Diversity and prospection of South Atlantic Ocean microorganisms

Abstract

The microbial diversity of the South Atlantic Ocean is less known in comparison with the other oceans, despite the ecological and biotechnological importance of marine microorganisms. In this context, this chapter aims to review the current knowledge on microbial diversity and biotechnological potential of oceanic regions of the South Atlantic. Six different phyla were reported among the cultivated bacteria, with Proteobacteria being the most frequent. The main characteristics of biotechnological interest identified in cultivated bacteria were the production of enzymes (lipase, protease, among others) and the utilization of hydrocarbons. The potential for the production of bioactive molecules was also evident in the genomes of selected bacteria. Noncultivated bacteria were also studied by the metagenomic approach, aiming to describe the composition and distribution of pelagic, hydrothermal vents and whale-fall microbial communities. South Atlantic Ocean microbial communities are mainly composed of the phyla Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes, and Cyanobacteria, which varied vertically in the pelagic realm. The phylum Proteobacteria was also the most frequent among whale-fall microbial communities, which was dominated by sulfur-oxidizing Epsilonproteobacteria. Metagenomics was also used for the prospection of microbial enzymes adapted to the extreme conditions of the deep sea, including lipases, esterases, endoglucanases, among others. Overall, the studies reviewed demonstrated the great diversity of South Atlantic microorganisms and their yet poorly studied and explored biotechnological potential.