These results were determined by sequencing bacterial and archaeal 16S rRNA phylogenetic marker genes.
Bacteria, particularly Proteobacteria, dominate these groundwaters.
Proteobacteria are a large phylum of gram-negative bacteria that have diverse metabolisms and are found within many environments.
They make up one of the largest and most versatile of phyla in the Bacteria domain.
They consist of well over 460 genera, containing chemolithotrophs, heterotrophs and phototrophs.