The Experts below are selected from a list of 1074 Experts worldwide ranked by ideXlab platform
Christian Mestres - One of the best experts on this subject based on the ideXlab platform.
-
Study in mono and bilayers of the interaction of hepatitis G virus (GBV-C/HGV) synthetic antigen E2(99-118) with cell membrane phospholipids.
Biophysical chemistry, 2004Co-Authors: Macarena Dastis, Isabel Haro, M.a. Alsina, N. Rojo, Amiya Kumar Panda, Christian MestresAbstract:The interaction of the hepatitis G synthetic peptide E2(99-118) with cell membrane phospholipids of different characteristics such as dipalmitoylphosphatidylcholine (DPPC) and Dipalmitoylphosphatidylglycerol (DPPG) was studied by Langmuir isotherms. Epifluorescence microscopy and Atomic force microscopy (AFM) was also used to study interactions with DPPC. Compression isotherms of DPPC/E2(99-118) and DPPG/E2(99-118) mixed monolayers showed negative deviation from ideallity consistent with the existence of attractive interactions. The incorporation of the peptide in DPPC monolayer was also confirmed in epifluorescence microscopy and AFM studies. The peptide retarded the formation of DPPC domains and did not let the phospholipid get organized. No important differences in the interactions with DPPC (neutral) or DPPG (anionic) were found, thus suggesting that electrostatics forces do not have a predominant influence in these interactions.
-
Hepatitis A Synthetic Peptide VP3(110–121) Miscibility with Dipalmitoylphosphatidylcholine, Dipalmitoylphosphatidylglycerol, and Stearylamine Monolayers
Journal of colloid and interface science, 2000Co-Authors: P. Sospedra, Isabel Haro, Fermin Reig, M.a. Alsina, Marta Espina, Christian MestresAbstract:Abstract To prepare liposomes containing a synthetic hepatitis A virus antigen (HAV) [VP3(110–121)] as a vaccine, the miscibility of this peptide (with negative net charge) with a neutral lipid [dipalmitoylphosphatidylcholine (DPPC)], a negatively charged lipid [Dipalmitoylphosphatidylglycerol (DPPG)], and a positively charged lipid [Stearylamine (SA)] was studied through compression isotherms of monolayers. Mixtures with DPPC and SA showed a low degree of interaction with the peptide, the composition of the monolayer being stable through compression. For DPPG-containing monolayers larger positive deviations from ideality were found, and the peptide was squeezed out from the monolayer at a DPPG/VP3(110–121) mole fraction of 0.8/0.2. All this suggests that besides hydrophobic interactions between the peptide and the lipid, electrostatic forces also play a role; thus it seems that neutral and positively charged lipids would be more suitable for preparing stable liposomes with VP3(110–121).
-
hepatitis a synthetic peptide vp3 110 121 miscibility with dipalmitoylphosphatidylcholine Dipalmitoylphosphatidylglycerol and stearylamine monolayers
Joint International Conference on Information Sciences, 2000Co-Authors: P. Sospedra, Fermin Reig, M.a. Alsina, Marta Espina, I Haro, Christian MestresAbstract:Abstract To prepare liposomes containing a synthetic hepatitis A virus antigen (HAV) [VP3(110–121)] as a vaccine, the miscibility of this peptide (with negative net charge) with a neutral lipid [dipalmitoylphosphatidylcholine (DPPC)], a negatively charged lipid [Dipalmitoylphosphatidylglycerol (DPPG)], and a positively charged lipid [Stearylamine (SA)] was studied through compression isotherms of monolayers. Mixtures with DPPC and SA showed a low degree of interaction with the peptide, the composition of the monolayer being stable through compression. For DPPG-containing monolayers larger positive deviations from ideality were found, and the peptide was squeezed out from the monolayer at a DPPG/VP3(110–121) mole fraction of 0.8/0.2. All this suggests that besides hydrophobic interactions between the peptide and the lipid, electrostatic forces also play a role; thus it seems that neutral and positively charged lipids would be more suitable for preparing stable liposomes with VP3(110–121).
