Susana A. Dias
Instituto de Medicina Molecular
Surface plasmon resonanceCytotoxicityBiophysicsVesicleDrug carrierVirologyChemistryBacterial cell structureConjugateCapsidMinimum bactericidal concentrationGram-negative bacteriaMechanism of actionSnake venomCell membraneToadfishPeptideVenomStaphylococcus aureusChitosanDrug deliveryDrugContext (language use)Antibacterial activityTachyplesinCrotalicidinToxicityProtein stabilityBiofilm matrixMembrane permeabilizationAntitumor activityLipid bilayerMembraneCell envelopeProtein structureAntimicrobialAmino acidBacteriaAntimicrobial peptidesEscherichia coliFlow cytometryBiochemistryFluorescence-lifetime imaging microscopyBiofilmSequence analysisAmphiphileComputational biologyStereochemistryDrug discoveryIntracellularBiologyMicrobiologyProtein primary structureViral envelopePharmacology
Publications 10
#1Katia Conceição (UNIFESP: Federal University of São Paulo)H-Index: 10
#2Gabrielle L de Cena (UNIFESP: Federal University of São Paulo)H-Index: 1
Last. Mônica Lopes-Ferreira (Instituto Butantan)H-Index: 7
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The emergence of bacterial resistance due to the indiscriminate use of antibiotics warrants the need for developing new bioactive agents. In this context, antimicrobial peptides are highly useful for managing resistant microbial strains. In this study, we report the isolation and characterization of peptides obtained from the venom of the toadfish Thalassophryne nattereri. These peptides were active against Gram-positive and Gram-negative bacteria and fungi. The primary amino acid sequences show...
2 CitationsSource
#1Ana Salomé VeigaH-Index: 19
#2Sandra N. PintoH-Index: 13
Last. Ana CoutinhoH-Index: 20
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#1Sandra N. Pinto (IST: Instituto Superior Técnico)H-Index: 13
#2Susana A. Dias (IMM: Instituto de Medicina Molecular)H-Index: 6
Last. Ana Salomé Veiga (IMM: Instituto de Medicina Molecular)H-Index: 19
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OBJECTIVES: To investigate the mechanism of action at the molecular level of pepR, a multifunctional peptide derived from the Dengue virus capsid protein, against Staphylococcus aureus biofilms. METHODS: Biofilm mass, metabolic activity and viability were quantified using conventional microbiology techniques, while fluorescence imaging methods, including a real-time calcein release assay, were employed to investigate the kinetics of pepR activity at different biofilm depths. RESULTS: Using flow ...
7 CitationsSource
#1Felicitas Vernen (UQ: University of Queensland)H-Index: 2
#2Peta J. Harvey (UQ: University of Queensland)H-Index: 23
Last. Sónia Troeira Henriques (UQ: University of Queensland)H-Index: 31
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Tachyplesin I, II and III are host defense peptides from horseshoe crab species with antimicrobial and anticancer activities. They have an amphipathic β-hairpin structure, are highly positively-charged and differ by only one or two amino acid residues. In this study, we compared the structure and activity of the three tachyplesin peptides alongside their backbone cyclized analogues. We assessed the peptide structures using nuclear magnetic resonance (NMR) spectroscopy, then compared the activity...
9 CitationsSource
#1Clara Pérez-Peinado (Barcelona Biomedical Research Park)H-Index: 6
#2Susana A. Dias (IMM: Instituto de Medicina Molecular)H-Index: 6
Last. David Andreu (Barcelona Biomedical Research Park)H-Index: 70
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: Ctn[15-34], a downsized version of the snake venom cathelicidin-like peptide crotalicidin (Ctn), shows an unusually high lifespan (t1/2 , approximately 12 h) in human serum, which significantly adds to its promise as an antimicrobial and antitumor agent. Herein we investigate the role of Ctn[15-34] structure on serum survival. Using a set of analogs, we show that C-terminal amidation, as well as the specific layout of the Ctn[15-34] sequence-a helical N-terminal domain followed by a hydrophobi...
6 CitationsSource
Antimicrobial peptides appear among innovative biopolymers with potential therapeutic interest. Nevertheless, issues concerning efficiency, production costs, and toxicity persist. Herein, we show that conjugation of peptides with chitosans can represent an alternative in the search for these needs. To increase solubility, deacetylated and degraded chitosans were prepared. Then, they were functionalized via N-succinimidyl-S-acetylthiopropionate or via glutathione (GSH), an endogenous peptide link...
14 CitationsSource
#1Clara Pérez-Peinado (Barcelona Biomedical Research Park)H-Index: 6
#2Susana A. Dias (IMM: Instituto de Medicina Molecular)H-Index: 6
Last. David Andreu (Barcelona Biomedical Research Park)H-Index: 70
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Crotalicidin (Ctn), a cathelicidin-related peptide from the venom of a South American rattlesnake, possesses potent antimicrobial, antitumor, and antifungal properties. Previously, we have shown that its C-terminal fragment, Ctn[15-34], retains the antimicrobial and antitumor activities, but is less toxic to healthy cells and has improved serum stability. Here, we investigated the mechanism of action of Ctn and Ctn[15-34] against gram-negative bacteria. Both peptides were bactericidal, killing ~...
36 CitationsSource
#1Susana A. Dias (IMM: Instituto de Medicina Molecular)H-Index: 6
#2João M. Freire (IMM: Instituto de Medicina Molecular)H-Index: 15
Last. Ana Salomé Veiga (IMM: Instituto de Medicina Molecular)H-Index: 19
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The increasing prevalence of multidrug-resistant bacteria urges the development of new antibacterial agents. With a broad spectrum activity, antimicrobial peptides have been considered potential antibacterial drug leads. Using bioinformatic tools we have previously shown that viral structural proteins are a rich source for new bioactive peptide sequences, namely antimicrobial and cell-penetrating peptides. Here, we test the efficacy and mechanism of action of the most promising peptides among th...
19 CitationsSource
#1João M. Freire (IMM: Instituto de Medicina Molecular)H-Index: 15
#2Susana A. Dias (IMM: Instituto de Medicina Molecular)H-Index: 6
Last. Miguel A. R. B. Castanho (IMM: Instituto de Medicina Molecular)H-Index: 49
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Motivation: The need for more effective and safer pharmaceuticals is a persistent quest. Microbial adaptations create the need to permanently develop new antimicrobials (AMPs), for instance. Similarly, intracellular delivery of drugs is still a challenge and translocation of membranes for drug delivery is an area of intense research. Peptides can be used both as AMP drug leads and drug carrier systems for intracellular delivery. Multifunctional proteins are abundant in viruses but, surprisingly,...
21 CitationsSource