Antimicrobial peptides protegrin

Solid-state NMR was used to study the activity of an antimicrobial peptide, protegrin-1, on lipid membranes. The degree on alignment of the membrane surface was determined. 

Lam et al. [57] smdied the antimicrobial peptide protegrin-1 in a membrane by atomic force microscopy (AFM) and MD methods. This 18 amino acid peptide contains six Arg residues and created edge instabihties in low concentrations and wormhole stmcmre in high concentrations. 

The interaction of a (3-hairpin antimicrobial peptide, protegrin-1, with various lipid membranes has been investigated by solid-state P, and NMR. Mixed lipid bilayers containing anionic lipids and cholesterol were used to mimic the bacterial and mammalian cell membranes, respectively. P and spectra of macroscopically oriented samples showed that protegrin-1 induces the formation of an isotropic phase in anionic bilayers containing phosphatidylglycerol. 2D P exchange, H spin diffusion and relaxation time measurements were undertaken. In a related work the results of solid-state H, C, N and P NMR studies of the selective perturbation of lipid bilayers by the cyclic antimicrobial peptide have been presented. ... 

Examples of studies on specific peptides and proteins in membranes are an SS NMR investigation of the selective disruption of lipid membranes by p-hairpin antimicrobial peptide protegrin-1 in multinuclear mixed lipid layer PG and PC +/ cholesterol MAS/NMR studies of apolipoprotein A1 mimetic peptides in PC membranes with cholesterol with a comparison of the interactions of two 18-mers with the same composition but different sequence with the membrane the peptide sequence GSSSGRGDSPA having a hydrophobic extender to the N-terminus was studied with dextran oligosaccharides and hexyl ligands boimd onto a polyvinylamine backbone to mimic interactions at the ECM. ... 

A different example of the use of paramagnetic relaxation for distance measurements was provided by the determination of the depth of insertion of the antimicrobial peptide protegrin-1 into lipid bilayer membranes [102]. By doping... 

Fahrner, R.L, Dieckmann, T Harwig, S.S.L., Lehrer, R.I., Eisenberg, D and Feigon, J. (1996) Solution structure of protegrin-1, a broad-spectrum antimicrobial peptide from porcine leukocytes. Chem. Biol. (London) 3, 543-550. 

Frece, V. (2006) QSAR analysis of antimicrobial and haemolytic effects of cyclic cationic antimicrobial peptides derived from protegrin-1. Bioorgan. Medic. Chem. 14, 6065-6074. 

Kwon et al. used NMR to investigate domain formation in membranes (phosphatidylethanolamine (POPE) and anionic l-palmitoyl-2-oleoyl-s -gZycero-3-phosphatidylglycerol (POPG)) with to cationic peptides. The antimicrobial peptides were (AMP(3)) of the beta-hairpin family of protegrin-1 (PG-1), and two cell-penetrating peptides (CPPs), HIV TAT and penetratin. The NMR showed the extent of the interaction between the bilayers and the peptides. 

Lehrer, R. I., Ganz, T. Endogenous vertebrate antibiotics. Defensins, protegrins and other cysteine-rich antimicrobial peptides. Arm NY Acad Set. 19%, 797,228-239. 

An example of a simple CZE method for peptide analysis and characterization is the one developed for protegrin IB-367.37 IB-367 is a peptide containing 17 amino acid residues that possess antimicrobial properties, and it is being developed for treatment of oral mucositis associated with aggressive cancer chemotherapy as well as other topical applications. This polycationic product was chemically synthesized using solid-phase and purified by preparative reversed-phase HPLC. IB-367 is rich in cysteine and arginine residues. 

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