An open-access paper in PNAS is interesting on at least two scores.
First, it illustrates how bacterial genome sequencing is becoming a routine tool: two new bacterial genomes packed into one short paper.
Second is the key thrust of the paper. They sequenced two species isolated from deep hydrothermal vents in the ocean. These bacteria are related to a number of bacteria from up here on the surface, including such pathogens as Helicobacter (stomach ulcers & cancer) and Campylobacter (food poisoning).
What is striking is that they find genes in these deep sea vents which are very, very similar to important virulence genes in the terrestial nasties. A proffered explanation is that these bacteria may engage in symbioses with eukaryotes living in the vent communities.
Oceans have long enchanted and terrified humanity. The focus for the latter has usually been big things: storms & man-eating sharks. Now we must shift some of our anxiety to the very small things which live deep in Davy Jones' locker.