Journal: Membranes

Article Title: How Insertion of a Single Tryptophan in the N-Terminus of a Cecropin A-Melittin Hybrid Peptide Changes Its Antimicrobial and Biophysical Profile

doi: 10.3390/membranes11010048

Figure Lengend Snippet: Helical wheel projections of BP100 and W-BP100. Polar amino acid residues are in blue and non-polar ones in yellow. C and N represent the amino and carboxyl termini, respectively, and the arrows indicate the directions and magnitudes of the hydrophobic moments. Amino acid residues are represented by the single letter code as defined by the IUPAC-IUBMB guidelines on nomenclature and symbolism for amino acids and peptides. Helical wheel projections were generated in the HELIQUEST software .

Article Snippet: The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for W-BP100 and BP100 against susceptible reference strains ( Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 29213, and Enterococcus faecalis ATCC 29212) were determined by the broth microdilution method, following the Clinical and Laboratory Standards Institute (CLSI) guidelines [ ].

Techniques: Generated, Software

Journal: Membranes

Article Title: How Insertion of a Single Tryptophan in the N-Terminus of a Cecropin A-Melittin Hybrid Peptide Changes Its Antimicrobial and Biophysical Profile

doi: 10.3390/membranes11010048

Figure Lengend Snippet: Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for BP100 and W-BP100, against Gram-negative and Gram-positive susceptible reference bacterial species.

Article Snippet: The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for W-BP100 and BP100 against susceptible reference strains ( Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 29213, and Enterococcus faecalis ATCC 29212) were determined by the broth microdilution method, following the Clinical and Laboratory Standards Institute (CLSI) guidelines [ ].

Techniques: Concentration Assay

Journal: Membranes

Article Title: How Insertion of a Single Tryptophan in the N-Terminus of a Cecropin A-Melittin Hybrid Peptide Changes Its Antimicrobial and Biophysical Profile

doi: 10.3390/membranes11010048

Figure Lengend Snippet: Membrane partitioning of W-BP100 in anionic and zwitterionic model membranes determined by steady-state fluorescence spectroscopy. Representative fluorescence emission spectra of W-BP100 in presence of ( A ) POPC:POPG (1:1) and ( C ) POPC LUV. ( B , D ) Spectral lines of the non-linear fitting of experimental data to the simple partition model in Equation (2). Data points and error bars are the mean ± SD of three independent experiments.

Article Snippet: The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for W-BP100 and BP100 against susceptible reference strains ( Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 29213, and Enterococcus faecalis ATCC 29212) were determined by the broth microdilution method, following the Clinical and Laboratory Standards Institute (CLSI) guidelines [ ].

Techniques: Membrane, Fluorescence, Spectroscopy

Journal: Membranes

Article Title: How Insertion of a Single Tryptophan in the N-Terminus of a Cecropin A-Melittin Hybrid Peptide Changes Its Antimicrobial and Biophysical Profile

doi: 10.3390/membranes11010048

Figure Lengend Snippet: Membrane partition of peptides in anionic and zwitterionic LUV.

Article Snippet: The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for W-BP100 and BP100 against susceptible reference strains ( Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 29213, and Enterococcus faecalis ATCC 29212) were determined by the broth microdilution method, following the Clinical and Laboratory Standards Institute (CLSI) guidelines [ ].

Techniques: Membrane

Journal: Membranes

Article Title: How Insertion of a Single Tryptophan in the N-Terminus of a Cecropin A-Melittin Hybrid Peptide Changes Its Antimicrobial and Biophysical Profile

doi: 10.3390/membranes11010048

Figure Lengend Snippet: Membrane partitioning of BP100 in anionic and zwitterionic model membranes determined by steady-state fluorescence spectroscopy. Representative fluorescence emission spectra of BP100 as a function of ( A ) POPC:POPG (1:1) and ( B ) POPC LUV. ( C ) Spectral lines of the non-linear fitting of experimental data to the simple partition model in Equation (1). Data points and error bars are the mean ± SD of two to three independent experiments.

Article Snippet: The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for W-BP100 and BP100 against susceptible reference strains ( Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 29213, and Enterococcus faecalis ATCC 29212) were determined by the broth microdilution method, following the Clinical and Laboratory Standards Institute (CLSI) guidelines [ ].

Techniques: Membrane, Fluorescence, Spectroscopy

Journal: Membranes

Article Title: How Insertion of a Single Tryptophan in the N-Terminus of a Cecropin A-Melittin Hybrid Peptide Changes Its Antimicrobial and Biophysical Profile

doi: 10.3390/membranes11010048

Figure Lengend Snippet: W-BP100-induced membrane saturation in POPC:POPG (1:1) LUV. ( A ) Titration of POPC:POPG (1:1) LUV in HEPES buffer, containing 100 mmol dm −3 acrylamide, with increasing concentrations of W-BP100, at 25 ± 0.1 °C, as described by Melo et al. . The breaking points in each curve, where a change of slope is observed, represent membrane saturation points. The fluorescence spectra of each titration are reported in the . ( B ) Plotting of W-BP100 and POPC:POPG (1:1) concentrations at saturation points, and fitting to the membrane saturation model Equation (2). Data points and error bars represent the mean ± SD of three independent experiments.