-
Influence of Phospholipidic Charge on the Interaction of a Multiple Antigenic Peptide from Hepatitis A Virus with Monolayers and Bilayers
Langmuir, 1997Co-Authors: Christian Mestres, Isabel Haro, Fermin Reig, A. Ortiz, Marco A AlsinaAbstract:Miscibility of dipalmitoylphosphatidylcholine (DPPC) with Dipalmitoylphosphatidylglycerol (DPPG), cardiolipin (CL), and dipalmitoylphosphatidylethanolamine (DPPE) was studied using mono- and bilayers of different compositions. The influence of MAP4-VP1 peptide construct (related to hepatitis A virus protein) in mixed monolayers of the lipids above cited was determined by studying penetration kinetics and compression isotherms. Moreover, liposomes with the same composition than monolayers were saturated with sodium anilinonaphthalene sulfonate or diphenylhexatriene and incubated with MAP4-VP1; polarization values as well as transition temperatures were determined. Results in isotherm and polarization studies showed some degree of interaction between the peptide and the phospholipids assayed. DPPC/DPPG composition showed the maximum interaction followed by DPPC/CL. The interaction was not strong, suggesting that the entrapment of MAP4-VP1 in liposomes in order to increase its immunogenic activity is possible.
-
INSERTION OF MAP4-VP1 PEPTIDE INTO LIPID MONOLAYERS AND BILAYERS
Biomedical Chromatography, 1997Co-Authors: Christian Mestres, Isabel Haro, Fermin Reig, Marco A AlsinaAbstract:: Myscibility of dipalmitoylphosphatidylcholine (DPPC) with Dipalmitoylphosphatidylglycerol (DPPG), cardiolipine (CL) and dipalmitoylphosphatidylethanolamine (DPPE) was studied using monomolacular layers of different compositions. The influence of MAP4-VP1 peptide construct related to HAV protein in mixed monolayers of the above cited lipid components was determined following penetration kinetics and compression isotherms. Moreover, liposomes with the same composition as monolayers were saturated with ANS or DPH and incubated with MAP4VP1, and polarization values as well as transition temperatures were determined. In general interaction is maximum with DPPC/DPPG mono and bilayers, followed by DPPC/CL. In these systems electrostatic repulsive forces seem to play a strong role.
Fermin Reig - One of the best experts on this subject based on the ideXlab platform.
-
Hepatitis A Synthetic Peptide VP3(110–121) Miscibility with Dipalmitoylphosphatidylcholine, Dipalmitoylphosphatidylglycerol, and Stearylamine Monolayers
Journal of colloid and interface science, 2000Co-Authors: P. Sospedra, Isabel Haro, Fermin Reig, M.a. Alsina, Marta Espina, Christian MestresAbstract:Abstract To prepare liposomes containing a synthetic hepatitis A virus antigen (HAV) [VP3(110–121)] as a vaccine, the miscibility of this peptide (with negative net charge) with a neutral lipid [dipalmitoylphosphatidylcholine (DPPC)], a negatively charged lipid [Dipalmitoylphosphatidylglycerol (DPPG)], and a positively charged lipid [Stearylamine (SA)] was studied through compression isotherms of monolayers. Mixtures with DPPC and SA showed a low degree of interaction with the peptide, the composition of the monolayer being stable through compression. For DPPG-containing monolayers larger positive deviations from ideality were found, and the peptide was squeezed out from the monolayer at a DPPG/VP3(110–121) mole fraction of 0.8/0.2. All this suggests that besides hydrophobic interactions between the peptide and the lipid, electrostatic forces also play a role; thus it seems that neutral and positively charged lipids would be more suitable for preparing stable liposomes with VP3(110–121).
-
hepatitis a synthetic peptide vp3 110 121 miscibility with dipalmitoylphosphatidylcholine Dipalmitoylphosphatidylglycerol and stearylamine monolayers
Joint International Conference on Information Sciences, 2000Co-Authors: P. Sospedra, Fermin Reig, M.a. Alsina, Marta Espina, I Haro, Christian MestresAbstract:Abstract To prepare liposomes containing a synthetic hepatitis A virus antigen (HAV) [VP3(110–121)] as a vaccine, the miscibility of this peptide (with negative net charge) with a neutral lipid [dipalmitoylphosphatidylcholine (DPPC)], a negatively charged lipid [Dipalmitoylphosphatidylglycerol (DPPG)], and a positively charged lipid [Stearylamine (SA)] was studied through compression isotherms of monolayers. Mixtures with DPPC and SA showed a low degree of interaction with the peptide, the composition of the monolayer being stable through compression. For DPPG-containing monolayers larger positive deviations from ideality were found, and the peptide was squeezed out from the monolayer at a DPPG/VP3(110–121) mole fraction of 0.8/0.2. All this suggests that besides hydrophobic interactions between the peptide and the lipid, electrostatic forces also play a role; thus it seems that neutral and positively charged lipids would be more suitable for preparing stable liposomes with VP3(110–121).
