Pineau B, Dubertret G, Joyard J, Douce R
J Biol Chem. 1986 Jul 15;261(20):9210-5.
At 77 K, under excitation at 440 nm, two major fluorescence emission peaks were observed in envelope membranes from spinach chloroplasts at 636 and 680 nm. A narrow range of wavelengths around 440 nm and a wider range of wavelengths between 390 and 440 nm, respectively, were responsible for excitation of the 636 and 680 nm fluorescence emissions which, in marked contrast with thylakoid fluorescence emission, were devoid of any exciting components between 460 and 500 nm. In acetonic extract of envelope membranes, two fluorescence emission peaks were observed at 635 and 675 nm. After extraction of the acetonic solution by nonpolar solvents (petroleum ether or hexane), the 675 nm fluorescence emission was partitioned between the polar and nonpolar phases whereas the 635 nm fluorescence emission was solely recovered in the polar phase. All together, the results obtained suggest that envelope membranes contain low amounts of pigments having the absorption and fluorescence spectroscopic properties, together with the behavior in polar/nonpolar solvents, of protochlorophyllide and chlorophyllide. In addition, modulation of the level of fluorescence at 636 and 680 nm could be obtained by addition of NADPH to envelope membranes under illumination. The presence of protochlorophyllide in chloroplast envelope membranes together with its possible photoconversion into chlorophyllide could have major implication for the understanding of chlorophyll biosynthesis in mature chloroplasts.
在77K温度下，以440nm波长进行激发时，在菠菜叶绿体的包膜膜中观察到两个主要的荧光发射峰，分别位于636nm和680nm处。分别在440nm附近的窄波长范围以及390至440nm之间的较宽波长范围内，激发了636nm和680nm的荧光发射，这与类囊体荧光发射形成鲜明对比，在460至500nm之间没有任何激发成分。在包膜膜的丙酮提取物中，在635nm和675nm处观察到两个荧光发射峰。用非极性溶剂（石油醚或己烷）萃取丙酮溶液后，675nm的荧光发射在极性和非极性相中分配，而635nm的荧光发射仅在极性相中回收。总之，所得结果表明，包膜膜含有少量具有原叶绿素酸酯和叶绿素酸酯的吸收和荧光光谱特性以及在极性/非极性溶剂中行为的色素。此外，在光照下向包膜膜中添加NADPH可以调节636nm和680nm处的荧光水平。叶绿体包膜膜中原叶绿素酸酯的存在及其可能向叶绿素酸酯的光转化可能对理解成熟叶绿体中的叶绿素生物合成具有重要意义。
