1,354,531 research outputs found
Host defense peptides: Roles and applications
No full textEditorial of special issue on Antimicrobial Peptide
Meu Lugar na UFRGS | Mestrando no Laboratório de Pesquisa do Exercício relembra seus seis anos e meio de relação com a Esefid
No full textGabriel Tossi, aluno do mestrado de Educação Física, relata sua experiência na UFRGS, e a formação da Liga Acadêmica de Ciências do Exercício (LACIEx).1- Em plano americano, Gabriel Tossi sorri e está no Laboratório de Pesquisa do Exercício, na Escola de Educação Física, Fisioterapia e Dança da UFRGS. 2- Em plano americano, Gabriel Tossi está de braços cruzados, sorri e veste um jaleco branco, em outro laboratório. Fonte: Secretaria de Comunicação Social/UFRGS, [2024]. Coloridas
Identification and characterization of a primary antibacterial domain in CAP18, a lipopolysaccharide-binding protein from rabbit leukocytes
No full textSecondary structure prediction studies on CAP18, a lipopolysaccharide binding protein from rabbit granulocytes, identified a highly cationic, 21- residue sequence with the tendency to adopt an amphipathic α-helical conformation as observed in many antimicrobial peptides. The corresponding peptide was chemically synthesized and shown to exert a potent bactericidal activity against both Gram-negative and Gram-positive bacteria, and a rapid permeabilization of the inner membrane of Escherichia coli. Five analogues were synthesized to elucidate structure/activity relationships. It was found that helix disruption virtually eliminates antibacterial activity, while the degree of amphipathicity and the presence of an aromatic residue greatly affect the kinetics of bacterial inner membrane permeabilization
Poéticas de la otredad en la dramaturgia argentina: un estudio comparado de las regiones Patagonia y Noroeste (1983-2008)
No full textFil: Tossi, Mauricio A. Universidad de Buenos Aires. Facultad de Filosofía y Letras
Poéticas de la otredad en la dramaturgia argentina: un estudio comparado de las regiones Patagonia y Noroeste (1983-2008)
No full textFil: Tossi, Mauricio A. Universidad de Buenos Aires. Facultad de Filosofía y Letras
Poéticas de la otredad en la dramaturgia argentina: un estudio comparado de las regiones Patagonia y Noroeste (1983-2008)
No full textFil: Tossi, Mauricio A. Universidad de Buenos Aires. Facultad de Filosofía y Letras
Antimicrobial peptides as anti-infective agents in pre-post-antibiotic era?
No full textResistance to antibiotics is one of the main current threats to human health and every year multi-drug resistant bacteria are infecting millions of people worldwide, with many dying as a result. Ever since their discovery, some 40 years ago, the antimicrobial peptides (AMPs) of innate defense have been hailed as a potential alternative to conventional antibiotics due to their relatively low potential to elicit resistance. Despite continued effort by both academia and start-ups, currently there are still no antibiotics based on AMPs in use. In this study, we discuss what we know and what we do not know about these agents, and what we need to know to successfully translate discovery to application. Understanding the complex mechanics of action of these peptides is the main prerequisite for identifying and/or designing or redesigning novel molecules with potent biological activity. However, other aspects also need to be well elucidated, i.e., the (bio)synthetic processes, physiological and pathological contexts of their activity, and a quantitative understanding of how physico-chemical properties affect activity. Research groups worldwide are using biological, biophysical, and algorithmic techniques to develop models aimed at designing molecules with the necessary blend of antimicrobial potency and low toxicity. Shedding light on some open questions may contribute toward improving this process
Design and Engineering Strategies for Synthetic Antimicrobial Peptides
No full textThousands of antimicrobial peptides (AMPs) of prokaryotic, fungal, plant, or animal origin have been identified, and their potential as lead compounds for the design of novel therapeutic agents in the treatment of infection, for stimulating the immune system, or in countering septic shock has been widely recognized. Added to this is their possible use in prophylaxis of infectious diseases for animal or plant protection, for disinfection of surgical instruments or industrial surfaces, and for food preservation among other commercially important applications. Since the early eighties, AMPs have been subject to a vast number of studies aimed at understanding what determines their potency and spectrum of activities against bacterial or fungal pathogens, and at maximizing these while limiting cytotoxic activities toward host cells. Much research has also been directed toward understanding specific mechanisms of action underlying the antimicrobial activity and selectivity, to be able to redesign the peptides for optimal performance. A central theme in the mode of action of many AMPs is their dynamic interaction with biological membranes, which involves various properties of these peptides such as, among others, surface hydrophobicity and polarity, charge, structure, and induced conformational variations. These features are often intimately interconnected so that engineering peptides to independently adjust any one property in particular is not an easy task. However, solid-phase peptide synthesis allows the use of a large repertoire of nonproteinogenic amino acids that can be used in the rational design of peptides to finely tune structural and physicochemical properties and precisely probe structure–function relationships
Alpha-helical antimicrobial peptides-Using a sequence template to guide structure-activity relationship studies
No full textAn important class of cytolytic antimicrobial peptides (AMPs) assumes an amphipathic, alpha-helical conformation that permits efficient interaction with biological membranes. Host defence peptides of this type are widespread in nature, and numerous synthetic model AMPs have been derived from these or designed de novo based on their characteristics. In this review we provide an overview of the 'sequence template' approach which we have used to design potent artificial helical AMPs, to guide structure-activity relationship studies aimed at their optimization, and to help identify novel natural AMP sequences. Combining this approach with the rational use of natural and non-proteinogenic amino acid building blocks has allowed us to probe the individual effects on the peptides' activity of structural and physico-chemical parameters such as the size, propensity for helical structuring, amphipathic hydrophobicity, cationicity, and hydrophobic or polar sector characteristics. These studies furthermore provided useful insights into alternative modes of action for natural membrane-active helical peptides
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