-
Influence of Phospholipidic Charge on the Interaction of a Multiple Antigenic Peptide from Hepatitis A Virus with Monolayers and Bilayers
Langmuir, 1997Co-Authors: Christian Mestres, Isabel Haro, Fermin Reig, A. Ortiz, Marco A AlsinaAbstract:Miscibility of dipalmitoylphosphatidylcholine (DPPC) with Dipalmitoylphosphatidylglycerol (DPPG), cardiolipin (CL), and dipalmitoylphosphatidylethanolamine (DPPE) was studied using mono- and bilayers of different compositions. The influence of MAP4-VP1 peptide construct (related to hepatitis A virus protein) in mixed monolayers of the lipids above cited was determined by studying penetration kinetics and compression isotherms. Moreover, liposomes with the same composition than monolayers were saturated with sodium anilinonaphthalene sulfonate or diphenylhexatriene and incubated with MAP4-VP1; polarization values as well as transition temperatures were determined. Results in isotherm and polarization studies showed some degree of interaction between the peptide and the phospholipids assayed. DPPC/DPPG composition showed the maximum interaction followed by DPPC/CL. The interaction was not strong, suggesting that the entrapment of MAP4-VP1 in liposomes in order to increase its immunogenic activity is possible.
-
INSERTION OF MAP4-VP1 PEPTIDE INTO LIPID MONOLAYERS AND BILAYERS
Biomedical Chromatography, 1997Co-Authors: Christian Mestres, Isabel Haro, Fermin Reig, Marco A AlsinaAbstract:: Myscibility of dipalmitoylphosphatidylcholine (DPPC) with Dipalmitoylphosphatidylglycerol (DPPG), cardiolipine (CL) and dipalmitoylphosphatidylethanolamine (DPPE) was studied using monomolacular layers of different compositions. The influence of MAP4-VP1 peptide construct related to HAV protein in mixed monolayers of the above cited lipid components was determined following penetration kinetics and compression isotherms. Moreover, liposomes with the same composition as monolayers were saturated with ANS or DPH and incubated with MAP4VP1, and polarization values as well as transition temperatures were determined. In general interaction is maximum with DPPC/DPPG mono and bilayers, followed by DPPC/CL. In these systems electrostatic repulsive forces seem to play a strong role.
-
Interactions of the HAV-VP3 (61-78) peptide with mono- and bilayers
Langmuir, 1994Co-Authors: K. Bogdam, Isabel Haro, M.a. Alsina, I. Martin, Fermin ReigAbstract:The synthesis, on a solid support, of a Hepatitis A viral protein peptide, HAV-VP3 (61-78), is described. The interaction of the peptide with, dipalmitoylphosphatidylcholine (DPPC), Dipalmitoylphosphatidylglycerol (DPPG), dioleoylphosphatidylcholine (DOPC), and distearoylphosphatidylcholine (DSPC) has been studied, using liposomes and monomolecular layers as biomembrane models. Changes in fluidity of the bilayers induced by this peptide were determined by means of polarizable probes such as 8-anilino-1-naphthalenesulfonic acid (ANS) and 1,6-diphenyl-1,3,5-hexatriene (DPH). In this way liposomes can be used as carriers for small immunogenic peptides
M.a. Alsina - One of the best experts on this subject based on the ideXlab platform.
-
Study in mono and bilayers of the interaction of hepatitis G virus (GBV-C/HGV) synthetic antigen E2(99-118) with cell membrane phospholipids.
Biophysical chemistry, 2004Co-Authors: Macarena Dastis, Isabel Haro, M.a. Alsina, N. Rojo, Amiya Kumar Panda, Christian MestresAbstract:The interaction of the hepatitis G synthetic peptide E2(99-118) with cell membrane phospholipids of different characteristics such as dipalmitoylphosphatidylcholine (DPPC) and Dipalmitoylphosphatidylglycerol (DPPG) was studied by Langmuir isotherms. Epifluorescence microscopy and Atomic force microscopy (AFM) was also used to study interactions with DPPC. Compression isotherms of DPPC/E2(99-118) and DPPG/E2(99-118) mixed monolayers showed negative deviation from ideallity consistent with the existence of attractive interactions. The incorporation of the peptide in DPPC monolayer was also confirmed in epifluorescence microscopy and AFM studies. The peptide retarded the formation of DPPC domains and did not let the phospholipid get organized. No important differences in the interactions with DPPC (neutral) or DPPG (anionic) were found, thus suggesting that electrostatics forces do not have a predominant influence in these interactions.
