Unpacking a secret of photosynthesis

Researchers at University of Stavanger have brought us one step closer to solving the fundamental question how plants build the photosynthetic machinery.

In a new research paper published in the journal PlosOne, professor Lutz Eichacker and postdoc Astrid Mork-Jansson at the Centre for organelle research (CORE), UiS, provide the proof that a protein called Lil3 which has been found earlier to be key to the process is binding chlorophyll.

In barley plants germinating in the darkness of soil, the Lil3 protein accumulates when the leaf perceives the first light and the first chlorophyll molecules are made. In contrast, plants were struggling to survive, and accumulation of chlorophyll and of the photosynthetic machinery failed, when the Lil3 gene was removed from the genome.

It appeared that binding of chlorophyll by LiL3 could be a crucial step in the development of photosynthesis.

In the work now published, the researchers cloned the Lil3 gene and synthesized the Lil3 protein in the bacterium Escherichia coli. When they isolated the Lil3 protein and incubated it in the test tube with chlorophyll, they found that Lil3 binds one molecule of chlorophyll per protein.

Follow-up research will investigate further how LiL3 uses the bound chlorophyll to promote building the photosynthetic machinery.