Two Types of
Photoelectric Differential Responses of Bacteriorhodopsin and Their Mechanisms
YAO Bao-Li*, LEI Ming, WANG
Ying-Li, ZHENG Yuan
( State Key Laboratory of Transient Optics Technology, Xi’an Institute of
Optics and Precision Mechanics, the Chinese Academy of Sciences, Xi’an 710068,
China )
Abstract Based on
experimental measurement of the pulse response of the bacteriorhodopsin (BR)
film photocell, the impact response function of the device is obtained by data
fitting with MATLAB software. A simulation system is accordingly built with the
SIMULINK module. The output response signals of the BR film photocell under
different stepping incident light are calculated based on this simulation
system. It is concluded that the differential response described before (which
occurs in milliseconds to seconds, outputs a positive pulse when light is on,
and outputs a negative pulse when light is off) was not the intrinsic property
of the BR molecule， but was partially caused by the
measuring circuit. The differential response caused by the intrinsic property
of the BR molecule happened in microsecond time scale, and it produced a
negative pulse when light is on and a positive pulse when light is off. The
mechanisms of the two types of differential responses are discussed.
Key words bacteriorhodopsin；impact response；differential response；convolution；simulation
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86-29-8498711; Fax, 86-29-8498711; e-mail, [email protected]