TY - JOUR T1 - Low-temperature retinal photoisomerization dynamics in bacteriorhodopsin JF - Journal of Physical Chemistry B Y1 - 1998 A1 - Logunov, Stephan L. A1 - Masciangioli, Tina M. A1 - Kamalov, Valey F. A1 - El-Sayed, Mostafa A AB - Retinal photoisomerization dynamics are studied at both room temperature and 20 K in wild-type bacteriorhodopsin using femtosecond pulses. We were able to resolve the decay at 20 K into two components with the dominant component having a similar lifetime to that observed at room temperature. This strongly suggests that the retinal lifetime at physiological temperature is barrierless. The minor, low-temperature long-lived component is discussed in terms of previous results obtained for fluorescence and transient absorption with lower time resolution, and the origin of this component is discussed in terms of low-temperature glass heterogeneity. VL - 102 SN - 1089-5647 N1 - Logunov, SL Masciangioli, TM Kamalov, VF El-Sayed, MA M3 - 10.1021/jp972921a ER -