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Righetto GM, Lopes JLDS, Bispo PJM, André C, Souza JM, Andricopulo AD, Beltramini LM, Camargo ILBDC. Antimicrobial Activity of an Fmoc-Plantaricin 149 Derivative Peptide against Multidrug-Resistant Bacteria. Antibiotics (Basel) 2023; 12:antibiotics12020391. [PMID: 36830301 PMCID: PMC9952790 DOI: 10.3390/antibiotics12020391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 02/07/2023] [Accepted: 02/09/2023] [Indexed: 02/17/2023] Open
Abstract
Antimicrobial resistance poses a major threat to public health. Given the paucity of novel antimicrobials to treat resistant infections, the emergence of multidrug-resistant bacteria renewed interest in antimicrobial peptides as potential therapeutics. This study designed a new analog of the antimicrobial peptide Plantaricin 149 (Pln149-PEP20) based on previous Fmoc-peptides. The minimal inhibitory concentrations of Pln149-PEP20 were determined for 60 bacteria of different species and resistance profiles, ranging from 1 mg/L to 128 mg/L for Gram-positive bacteria and 16 to 512 mg/L for Gram-negative. Furthermore, Pln149-PEP20 demonstrated excellent bactericidal activity within one hour. To determine the propensity to develop resistance to Pln149-PEP20, a directed-evolution in vitro experiment was performed. Whole-genome sequencing of selected mutants with increased MICs and wild-type isolates revealed that most mutations were concentrated in genes associated with membrane metabolism, indicating the most likely target of Pln149-PEP20. Synchrotron radiation circular dichroism showed how this molecule disturbs the membranes, suggesting a carpet mode of interaction. Membrane depolarization and transmission electron microscopy assays supported these two hypotheses, although a secondary intracellular mechanism of action is possible. The molecule studied in this research has the potential to be used as a novel antimicrobial therapy, although further modifications and optimization remain possible.
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Affiliation(s)
- Gabriela Marinho Righetto
- Laboratory of Molecular Epidemiology and Microbiology, Department of Physics and Interdisciplinary Science, São Carlos Institute of Physics, University of São Paulo, São Carlos 13563-120, Brazil
| | - José Luiz de Souza Lopes
- Laboratory of Applied Biophysics, Department of Applied Physics, Institute of Physics, University of São Paulo, São Paulo 05315-970, Brazil
| | - Paulo José Martins Bispo
- Department of Ophthalmology, Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02115, USA
| | - Camille André
- Department of Ophthalmology, Infectious Disease Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, MA 02115, USA
| | - Julia Medeiros Souza
- Laboratory of Medicinal and Computational Chemistry, Department of Physics and Interdisciplinary Science, São Carlos Institute of Physics, University of São Paulo, São Carlos 13563-120, Brazil
| | - Adriano Defini Andricopulo
- Laboratory of Medicinal and Computational Chemistry, Department of Physics and Interdisciplinary Science, São Carlos Institute of Physics, University of São Paulo, São Carlos 13563-120, Brazil
| | - Leila Maria Beltramini
- Group of Biophysics and Structural Biology “Sérgio Mascarenhas”, Department of Physics and Interdisciplinary Science, São Carlos Institute of Physics, University of São Paulo, São Carlos 13563-120, Brazil
| | - Ilana Lopes Baratella da Cunha Camargo
- Laboratory of Molecular Epidemiology and Microbiology, Department of Physics and Interdisciplinary Science, São Carlos Institute of Physics, University of São Paulo, São Carlos 13563-120, Brazil
- Correspondence: ; Tel.: +55-(16)-3373-8654
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Lopes JLS, Gómara MJ, Haro I, Tonarelli G, Beltramini LM. Contribution of the Tyr-1 in Plantaricin149a to disrupt phospholipid model membranes. Int J Mol Sci 2013; 14:12313-28. [PMID: 23749115 PMCID: PMC3709787 DOI: 10.3390/ijms140612313] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 05/07/2013] [Accepted: 05/25/2013] [Indexed: 12/20/2022] Open
Abstract
Plantaricin149a (Pln149a) is a cationic antimicrobial peptide, which was suggested to cause membrane destabilization via the carpet mechanism. The mode of action proposed to this antimicrobial peptide describes the induction of an amphipathic α-helix from Ala7 to Lys20, while the N-terminus residues remain in a coil conformation after binding. To better investigate this assumption, the purpose of this study was to determine the contributions of the Tyr1 in Pln149a in the binding to model membranes to promote its destabilization. The Tyr to Ser substitution increased the dissociation constant (KD) of the antimicrobial peptide from the liposomes (approximately three-fold higher), and decreased the enthalpy of binding to anionic vesicles from -17.2 kcal/mol to -10.2 kcal/mol. The peptide adsorption/incorporation into the negatively charged lipid vesicles was less effective with the Tyr1 substitution and peptide Pln149a perturbed the liposome integrity more than the analog, Pln149S. Taken together, the peptide-lipid interactions that govern the Pln149a antimicrobial activity are found not only in the amphipathic helix, but also in the N-terminus residues, which take part in enthalpic contributions due to the allocation at a lipid-aqueous interface.
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Affiliation(s)
- José L. S. Lopes
- Institute of Physics of Sao Carlos, University of Sao Paulo, Av. Trabalhador Saocarlense 400, Sao Carlos, SP 13560-970, Brazil; E-Mail:
| | - Maria J. Gómara
- Institute of Advanced Chemistry of Catalonia (IQAC-CSIC), Barcelona 08034, Spain; E-Mails: (M.J.G.); (I.H.)
| | - Isabel Haro
- Institute of Advanced Chemistry of Catalonia (IQAC-CSIC), Barcelona 08034, Spain; E-Mails: (M.J.G.); (I.H.)
| | - Georgina Tonarelli
- Department of Organic Chemistry, National University of the Litoral, Santa Fe C.C.242 (3000), Argentina; E-Mail:
| | - Leila M. Beltramini
- Institute of Physics of Sao Carlos, University of Sao Paulo, Av. Trabalhador Saocarlense 400, Sao Carlos, SP 13560-970, Brazil; E-Mail:
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