Evaluation of Immobilized Bacteriorhodopsin’s Function by Laser Irridiation

Bacteriorhodopsin (BR) is a retinal protein that is a light-driven proton pump and has an important role in photosynthesis in archaebacterium Halobacterium salinarum. The BR molecule absorbs light and photochemical changes occur in it, and different intermediates will be produced in its photochemical cycle that some of them like P and Q intermediates have a long half-life. There have been many efforts to immobilize BR for constructing data storage devices. In this study the BR suspension-contained film has been immobilized on a polycarbonate and the effects of green and red lasers on it (in different times and temperatures) have been investigated by UV spectrophotometer method, The modified surfaces were characterized by ATR-FTIR and AFM techniques. The results show that with used condition for immobilization of BR on polycarbonate, the 0 and 1 bite that relate to BR and P, Q intermediate, are formed. The red and green lasers convert BR to O and, P or Q intermediates respectively that could be used instead of 0 and 1 bites in popular compact disks.