Chapters authored
Bioinformatics Discovery of Vertebrate Cathelicidins from the Mining of Available Genomes
Due to the worrying increase in antimicrobial resistance to conventional antibiotics, the search for alternatives is becoming increasingly important. Antimicrobial peptides (AMPs), originating from natural resources, have been recognised as a novel class of antibiotics. An advantage of peptides over antibiotics is that the resistance is more difficult to attain than for conventional antibiotics. With the increasing number of genomes sequenced and available in the public domain, one alternative methodology to obtain novel AMPs is to analyse genes and proteins from genomic databases to predict and identify amino acid sequences that share similarities and molecular features with natural bioactive antimicrobial peptides. In this chapter, we summarise some of our recent results on the production of antimicrobial peptides, particularly, how we managed to identify a family of antimicrobial peptides: cathelicidins, through bioinformatics tools, from the genomes of two lower vertebrates (a reptile and a bird) available in public databases. We hope that our preliminary investigation with these novel peptides could be useful for the design of future strategies that pursue the production of antimicrobial peptides through biotechnology.
Part of the book: Drug Discovery
Reactivity and Applications of Singlet Oxygen Molecule
Reactive oxygen species (ROS) are molecules produced in living organisms, in the environment, and in various chemical reactions. The main species include, among others, singlet oxygen (1O2), the superoxide anion radical (•O2−), the hydroxyl radical (HO•), and the hydroperoxyl radical (HOO•). In general, the reactivity of 1O2 is lower than that of HO• but even higher than that of •O2−. Singlet oxygen is the lowest energy excited state of molecular oxygen, but it is also a highly reactive species, which can initiate oxidation reactions of biomolecules such as amino acids, proteins, nucleic acids, and lipids, either by a direct reaction or by the induction of ROS. Singlet oxygen is a highly reactive electrophilic species that reacts with electron-rich molecules and is related to several types of pathologies. To inhibit the oxidation of biomolecules with this species, some substances act as antioxidants by performing a quenching effect. In this chapter, aspects such as its physicochemical properties, methods of generation and detection, as well as the reactivity of this molecule are detailed.
Part of the book: Reactive Oxygen Species