Relative abundances of the major taxa present in Ca. Nha. antarcticus enrichment cultures. Metagenomes for Nha-R1 (A), Nha-Ce (B), Nha-CHl (C), and Nha-CFC (D). Quadrants show relative abundances of the major taxa identified in each enrichment metagenome. Abundances were calculated using average read depth across a set of universally distributed single-copy genes. Area of the colored sections is directly proportional to the relative abundance of each taxonomic unit. The only taxa identified in all 4 metagenomes were Ca. Nha. antarcticus (Nha-R1: 41%; Nha-Ce: 19%; Nha-CHl: 30%; Nha-CFC: 47%), Hrr. lacusprofundi (Nha-R1: 28%; Nha-Ce: 59%; Nha-CHl: 56%; Nha-CFC: 29%), and Natrinema sp. (Nha-R1: 1%; Nha-Ce: 14%; Nha-CHl: 8%; Nha-CFC: 16%).