ABSTRACT

The metagenomics of marine ecosystems is one of intriguing areas of marine ecological studies. The marine environment is extremely diverse and constitutes the largest habitat, as it covers more than 70% of the Earth’s surface and dominated by the microbial community members, namely, archaea, bacteria, and eukarya, in both abundance and diversity (Azam and Malfatti, 2007). The entire ocean is known to consist of millions of species and a single microliter of it is estimated to harbor thousands of different bacteria and archaea (Curtis et al., 2002). Bacteria represent a major portion of the Earth’s biota with a number of microbial cells, estimated to be more than 1030 (Whitman et al., 1998). These bacteria operate as highly interdependent communities, which is fundamental to ecosystem functioning and sustainability. The bacterial communes act as a driver in different processes, such as primary production, organic matter remineralization, pollution remediation, and global biogeochemical cycling of the key elements including carbon, nitrogen, and sulfur (Falkowski et al., 2008). Microbes are the foundation of the biosphere, as they play a crucial role in biotechnology (Curtis et al., 2003), agriculture (Kennedy and Smith, 1995), environment (Xu et al., 2010), and human health (Ley et al., 2006).