Iron metabolism in phytoplankton

Iron is a key element for life on Earth. It is a rare element in surface seawater, and as such many phytoplankton have evolved different pathways of iron metabolism.

The EU-funded 'Iron uptake in Chromera velia and other marine microalgae' (IRONALGAE) project aimed to study iron uptake in this microalga and compare it to other classes of phytoplankton.

To achieve this, scientists investigated the genes and proteins involved in absorbing iron-containing compounds and extracting the iron atoms. They investigated a number of other microalgae as well as diatoms.

A comparison of iron-containing compounds identified ferric ethylenediaminetetraacetic acid (EDTA) as the best iron source for growth. However, ferric citrate and ferrous ascorbate can be used to study how microalgae process iron at the molecular level.

Researchers found that among all organisms studied, iron binding on the cell surface was key, although there was no common mechanism of iron binding. Using high-throughput analysis, a number of iron-uptake proteins were identified for further study.