Microbial Diversity of Sponge/Coral Microbiome

Abstract

The ocean is the largest habitat on our planet for microbes. These microorganisms play a key role in global biogeochemical cycles. Still, we are missing more detail on their phylogenetic, genomic, and metabolic diversity. Microbes play a key role in the sponge and coral biology. Sponges and corals can no longer be considered as autonomous entities but rather as holobionts. Microbes contribute to the nutrition, defense, immunity, and development of the host. Associated microbes can comprise as much as half of their tissue volume, with densities in excess of a billion cells of the sponge tissue, several orders of magnitude higher than those typical for seawater. Each of the three domains of life, i.e., Bacteria, Archaea, and Eukarya (single-celled eukaryotes: fungi and microalgae), is now known to reside within sponges and corals. This chapter focuses on domains of life that are present in sponges and corals and gives an overview of their biodiversity and significance: (1) microbes in sponge and (2) microbes in corals.