Environmental and Evolutionary Genomics of Microbial Algae: Power and Challenges of Metagenomics

Abstract

Metagenomics is the study of the DNA content of a community of microorganisms. With the advent of next-generation sequencing technologies, more and more metagenomes from various environments are being produced. This DNA sequence profusion has revolutionized microbiology, where many cellular-based molecular approaches are hampered by cultivation difficulties. Most metagenomes correspond to sequence data from viral and bacterial communities, though allowing many new groups to be identified, though recent technological advances are now extending the approach to microbial eukaryotes. Most metagenomic studies address the fundamental issue of species richness: the number of species and their abundance distribution across environments. However, there is much more at stake than species accountancy; there is functional gene diversity, and there is also the opportunity to test current hypotheses about ecological and evolutionary processes behind community structures and dynamics. In this chapter, we aim to review some of the methodological and conceptual challenges brought by metagenomics and point to the perspectives opened to better understand the microbial algae. © 2012 Elsevier Ltd.