Sorting the assorted: taxonomy, systematics and molecular phylogeny of small genera in Chlorophyta

Abstract

The production of biodiesel, pharmaceuticals, pigments, and other compounds of economic interest based in microalgae biomass have been intensively studied on the last decades. In order to assure the safe application and standardization of compounds obtained from microalgae, the correct identification of microorganisms is essential. Furthermore, the correct phylogenetic identification of algae strains allows conclusions on metabolic and physiological properties, not only to scientific problems but also to biotechnological applications. Several studies on the phylogeny of green algae revealed that morphological similarity often lead to erroneous inferences about phylogenetic proximity of a close phylogenetic relationship, demonstrating that molecular approaches are necessary. Although frequent used for biotechnology purposes, most genera of the green microalgae have not been explored regarding its phylogenetic position. Furthermore, the study of strains isolated from different locations may enhance our understanding regarding species dispersion, morphological and molecular variation, since there is a lack of molecular information of protists from several areas of the globe. The main objective of this plan is to correctly identify the molecular diversity, by using molecular markers (SSU rDNA, ITS, rbcL, and tufA) and understand the morphological and molecular variation between species of the two most diverse green algae groups, Trebouxiophyceae and Chlorophyceae, mainly those genera with recognized biotechnological use. The analyses will be conducted by accessing the Central Collection of Algal Cultures, located at the University Duisburg-Essen, allowing to study isolates from diferent geographic regions on morphological (including several type-species) and molecular characteristics. It is expected that these data may improve the systematics and help in the delimitation of species in microalgae, which is a challenging task. (AU)