-Arg-NHCwas able to penetrate into DPPC monolayers up to a critical pressure of 59.

Peptides Derived From the α-Core and γ-Core Regions of a Putative Flower Defensin Show Antifungal Activity Against .

is the etiological agent of Fusarium head blight (FHB), a disease that produces a significant decrease in wheat crop yield and it is further aggravated by the presence of mycotoxins in the affected grains that may cause health problems to humans and animals. Plant defensins and defensin-like proteins are antimicrobial peptides (AMPs); they are small basic, cysteine-rich peptides (CRPs) ubiquitously expressed in the plant kingdom and mostly involved in host defence. They present a highly variable sequence but a conserved structure.