Absorption characteristics of bacteriorhodopsin molecules

Pramana

K Appaji Gowda¹  H K T Kumar² 

[1] Department of Physics, Bangalore University, Bangalore 560 056, India$$;Department of Physics, Siddaganga Institute of Technology, Tumkur 572 103, India$$

关键词: Slow saturable absorber;    photocycle;    two-level system;    biomolecule.;   

DOI  :  

学科分类：物理（综合）

来源: Indian Academy of Sciences

【 摘 要 】

The bacteriorhodopsin molecule absorbs light and undergoes a series of structural transformation following a well-defined photocycle. The complex photocycle is transformed to an equivalent level diagram by considering the lifetime of the intermediate states. Assuming that only 𝐵 and 𝑀 states are appreciably populated at any instant of time, the level diagram is further simplified to two-level system. Based on the rate equations for two-level system, an analytic expression for the absorption coefficient of bacteriorhodopsin molecule is derived. It is applied to study the behaviour of absorption coefficient of bacteriorhodopsin film in the visible wavelength region of 514 nm. The dependence of absorption coefficient of bacteriorhodopsin film on the thickness of the film, total number density of active molecules and initial number density of molecules in 𝐵-state is presented in the graphical form.

【 授权许可】

Unknown