Characteristics of fluorescamine modified bacteriorhodopsin.

The light activated proton pump, bacteriorhodopsin was modified with varying amounts of flourescamine, the fluorescamine to protein ratio ranging from 1 to 100. The modified protein was washed free of excess of fluorescamine and reconstituted into phospholipid vesicles to check the proton pumping activity. Although the spectral investigations indicated chemical modification, the circular dichroism measurements pointed to an overall loss of the trimeric structure of the protein. The implications of the present study are that the modifying agent can interact non-specifically with the protein, altering its structural parameters, which in turn affects the function of the protein.