Question

Some photosynthetic bacteria contain the protein bacteriorhodopsin, which absorbs light and pumps protons out of the cell directly. Briefly describe how such a cell could use bacteriorhodopsin and an H+ATPase to make ATP using light.

Answer 1

Answer:

Explanation:

Bacteriorhodopsin is one of the simplest protein from a family of a protein called opsin which is present in photosynthetic bacteria, algae and few fungi.

The bacterio-rhodopsin acts as an active light-gated proton pump which can pump the protons against their concentration gradient and then establishes concentration gradient across the membrane.

When the photosynthetic bacteria gets exposed to the light, bacteriorhodopsin pumps the proton from the cytosolic side to outside. This establishes electric motive force across the membrane which causes disequilibrium of protons.

The protons move back from the outside of the membrane to inside through H+ATPase which help allow the generation of ATP in the cell.