Biologists have identified the first organism that can produce chlorophyll but does not engage in photosynthesis.
The organism, which has been informally named corallicolid, is found in 70% of corals globally. While corallicolids have a plastid – the part of plant and algal cells where photosynthesis takes place – as well as all four plastid genes used in chlorophyll production, they do not engage in photosynthesis.
Patrick Keeling from the University of British Columbia said: “This is the second most abundant cohabitant of coral on the planet and it hasn't been seen until now.
“Having chlorophyll without photosynthesis is actually very dangerous because chlorophyll is very good at capturing energy, but without photosynthesis to release the energy slowly it is like living with a bomb in your cells.”
Corallicolids are found in the gastric cavity of corals responsible for building reefs, as well as black corals, fan corals, mushroom corals, and anemones. They are the most common apicomplexans, a group of parasite, and had previously not been studied.
Waldan Kwong, lead author of the study, said: “We don't know why these organisms are holding on to these photosynthesis genes. There's some novel biology going on here, something we haven't seen before."
The team’s research – which could help efforts to preserve coral habitats – was published in Nature.