Typically, sequencing of metagenomes has either analysed organisms that have been cultured from environmental samples or has provided incomplete genomes of various species in the sample. Iverson et al. overcame the difficulties of assembling complete, novel genomes from environmental samples using paired-end, high-throughput sequencing and computational algorithms. From sea water, they assembled an almost complete genome for an uncultured and uncharacterized euryarchaeote that represented only 1.7% of the original metagenome sequence; this allowed inferences of its physiological and metabolic characteristics based on its gene repertoire.