摘要
用两套具有不同时间分辨率和激发方式的测量系统对菌紫质（BR）光循环动力学进行了泵浦一探测研究。一套是单次脉冲氙灯闪光诱导样品；另一套采用重复调Q倍频YAG激光器周期性激发样品。检测光使用He－Ne激光器633um红光。用雪崩光电二极管和500MHz数字示波器进行信号检测与波形处理。实验结果表明，菌紫质光循环周期＜15ms。中间体K→L的时间常数为2μs，L→M的时间常数为50μs，在中间体K之前发现了一个可疑的成份。据此给出了菌紫质光循环在纳秒到毫秒时域的模型。
With pump-probe method, the photocycle of bacteriorhodopsin is studied in two sets of measuring systems which have different time resolution and exciting mode.One is carried out by a single shot pulse Xenon lamp inducing the purple membrane suspension sample. The other is performed by a repetitive Q -switch double frequency Nd : YAG laser periodically exciting the sample. The testing beam for the two systems is a 633 nm He-Ne laser. An avalanche photodiode is used to detect the probing light passing through the sample when pumped by the actinic light. The picked up signal is coupled into a 500 MHz digitizing oscilloscope which measures and processes the BR'S photocycle response signal. The experimental results indicate that the period of BR photocycle is less than 15 ms, the time constant from K to L is 2 μs, the relaxation time from L to M is 50 ps. A doubtable component is found occurring prior to K- Based on the measured data, a model of the bacteriorhodopsin photocycle in the time domain from nanoseeond to millisecond is proposed.
出处
《光学学报》
EI
CAS
CSCD
北大核心
1996年第7期988-992,共5页
Acta Optica Sinica
基金
瞬态光学技术国家重点实验室资助
中国科学院基础性研究九五预研基金
