The dolphin proline-rich antimicrobial peptide Tur1A inhibits protein synthesis by targeting the bacterial ribosome

Proline-rich antimicrobial peptides (PrAMPs) internalize into susceptible bacteria using specific transporters and interfere with protein synthesis and folding. To date, mammalian PrAMPs have so far only been identified in artiodactyls. Since cetaceans are co-phyletic with artiodactyls, we mined the genome of the bottlenose dolphin Tursiops truncates, leading to the identification of two PrAMPs, Tur1A and Tur1B. Tur1A, which is orthologous to the bovine PrAMP Bac7, is internalized into E. coli without damaging the membranes using the inner membrane transporters SbmA and YjiL/MdM. Furthermore, like Bac7, Tur1A also inhibits bacterial protein synthesis by binding to the ribosome and blocking the transition from the initiation to the elongation phase. By contrast, Tur1B is a poor inhibitor of protein synthesis and may utilize another mechanism of action. An X-ray structure of Tur1A bound within the ribosomal exit tunnel provides a basis to develop these peptides as novel antimicrobial agents

Poéticas de la otredad en la dramaturgia argentina: un estudio comparado de las regiones Patagonia y Noroeste (1983-2008)

Fil: 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)

Fil: Tossi, Mauricio A. Universidad de Buenos Aires. Facultad de Filosofía y Letras

LITERATURA INFANTIL: A CONTAÇÃO DE HISTÓRIAS ENQUANTO INSTRUMENTO DE APRENDIZAGEM NA CRECHE

A literatura enquanto forma de conhecimento assume um papel informativo e que abre as portas do saber, estimula o leitor, propicia conhecimento. O objetivo do artigo é: analisar como ocorre as práticas pedagógicas do professor utilizando a Literatura Infantil, e suas concepções sobre a contação de histórias ser um instrumento de ensino aprendizado. E o objetivo especifico é compreender como os autores discutem a Literatura Infantil enquanto instrumento de ensino aprendizado. O trabalho propõe conhecer um pouco da teoria sobre o genro literário contação de histórias. Os objetivos do trabalho contribuirão para responder aos questionamentos da pesquisa: Como os professores compreendem a Literatura Infantil enquanto uma ferramenta de ensino? Quais são e como ocorre a utilização dos instrumentos pedagógicos na contação de histórias? Com que propósito ocorrem a contação de histórias em sala de aula?  O lócus de pesquisa será uma creche municipal de Juara – MT., instrumento de pesquisa questionário. Abordagem da pesquisa qualitativa, sendo os professorxs sujeitos da pesquisa. O ato de ler e contar histórias para crianças proporciona a experimentação das emoções e angústias dos personagens, estimulando o desenvolvimento intelectual, relacionando o real com o imaginário, de forma que permita resolver conflitos/questões que vem sendo enfrentados no presente e no futuro. A aprendizagem e o desenvolvimento cognitivo da criança acontecem à medida que interage socialmente, possibilitando a geração de novas experiências e conhecimento, elaborando e se apropriando culturalmente. É o momento da contação de histórias na educação infantil que a criança tem a possibilidade de socializar os acontecimentos vivenciados por elas.  Palavra-chave: Estímulo/ aprendizado. Ludicidade. Autoconfiança

Design, synthesis and preliminary evaluation of peptidomimetic inhibitorsof HIV aspartic protease with an epoxyalcohol core

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Antimicrobial Peptide with a Bent Helix Motif Identified in Parasitic Flatworm Mesocestoides corti

The urgent need for antibiotic alternatives has driven the search for antimicrobial peptides (AMPs) from many different sources, yet parasite-derived AMPs remain underexplored. In this study, three novel potential AMP precursors (mesco-1, -2 and -3) were identified in the parasitic flatworm Mesocestoides corti, via a genome-wide mining approach, and the most promising one, mesco-2, was synthesized and comprehensively characterized. It showed potent broad-spectrum antibacterial activity at submicromolar range against E. coli and K. pneumoniae and low micromolar activity against A. baumannii, P. aeruginosa and S. aureus. Mechanistic studies indicated a membrane-related mechanism of action, and circular dichroism spectroscopy confirmed that mesco-2 is unstructured in water but forms stable helical structures on contact with anionic model membranes, indicating strong interactions and helix stacking. It is, however, unaffected by neutral membranes, suggesting selective antimicrobial activity. Structure prediction combined with molecular dynamics simulations suggested that mesco-2 adopts an unusual bent helix conformation with the N-terminal sequence, when bound to anionic membranes, driven by a central GRGIGRG motif. This study highlights mesco-2 as a promising antibacterial agent and emphasizes the importance of structural motifs in modulating AMP function

Cathelicidin-like Helminth Defence Molecules (HDMs) Absence of Cytotoxic, Anti-microbial and Anti-protozoan Activities Imply a Specific Adaptation to Immune Modulation

