Petroleum hydrocarbons reach the deep-sea following natural and anthropogenic factors. The process by which they enter deep-sea microbial food webs and impact the biogeochemical cycling of carbon and other elements is unclear. Hydrostatic pressure (HP) is a distinctive parameter of the deep sea, although rarely investigated. Long-term C20/C30 hydrocarbon degradation enrichments were carried out at high pressure. Multispecies colonies from these enrichments were isolated and sequenced, yielding low-complexity microbial communities that were sequenced to produce these shotgun metagenomes.