-
Hepatitis A Synthetic Peptide VP3(110–121) Miscibility with Dipalmitoylphosphatidylcholine, Dipalmitoylphosphatidylglycerol, and Stearylamine Monolayers
Journal of colloid and interface science, 2000Co-Authors: P. Sospedra, Isabel Haro, Fermin Reig, M.a. Alsina, Marta Espina, Christian MestresAbstract:Abstract To prepare liposomes containing a synthetic hepatitis A virus antigen (HAV) [VP3(110–121)] as a vaccine, the miscibility of this peptide (with negative net charge) with a neutral lipid [dipalmitoylphosphatidylcholine (DPPC)], a negatively charged lipid [Dipalmitoylphosphatidylglycerol (DPPG)], and a positively charged lipid [Stearylamine (SA)] was studied through compression isotherms of monolayers. Mixtures with DPPC and SA showed a low degree of interaction with the peptide, the composition of the monolayer being stable through compression. For DPPG-containing monolayers larger positive deviations from ideality were found, and the peptide was squeezed out from the monolayer at a DPPG/VP3(110–121) mole fraction of 0.8/0.2. All this suggests that besides hydrophobic interactions between the peptide and the lipid, electrostatic forces also play a role; thus it seems that neutral and positively charged lipids would be more suitable for preparing stable liposomes with VP3(110–121).
-
hepatitis a synthetic peptide vp3 110 121 miscibility with dipalmitoylphosphatidylcholine Dipalmitoylphosphatidylglycerol and stearylamine monolayers
Joint International Conference on Information Sciences, 2000Co-Authors: P. Sospedra, Fermin Reig, M.a. Alsina, Marta Espina, I Haro, Christian MestresAbstract:Abstract To prepare liposomes containing a synthetic hepatitis A virus antigen (HAV) [VP3(110–121)] as a vaccine, the miscibility of this peptide (with negative net charge) with a neutral lipid [dipalmitoylphosphatidylcholine (DPPC)], a negatively charged lipid [Dipalmitoylphosphatidylglycerol (DPPG)], and a positively charged lipid [Stearylamine (SA)] was studied through compression isotherms of monolayers. Mixtures with DPPC and SA showed a low degree of interaction with the peptide, the composition of the monolayer being stable through compression. For DPPG-containing monolayers larger positive deviations from ideality were found, and the peptide was squeezed out from the monolayer at a DPPG/VP3(110–121) mole fraction of 0.8/0.2. All this suggests that besides hydrophobic interactions between the peptide and the lipid, electrostatic forces also play a role; thus it seems that neutral and positively charged lipids would be more suitable for preparing stable liposomes with VP3(110–121).
-
Interactions of the HAV-VP3 (61-78) peptide with mono- and bilayers
Langmuir, 1994Co-Authors: K. Bogdam, Isabel Haro, M.a. Alsina, I. Martin, Fermin ReigAbstract:The synthesis, on a solid support, of a Hepatitis A viral protein peptide, HAV-VP3 (61-78), is described. The interaction of the peptide with, dipalmitoylphosphatidylcholine (DPPC), Dipalmitoylphosphatidylglycerol (DPPG), dioleoylphosphatidylcholine (DOPC), and distearoylphosphatidylcholine (DSPC) has been studied, using liposomes and monomolecular layers as biomembrane models. Changes in fluidity of the bilayers induced by this peptide were determined by means of polarizable probes such as 8-anilino-1-naphthalenesulfonic acid (ANS) and 1,6-diphenyl-1,3,5-hexatriene (DPH). In this way liposomes can be used as carriers for small immunogenic peptides
Isabel Haro - One of the best experts on this subject based on the ideXlab platform.
-
Study in mono and bilayers of the interaction of hepatitis G virus (GBV-C/HGV) synthetic antigen E2(99-118) with cell membrane phospholipids.