Host defence peptides (HDPs) are expressed throughout the animal and plant kingdoms. They have multifunctional roles in the defence against infectious agents of mammals, possessing both bactericidal and immune-modulatory activities. We have identified a novel family of molecules secreted by helminth parasites (helminth defence molecules; HDMs) that exhibit similar structural and biochemical characteristics to the HDPs. Here, we have analyzed the functional activities of four HDMs derived from Schistosoma mansoni and Fasciola hepatica and compared them to human, mouse, bovine and sheep HDPs. Unlike the mammalian HDPs the helminth-derived HDMs show no antimicrobial activity and are non-cytotoxic to mammalian cells (macrophages and red blood cells). However, both the mammalian- and helminth-derived peptides suppress the activation of macrophages by microbial stimuli and alter the response of B cells to cytokine stimulation. Therefore, we hypothesise that HDMs represent a novel family of HDPs that evolved to regulate the immune responses of their mammalian hosts by retaining potent immune modulatory properties without causing deleterious cytotoxic effects. © 2013 Thivierge et al

Present Status and Perspectives of Graphene and Graphene-related Materials in Cultural Heritage

Cultural heritage faces recurring degradation processes and natural aging phenomena, demanding the envisioning of innovative preservation solutions inspired by cutting-edge scientific research. Over extended time frames, current preservation strategies often prove inadequate in preserving the different constituent materials of cultural assets, which are thus threatened by their inherent fragility and by the complex interactions with the surrounding environment. The distinctive properties of graphene and graphene-related materials (GRMs) now offer unexplored opportunities in the field of cultural heritage, addressing various forms of deterioration phenomena. This work critically analyzes early-stage literature on the use of graphene and GRMs. Strengths, weaknesses, and limitations in anti-corrosion, anti-fading, and consolidation properties of graphene and GRMs are thoroughly investigated, along with their possible applications in smart sensors to monitor the state of health of endangered artifacts. The aim is to elucidate how specific characteristics of graphene and GRMs can be applied to the conservation, diagnostics, and monitoring of artistic and archaeological assets. Future perspectives in the design of stable, long-lasting, and compatible graphene-based solutions for cultural heritage protection are highlighted, providing a detailed discussion on potentials and pitfalls.The conservation and restoration of cultural heritage necessitates unprecedented solutions against natural aging and degradation. Graphene and graphene-related materials (GRMs) have unique characteristics and properties and could provide novel opportunities. This review aims to elucidate how specific characteristics of these materials can be applied to the conservation, diagnostics, and monitoring of artistic and archeological assets.imag

UV-B alleviates postharvest chilling injury of zucchini fruit associated with a reduction in oxidative stress

Cold storage is widely used to preserve the physical and chemical qualities of fresh fruit and vegetables. However, some tropical and subtropical fruit are very sensitive to cold, exhibiting external and internal chilling injury (CI) symptoms when stored at low temperatures. In this study, we analyze the effect of UV-B irradiation on chilling injury and oxidative stress of zucchini fruit (Cucurbita pepo) from three hybrid cultivars that differ in their sensitivity to CI. Fruit with an average length of 20 cm was irradiated with 1.1 W m−2 of UV-B for 4 hours before storage for 7 days at 4 °C. The fruit of the three cultivars responded positively to UV-B, significantly reducing the CI index, weight and firmness loss, H2O2 content, and membrane damage during cold storage. The fruit exposed to UV-B also exhibited higher levels of flavonoid content and antioxidant capacity, which correlated with a significant reduction in cold damage between cultivars and treatments. The expression of CpNCED1, a key gene in the ABA biosynthesis pathway, increased in response to cold stress and UV-B treatment, suggesting that ABA could mediate the response to UV-B. Taken together, the results indicate that postharvest UV-B irradiation of zucchini fruit enhances chilling tolerance by triggering an increase in flavonoid accumulation and antioxidant capacity, and therefore reducing the oxidative stress generated during fruit storage at low temperature.Fil: Tossi, Vanesa Eleonora. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentina. Universidad de Almería; EspañaFil: Regalado, Jose J.. Universidad de Almería; EspañaFil: Martínez, J.. Universidad de Almería; EspañaFil: Galván, A.. Universidad de Almería; EspañaFil: Martínez Tosar, Leandro Julián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; ArgentinaFil: Pitta Alvarez, Sandra Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; ArgentinaFil: Rebolloso, M. M.. Universidad de Almería; EspañaFil: Jamilena, M.. Universidad de Almería; Españ

DAMPD: a manually curated antimicrobial peptide database

The demand for antimicrobial peptides (AMPs) is rising because of the increased occurrence of pathogens that are tolerant or resistant to conventional antibiotics. Since naturally occurring AMPs could serve as templates for the development of new anti-infectious agents to which pathogens are not resistant, a resource that contains relevant information on AMP is of great interest. To that extent, we developed the Dragon Antimicrobial Peptide Database (DAMPD, http://apps.sanbi.ac.za/dampd) that contains 1232 manually curated AMPs. DAMPD is an update and a replacement of the ANTIMIC database. In DAMPD an integrated interface allows in a simple fashion querying based on taxonomy, species, AMP family, citation, keywords and a combination of search terms and fields (Advanced Search). A number of tools such as Blast, ClustalW, HMMER, Hydrocalculator, SignalP, AMP predictor, as well as a number of other resources that provide additional information about the results are also provided and integrated into DAMPD to augment biological analysis of AMPs