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An Overview of Parasite Diversity
Published in Eric S. Loker, Bruce V. Hofkin, Parasitology, 2023
Eric S. Loker, Bruce V. Hofkin
The estimates given above mostly apply to eukaryotes. If we do not restrict the definition of a parasite to just the eukaryotic realm, parasites also include some of the prokaryotes, which have been systematically underrepresented in calculations of global species diversity. They are small and easily overlooked, and many cannot be easily isolated and cultured. Currently there are only about 9,500 named species of prokaryotes (including both bacteria and archaea). Metagenomics, the characterization of genetic material recovered directly from a particular environment (soil, water and air) without the need to culture the organisms present, has revolutionized our understanding of biodiversity for prokaryotes, and for eukaryotes too as we will soon see. The genetic material being targeted is what is referred to as environmental DNA, or eDNA, that may be derived not only from unculturable microbes but also from decomposing organisms, shed skin or mucus, feces, hair, or other organismal products released into the environment. The study of eDNA has become a powerful new tool to study biodiversity.
Quorum Sensing and Essential Oils
Published in K. Hüsnü Can Başer, Gerhard Buchbauer, Handbook of Essential Oils, 2020
Isabel Charlotte Soede, Gerhard Buchbauer
Banu et al. (2018) tested the antibiofilm and QSI potential of Cinnamomum tamala EO from India, as well as its main compounds cinnamaldehyde and linalool, on the pathogen Vibrio parahaemolyticus, which can cause food-borne infections when consuming raw sea foods. Additionally, synergistic effects of EO together with DNase and marine bacterial DNase on preformed biofilms were investigated. eDNA (environmental DNA) is seen to be as an important component of biofilms to ensure structural integrity in V. parahaemolyticus. Enzymes like DNase can therefore weaken biofilms and, as a result, can improve the efficacy of antibacterial agents by improving biofilm penetration. The authors also tested linalool and cinnamaldehyde on their preservative efficacy in prawns infected with V. parahaemolyticus and proved them to reduce bacterial load and inhibit lipid peroxidation equal to the standard food preservative sodium benzoate. Also, SEM analysis revealed that the compounds do not damage muscle tissue of the tested prawns, which makes them a possible new food preservative.
Strategies for recombinant production of antimicrobial peptides with pharmacological potential
Published in Expert Review of Clinical Pharmacology, 2020
Kamila Botelho Sampaio de Oliveira, Michel Lopes Leite, Gisele Regina Rodrigues, Harry Morales Duque, Rosiane Andrade da Costa, Victor Albuquerque Cunha, Lorena Sousa de Loiola Costa, Nicolau Brito da Cunha, Octavio Luiz Franco, Simoni Campos Dias
NRPs are known to present activity against Gram-positive and Gram-negative bacteria [244–248], including multidrug-resistant strains [249–253] and fungi [254,255]. The heterologous expression of an NRP, similarly to ribosomal peptides, could be used as a strategy for the overproduction of a specific isoform, improving the yield of a native peptide or producing it in a host organism more suitable to large-scale growth conditions [256]. Another possibility is obtaining new molecules with specific changes in their structure through directed mutations [257] in order to reduce cytotoxicity or increase antimicrobial activity. The heterologous expression also permits access to new molecules from an uncultivable microorganism or directly from environmental DNA [258,259].