Meyer M, Scheer H, Breton J
Botanisches Institut der Universität München, Germany.
FEBS Lett. 1996 Sep 9;393(1):131-4. doi: 10.1016/0014-5793(96)00869-1.
Site-specific pigment modifications are useful to investigate structure-function relationships in photosynthesis. In reaction centers bearing modified (bacterio)pheophytins, changed electron transfer kinetics have been related to the changed redox potentials of the pigments introduced (Huber, H. et al. (1995) Chemical Physics, Special Issue, vol 197 (Hochstrasser, R.M. and Hofacker, G.L. eds.) pp. 297-305; [1]). In order to analyze potentially interfering structural changes induced in these reaction centers by the exchange procedure, in particular mispositioning or misorientation of the pigments, low-temperature linear dichroism spectra have been measured for reaction centers from Rhodobacter sphaeroides containing modified bacteriopheophytins and bacteriochlorophylls at the sites HA,B and BA,B, respectively. They show that all modified pigments are oriented similar to the native ones, and that they do not affect significantly the linear dichroism of the monomeric bacteriocholorophylls and bacteriopheophytins or of the primary donor.
位点特异性色素修饰有助于研究光合作用中的结构-功能关系。在带有修饰（细菌）脱镁叶绿素的反应中心中，电子转移动力学的改变与引入色素的氧化还原电位变化有关（Huber, H.等人，(1995)《化学物理》，特刊，第197卷（Hochstrasser, R.M.和Hofacker, G.L.编），第297 - 305页；[1]）。为了分析在这些反应中心中由交换过程引起的潜在干扰结构变化，特别是色素的错位或取向错误，分别对球形红杆菌反应中心在HA,B和BA,B位点含有修饰细菌脱镁叶绿素和细菌叶绿素的情况进行了低温线性二色性光谱测量。结果表明，所有修饰色素的取向与天然色素相似，并且它们不会显著影响单体细菌叶绿素、细菌脱镁叶绿素或初级供体的线性二色性。
