CLAYTON R K
J Gen Physiol. 1965 Mar;48(4):633-46. doi: 10.1085/jgp.48.4.633.
Green photosynthetic bacteria exhibit variations in the intensity of their fluorescence during illumination. The initial intensity of fluorescence, measured at the onset of illumination, has a spectrum in which the major pigment Chlorobium chlorophyll predominates. The minor pigment bacteriochlorophyll predominates in the spectrum of the time-varying part of the fluorescence. The spectrum of delayed light emission is identical to that of the time-varying fluorescence. The variations in fluorescence also resemble the delayed light in their kinetics and in their dependence on exciting light intensity. Similar results are obtained for the kinetics of prompt and delayed light emission in the algae Chlorella and Anacystis. These findings raise the possibility that the variations in fluorescence actually represent a fast component of delayed light emission, of intensity comparable to the intensity of fluorescence. In Anacystis there is an outburst of light emission that develops after the exciting light has been turned off, reaching a maximum intensity after 1 to 3 seconds. This emitted light has the spectrum of chlorophyll fluorescence. It appears to be a novel example of bioluminescence with singlet excited chlorophyll as the emitter.
绿色光合细菌在光照期间其荧光强度会发生变化。在光照开始时测量的初始荧光强度具有一个光谱，其中主要色素绿菌叶绿素占主导。次要色素细菌叶绿素在荧光随时间变化部分的光谱中占主导。延迟发光的光谱与随时间变化的荧光光谱相同。荧光的变化在其动力学以及对激发光强度的依赖性方面也类似于延迟光。对于小球藻和鱼腥藻中即时和延迟发光的动力学也获得了类似的结果。这些发现增加了一种可能性，即荧光的变化实际上代表了延迟发光的一个快速成分，其强度与荧光强度相当。在鱼腥藻中，在激发光关闭后会出现一次发光爆发，在1到3秒后达到最大强度。这种发射光具有叶绿素荧光的光谱。它似乎是以单重激发叶绿素作为发射体的生物发光的一个新例子。
