Structure and function of photosynthetic protein explained

In Germany, an international research team has elucidated the structure and mode of action of the photosynthetic complex I. The membrane protein complex plays an important role in the electron transport processes in photosynthesis.

“The results close one of the last major knowledge gaps in the understanding of the photosynthetic electron transport pathways,” said the Dr. Marc Nowaczyk, who heads the Bochum project group, Cyanobacterial Membrane Protein Complexes.

Complex I is found in almost all living organisms. In plant cells it occurs in two variants: in mitochondria, the power plants of the cell, and in chloroplasts as part of the photosynthetic machinery. The structure and function of the mitochondrial complex I has already been well studied, while the photosynthetic complex I has been poorly understood.

Using cryo-electron microscopy, the researchers first elucidated the molecular structure of a photosynthetic complex I variant. The function also analyzed it more closely. “We were able to combine the structure with the function of the photosynthetic complex I and gain a detailed insight into the molecular basis of the electron transport processes,” said Nowaczyk.