Tales from the deep: How ctenophores use membrane elasticity to survive at 1000 bar

Ctenophores are small marine invertebrates, of which there are about 100 different species. Some members live exclusively at the surface, while others have adapted to survive the crushing pressures of the deep ocean.

The members that live exclusively at great depth ("benthic") show remarkable adaptation in the lipids that constitute their cell membranes — in hindsight, perhaps not surprising, given the sensitivity of membranes to changes in pressure. SImulations, fluorescence spectroscopy, and high pressure small-angle x-ray scattering suggest that the benthic animals have adapted their lipidomes to retain access to highly curved membrane phases at high pressure. This is achieved by a spectacularly modest change in lipid chemistry, highlighting how tiny changes in chemistry can produce drastic changes in continuum properties of membranes.