Cloning and protein expression in heterologous systems are very useful tools for the study of viral proteins. In this work, an in vivo cloning strategy was applied using the yeast Saccharomyces cerevisiae, as an efficient and low-cost method to clone several cDNAs from the tilapia lake virus (TiLV). Samples of infected tilapia Oreochromis niloticus tissues were taken and used to isolate their RNA and to obtain and clone the ten viral cDNAs in a shuttle plasmid. The cloning efficiencies range from 5 to 100% but for seven of the cDNAs the values were above 40%, demonstrating the high efficiency of the method. © 2021 The Authors. Journal of the World Aquaculture Society published by Wiley Periodicals LLC on behalf of World Aquaculture Society.

The antioxidant activities of the aqueous extracts of seven wild plants were investigated, using both in vitro and in vivo assays. The former relied on the use of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and the latter, on the sensibility towards hydrogen peroxide of the yeast sod1 mutant. The studied plants were all wild, collected at the Ccamarrara hill (4000 m.a.s.l. Cusco, Peru), and of the following species: Plantago australis, Baccharis latifolia, Ageratina sternbergiana, Stevia macbridei, Ageratina cuzcoensis, Calceolaria myriophylla, and Adiantum orbignyanum. The DPPH assay demonstrated high antioxidant contents in the dry leaves of all tested plants, with AAEAC values (ascorbic acid equivalent antioxidant capacity) ranging from 20.6 to 72.7 mg/g dry leaves. The antioxidant activities were also evident in the yeast assay, which also allowed distinction between the intracellular and e...

Saccharomyces cerevisiae yeast serves as a nutritional supplement and food additive that may offer highly bioavailable iron. Several studies have demonstrated the viability of using iron-chelating oligopeptides to treat anaemia, suggesting that their production in yeast cells could advantageously provide an easy-to-use supplement. In this study, an in vivo cloning strategy was optimized to construct a semi-random plasmid library that enables the production of oligopeptides with six repetitions of Asp/Glu-Asp/Glu-Leu sequences. In these sequences, the first and second positions can include either aspartate or glutamate residues, while the third is always leucine. Additionally, several plasmids were constructed to allow the study of variants of the Arg-Glu-Glu oligopeptide, previously reported as an iron chelator. In each case, the required plasmid constructions were performed using an in ...