PEPTÍDEOS ANTIMICROBIANOS EM ANFÍBIOS: UM ESTUDO CIENCIOMÉTRICO MULTPARÂMETRO

Abstract

The International Union for the Conservation of Nature classifies Amphibians as a priority conservation group, as they account for 40% of all endangered species in the world. They are especially affected by changes in their habitat caused by climate change, deforestation, burning areas, pollution and, to preserve this group, protecting extensions of natural habitats is essential to maintain biodiversity. Studies have shown that secretions collected between species of anurans may present antiviral, antitumor, anticancer, antimicrobial activities. The disappearance of Amphibians can carry with them thousands of molecules with potential biotechnological interest, with considerable impacts both from a biological and an economic point of view. Several techniques have been explored to obtain, identify and to characterize structural and functionally of these molecules. A search conducted in the Web of Science database between 1991 and 2018 shows that the number of articles in the area of amphibian antimicrobial peptide research has been increasing over time, with 55.7% of the papers being published as from 2011. Peptides are obtained primarily from in natura collections or through the solid phase peptide synthesis, techniques that are responsible for 85% of the publications. The purification is carried out with the use of liquid chromatography (97.9% of the papers). Structural characterization is carried out mainly by use of nuclear magnetic resonance and circular dichroism, although the work involving simulation, modeling and molecular dynamics techniques showed a constant rhythm of growth from 2011. The functional characterization of the antimicrobial peptides is carried out mainly through hemolysis tests and also with the use of microorganisms, although there are criticisms to these methods. The main microorganisms studied are those that present some danger to human health, and phytopathogens, microorganisms of ecological importance and with related to the agriculture are neglected, representing a niche to be explored. Two-thirds of the research groups come from Asia and Europe, although the Americas has the greatest diversity of animals. Since several countries have not signed and/or not ratified the Nagoya Protocol (including Brazil), there is concern about the status of conservation and possible acts of biopiracy on these natural resources, which also represent possible financial resources for the country. There is no correlation between the most studied families and the number of species in each family, nor in relation to their geographical distribution. 16.5% of the species studied worldwide are threatened with extinction, and 9.8% of the species have no information or little information. The adoption of conservation measures is necessary to avoid the extinction of these animals, important repositories of bioactive molecules.