Energy transfer from light-harvesting ketocarotenoids to the light-driven proton pump xanthorhodopsins has been previously demonstrated in two unique cases: an extreme halophilic bacterium and a terrestrial cyanobacterium. Attempts to find carotenoids that bind and transfer energy to abundant rhodopsin proton pumps from marine photoheterotrophs have thus far failed. Here we detected light energy transfer from the widespread hydroxylated carotenoids zeaxanthin and lutein to the retinal moiety of xanthorhodopsins and proteorhodopsins using functional metagenomics combined with chromophore extraction from the environment.
View Article and Find Full Text PDFThe design and preparation of new vectors to transport genetic material and increase the transfection efficiency continue being an important research line. Here, a novel biocompatible sugar-based polymer derived from D-mannitol has been synthesized to be used as a gene material nanocarrier in human (gene transfection) and microalga cells (transformation process). Its low toxicity allows its use in processes with both medical and industrial applications.
View Article and Find Full Text PDFLow stability of transgenes and high variability of their expression levels among the obtained transformants are still pending challenges in the nuclear genetic transformation of microalgae. We have generated a new multicistronic microalgal expression plasmid, called Phyco69, to make easier the large phenotypic screening usually necessary for the selection of high-expression stable clones. This plasmid contains a polylinker region (PLK) where any gene of interest () can be inserted and get linked, through a short viral self-cleaving peptide to the amino terminus of the aminoglycoside 3'-phosphotransferase (APHVIII) from , which confers resistance to the antibiotic paromomycin.
View Article and Find Full Text PDFIn recent years, there has been increasing consumer interest in carotenoids, particularly of marine sustainable origin with applications in the food, cosmeceutical, nutritional supplement and pharmaceutical industries. For instance, microalgae belonging to the genus Tetraselmis are known for their biotechnologically relevant carotenoid profile. The recently isolated marine microalgal strain Tetraselmis sp.
View Article and Find Full Text PDFGenetic manipulation shows great promise to further boost the productivity of microalgae-based compounds. However, selection of microalgal transformants depends mainly on the use of antibiotics, which have raised concerns about their potential impacts on human health and the environment. We propose the use of a synthetic phytoene desaturase-encoding gene () as a selectable marker and the bleaching herbicide norflurazon as a selective agent for the genetic transformation of microalgae.
View Article and Find Full Text PDFMajor depressive disorder (MDD) is a chronic disease whose neurological basis and pathophysiology remain poorly understood. Initially, it was proposed that genetic variations were responsible for the development of this disease. Nevertheless, several studies within the last decade have provided evidence suggesting that environmental factors play an important role in MDD pathophysiology.
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