Question

What chloroplast protein is the functional counterpart of mitochondrial cytochrome c?

Short answer

Cytochrome $\mathrm{b}6\mathrm{f}$of chloroplast is the functional counterpart of mitochondrial cytochrome $\mathrm{c}$.

Step-by-step solution

Introduction to cytochrome  c

Cytochrome$\mathbf{c}$is a hem protein that transmits electrons between complex III and complex IV of the respiratory chain. It is found in the compartment between the inner and outer mitochondrial membranes.

The functional counterpart of mitochondrial cytochrome c

Mitochondrial proteins are important in mitochondrial function, including electron transport chain reactions.

The cytochrome $\mathbf{c}$present in the mitochondrial membrane and cytochromecomplex present in the thylakoid membrane (chloroplast) have sequence homology and structural similarities.

In the photosynthesis process, the cytochrome $\mathrm{b}6\mathrm{f}$ complex is involved in electron transport via the membranes of the thylakoids.