Biophysical chemistry, 2004Co-Authors: Macarena Dastis, Isabel Haro, M.a. Alsina, N. Rojo, Amiya Kumar Panda, Christian MestresAbstract:The interaction of the hepatitis G synthetic peptide E2(99-118) with cell membrane phospholipids of different characteristics such as dipalmitoylphosphatidylcholine (DPPC) and Dipalmitoylphosphatidylglycerol (DPPG) was studied by Langmuir isotherms. Epifluorescence microscopy and Atomic force microscopy (AFM) was also used to study interactions with DPPC. Compression isotherms of DPPC/E2(99-118) and DPPG/E2(99-118) mixed monolayers showed negative deviation from ideallity consistent with the existence of attractive interactions. The incorporation of the peptide in DPPC monolayer was also confirmed in epifluorescence microscopy and AFM studies. The peptide retarded the formation of DPPC domains and did not let the phospholipid get organized. No important differences in the interactions with DPPC (neutral) or DPPG (anionic) were found, thus suggesting that electrostatics forces do not have a predominant influence in these interactions.
-
Hepatitis A Synthetic Peptide VP3(110–121) Miscibility with Dipalmitoylphosphatidylcholine, Dipalmitoylphosphatidylglycerol, and Stearylamine Monolayers
Journal of colloid and interface science, 2000Co-Authors: P. Sospedra, Isabel Haro, Fermin Reig, M.a. Alsina, Marta Espina, Christian MestresAbstract:Abstract To prepare liposomes containing a synthetic hepatitis A virus antigen (HAV) [VP3(110–121)] as a vaccine, the miscibility of this peptide (with negative net charge) with a neutral lipid [dipalmitoylphosphatidylcholine (DPPC)], a negatively charged lipid [Dipalmitoylphosphatidylglycerol (DPPG)], and a positively charged lipid [Stearylamine (SA)] was studied through compression isotherms of monolayers. Mixtures with DPPC and SA showed a low degree of interaction with the peptide, the composition of the monolayer being stable through compression. For DPPG-containing monolayers larger positive deviations from ideality were found, and the peptide was squeezed out from the monolayer at a DPPG/VP3(110–121) mole fraction of 0.8/0.2. All this suggests that besides hydrophobic interactions between the peptide and the lipid, electrostatic forces also play a role; thus it seems that neutral and positively charged lipids would be more suitable for preparing stable liposomes with VP3(110–121).
-
Influence of Phospholipidic Charge on the Interaction of a Multiple Antigenic Peptide from Hepatitis A Virus with Monolayers and Bilayers
Langmuir, 1997Co-Authors: Christian Mestres, Isabel Haro, Fermin Reig, A. Ortiz, Marco A AlsinaAbstract:Miscibility of dipalmitoylphosphatidylcholine (DPPC) with Dipalmitoylphosphatidylglycerol (DPPG), cardiolipin (CL), and dipalmitoylphosphatidylethanolamine (DPPE) was studied using mono- and bilayers of different compositions. The influence of MAP4-VP1 peptide construct (related to hepatitis A virus protein) in mixed monolayers of the lipids above cited was determined by studying penetration kinetics and compression isotherms. Moreover, liposomes with the same composition than monolayers were saturated with sodium anilinonaphthalene sulfonate or diphenylhexatriene and incubated with MAP4-VP1; polarization values as well as transition temperatures were determined. Results in isotherm and polarization studies showed some degree of interaction between the peptide and the phospholipids assayed. DPPC/DPPG composition showed the maximum interaction followed by DPPC/CL. The interaction was not strong, suggesting that the entrapment of MAP4-VP1 in liposomes in order to increase its immunogenic activity is possible.
-
INSERTION OF MAP4-VP1 PEPTIDE INTO LIPID MONOLAYERS AND BILAYERS
Biomedical Chromatography, 1997Co-Authors: Christian Mestres, Isabel Haro, Fermin Reig, Marco A AlsinaAbstract:: Myscibility of dipalmitoylphosphatidylcholine (DPPC) with Dipalmitoylphosphatidylglycerol (DPPG), cardiolipine (CL) and dipalmitoylphosphatidylethanolamine (DPPE) was studied using monomolacular layers of different compositions. The influence of MAP4-VP1 peptide construct related to HAV protein in mixed monolayers of the above cited lipid components was determined following penetration kinetics and compression isotherms. Moreover, liposomes with the same composition as monolayers were saturated with ANS or DPH and incubated with MAP4VP1, and polarization values as well as transition temperatures were determined. In general interaction is maximum with DPPC/DPPG mono and bilayers, followed by DPPC/CL. In these systems electrostatic repulsive forces seem to play a strong role.
