Armed in ... a drop of water

Some seas have very few organisms, which at first glance look like 'saltwater desert' but when carefully studied there are surprisingly high concentrations of microorganisms.

Prochlorococcus bacteria have the ability to self-mutate to fight 'foreign invasion' virus - Photo: Proportal.mit.edu

According to the Nature journal, the first 50 meters below the ocean surface, each liter of seawater has about 100 billion ' crowded ' viruses. How can other microorganisms (bacteria, unicellular organisms .) exist before aggressive parasites, 10 times bigger than me? The answer comes from scientists at the Technion Institute (Israel): they have to ' armed themselves' by changing some genetic information.

According to research on Prochlorococcus , a photosynthetic spherical bacterium (cyanobacteria) lives in tropical and subtropical oceans. When attacked, Prochlorococcus will mutate a gene by itself, hindering its ability to attach to the host cell's shell. This strategy proved to be very effective, but also caused some 'troubles ' because mutated prochlorococcus will reproduce more slowly and also be more vulnerable to other parasites.

Unsurprisingly, the virus also makes mutations to enhance more modern ' weapons ', helping them re-enter the well-defended Prochlorococcus hosts. In the ' arms race ' in a drop of water, the virus often attacks the most crowded bacteria. Thus, according to the time line, they help the ocean environment retain diversity in microorganism groups.