Article Snippet: The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for W-BP100 and BP100 against susceptible reference strains ( Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 29213, and Enterococcus faecalis ATCC 29212) were determined by the broth microdilution method, following the Clinical and Laboratory Standards Institute (CLSI) guidelines [ ].

Techniques: Membrane, Titration, Fluorescence

Journal: Membranes

Article Title: How Insertion of a Single Tryptophan in the N-Terminus of a Cecropin A-Melittin Hybrid Peptide Changes Its Antimicrobial and Biophysical Profile

doi: 10.3390/membranes11010048

Figure Lengend Snippet: Acrylamide quenching of peptide fluorescence in aqueous solution and in the presence of LUV. Quenching of fluorescence of ( A ) BP100 and ( B ) W-BP100 in HEPES buffer and in the presence of POPC:POPG (1:1) and POPC LUV. Experimental data was fitted to the Stern–Volmer equation for collisional quenching, Equation (3). Data points and error bars are the Mean ± SD of three independent experiments. The fluorescence spectra for each condition are reported in the .

Article Snippet: The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for W-BP100 and BP100 against susceptible reference strains ( Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 29213, and Enterococcus faecalis ATCC 29212) were determined by the broth microdilution method, following the Clinical and Laboratory Standards Institute (CLSI) guidelines [ ].

Techniques: Fluorescence

Journal: Membranes

Article Title: How Insertion of a Single Tryptophan in the N-Terminus of a Cecropin A-Melittin Hybrid Peptide Changes Its Antimicrobial and Biophysical Profile

doi: 10.3390/membranes11010048

Figure Lengend Snippet: Stern–Volmer constants ( K SV ) determined for the quenching of BP100 and W-BP100 by acrylamide in the absence and presence of LUV, by fitting the experimental data to the Stern–Volmer equation for collisional quenching, Equation (3). The presented values are the Mean ± SD of at least three independent experiments.

Article Snippet: The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for W-BP100 and BP100 against susceptible reference strains ( Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 29213, and Enterococcus faecalis ATCC 29212) were determined by the broth microdilution method, following the Clinical and Laboratory Standards Institute (CLSI) guidelines [ ].

Techniques:

Journal: Membranes

Article Title: How Insertion of a Single Tryptophan in the N-Terminus of a Cecropin A-Melittin Hybrid Peptide Changes Its Antimicrobial and Biophysical Profile

doi: 10.3390/membranes11010048

Figure Lengend Snippet: Size distribution of anionic LUV in the presence of increasing peptide concentrations. Number-weighted size distribution of 100 µmol dm −3 POPC:POPG (1:1) LUV in ( A ) absence and presence of 0–15 µmol dm −3 ( B ) BP100 and ( C ) W-BP100. Data are the mean of size distribution ± SD of at least three independent experiments.

Article Snippet: The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for W-BP100 and BP100 against susceptible reference strains ( Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 29213, and Enterococcus faecalis ATCC 29212) were determined by the broth microdilution method, following the Clinical and Laboratory Standards Institute (CLSI) guidelines [ ].

Techniques:

Journal: Membranes

Article Title: How Insertion of a Single Tryptophan in the N-Terminus of a Cecropin A-Melittin Hybrid Peptide Changes Its Antimicrobial and Biophysical Profile

doi: 10.3390/membranes11010048

Figure Lengend Snippet: Peptide-induced permeabilization of anionic model membranes. ( A , B ) Leakage kinetics of carboxyfluorescein (CF) release from 60 µmol dm −3 CF-loaded POPC:POPG (1:1) LUV in the presence of increasing concentrations of ( A , B ) BP100 and ( C , D ) W-BP100, along 30 minutes of incubation in HEPES buffer, at 25 ± 0.1 °C. Asterisks and arrows mark the time-points of peptide and Triton-X addition, respectively. ( E ) Percentage of CF release as function of peptide concentration and P/L ratio. LC 50 represents the peptide concentration that promotes 50% leakage of CF. Data points and error bars represent the mean ± SD of at least two independent experiments.

Article Snippet: The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for W-BP100 and BP100 against susceptible reference strains ( Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 29213, and Enterococcus faecalis ATCC 29212) were determined by the broth microdilution method, following the Clinical and Laboratory Standards Institute (CLSI) guidelines [ ].

Techniques: Incubation, Concentration Assay