-
Interactions of the HAV-VP3 (61-78) peptide with mono- and bilayers
Langmuir, 1994Co-Authors: K. Bogdam, Isabel Haro, M.a. Alsina, I. Martin, Fermin ReigAbstract:The synthesis, on a solid support, of a Hepatitis A viral protein peptide, HAV-VP3 (61-78), is described. The interaction of the peptide with, dipalmitoylphosphatidylcholine (DPPC), Dipalmitoylphosphatidylglycerol (DPPG), dioleoylphosphatidylcholine (DOPC), and distearoylphosphatidylcholine (DSPC) has been studied, using liposomes and monomolecular layers as biomembrane models. Changes in fluidity of the bilayers induced by this peptide were determined by means of polarizable probes such as 8-anilino-1-naphthalenesulfonic acid (ANS) and 1,6-diphenyl-1,3,5-hexatriene (DPH). In this way liposomes can be used as carriers for small immunogenic peptides
Georgina G Tonarelli - One of the best experts on this subject based on the ideXlab platform.
-
Interaction of Acylated and Substituted Antimicrobial Peptide Analogs with Phospholipid–Polydiacetylene Vesicles. Correlation with their Biological Properties
Chemical Biology & Drug Design, 2011Co-Authors: Alvaro Siano, Arturo Carlos Simonetta, Maria Veronica Humpola, Georgina G TonarelliAbstract:A series of peptide analogs based on region 6–22 of Plantaricin 149 sequence were synthesized. The interaction between these analogs and phospholipid–polydiacetylene vesicles was investigated to evaluate the ability of the bioassay to detect differences in the interaction of the peptides with Dipalmitoylphosphatidylglycerol and dipalmitoylphosphatidylcholine vesicles, associated with amino acid substitution and N-terminal conjugation of the sequences with short fatty acids (8 and 12 carbon atoms). Fatty acid conjugation of peptides with low antimicrobial activity resulted in lipopeptides with improved activity against strains of Staphylococcus aureus and Listeria monocytogenes. The length of the fatty acid determined the bacterial specificity, and the conjugation with n-octanoic acid yielded the most active analog (C8-CT) against Staphylococcus aureus strain (MIC: 1.0 μm) while the conjugation with n-dodecanoic acid (C12-CT) was optimal for Listeria monocytogenes strain (MIC: 2.0 μm). In contrast, the substitution of Phe by Trp had an unfavorable effect on the antimicrobial activity. Hemolysis tests and membrane interaction studies with dipalmitoylphosphatidylcholine–polydiacetylene vesicles showed that lipopeptides interact to a greater extent with both biological and biomimetic membranes. Also, a good correlation was found between antimicrobial activity against Staphylococcus aureus strain and % colorimetric response values with Dipalmitoylphosphatidylglycerol–polydiacetylene vesicles.
-
Interaction of acylated and substituted antimicrobial peptide analogs with phospholipid-polydiacetylene vesicles. Correlation with their biological properties.
Chemical biology & drug design, 2011Co-Authors: Alvaro Siano, Arturo Carlos Simonetta, Maria Veronica Humpola, María Carolina Rey, Georgina G TonarelliAbstract:A series of peptide analogs based on region 6-22 of Plantaricin 149 sequence were synthesized. The interaction between these analogs and phospholipid-polydiacetylene vesicles was investigated to evaluate the ability of the bioassay to detect differences in the interaction of the peptides with Dipalmitoylphosphatidylglycerol and dipalmitoylphosphatidylcholine vesicles, associated with amino acid substitution and N-terminal conjugation of the sequences with short fatty acids (8 and 12 carbon atoms). Fatty acid conjugation of peptides with low antimicrobial activity resulted in lipopeptides with improved activity against strains of Staphylococcus aureus and Listeria monocytogenes. The length of the fatty acid determined the bacterial specificity, and the conjugation with n-octanoic acid yielded the most active analog (C8-CT) against Staphylococcus aureus strain (MIC: 1.0 μm) while the conjugation with n-dodecanoic acid (C12-CT) was optimal for Listeria monocytogenes strain (MIC: 2.0 μm). In contrast, the substitution of Phe by Trp had an unfavorable effect on the antimicrobial activity. Hemolysis tests and membrane interaction studies with dipalmitoylphosphatidylcholine-polydiacetylene vesicles showed that lipopeptides interact to a greater extent with both biological and biomimetic membranes. Also, a good correlation was found between antimicrobial activity against Staphylococcus aureus strain and % colorimetric response values with Dipalmitoylphosphatidylglycerol-polydiacetylene vesicles.