Brunisholz R A, Bissig I, Wagner-Huber R, Frank G, Suter F, Niederer E, Zuber H
Institut für Molekularbiologie und Biophysik, ETH-Hoenggerberg, Switzerland.
Z Naturforsch C J Biosci. 1989 May-Jun;44(5-6):407-14. doi: 10.1515/znc-1989-5-612.
The antenna complex B880 of Rp. marina has been isolated by applying ion-exchange chromatography on Whatman DE-52 resin and sucrose density centrifugation of LDAO-solubilized photosynthetic membranes. The antenna polypeptides B880-alpha and B880-beta were prepared by organic solvent extraction of extensively dialyzed and freeze-dried B880 antenna complex material or photosynthetic membranes. Gel filtration on Sephadex LH-60 and ion-exchange chromatography on Whatman DE-32 resin in the presence of organic solvents and an additional step on a C-8 reversed phase column yielded pure alpha- and beta-apoproteins. Their complete primary structures have been elucidated using automated Edman degradation and carboxypeptidase digestion. According to quantitative Edman degradation the ratio of B880-alpha and B880-beta has been determined as 1:1 in the isolated antenna complex as well as in the photosynthetic membrane. B880-alpha of Rp. marina, presumably N-formylated, consists of 52 amino acid residues and is 75, 56, 52 and 44% homologous to the corresponding core antenna polypeptides of Rs. rubrum, Rp. viridis, Rb. capsulatus and Rb. sphaeroides. In contrast, B880-beta (56 amino acid residues) is less homologous to the corresponding core beta-antenna polypeptides of the same strains (57, 51, 41 and 42%). It shows an extended N-terminal domain as compared to the B880-alpha polypeptide. Apart from the typical structural features of bacterial membrane-bound antenna polypeptides (three domain structure. His-residue in the hydrophobic stretch) the antenna polypeptides of Rp. marina are structurally related to polypeptides of core antenna complexes with strong near infrared circular dichroism signals.
通过在Whatman DE - 52树脂上进行离子交换色谱以及对LDAO增溶的光合膜进行蔗糖密度离心，分离出了滨海红假单胞菌（Rp. marina）的天线复合物B880。通过对充分透析和冻干的B880天线复合物材料或光合膜进行有机溶剂萃取，制备了天线多肽B880 - α和B880 - β。在有机溶剂存在下，在Sephadex LH - 60上进行凝胶过滤以及在Whatman DE - 32树脂上进行离子交换色谱，并在C - 8反相柱上进行额外一步操作，得到了纯的α和β脱辅基蛋白。使用自动Edman降解和羧肽酶消化阐明了它们完整的一级结构。根据定量Edman降解，在分离的天线复合物以及光合膜中，B880 - α和B880 - β的比例确定为1:1。滨海红假单胞菌的B880 - α可能是N - 甲酰化的，由52个氨基酸残基组成，与深红螺菌（Rs. rubrum）、绿色红假单胞菌（Rp. viridis）、荚膜红细菌（Rb. capsulatus）和球形红细菌（Rb. sphaeroides）相应的核心天线多肽的同源性分别为75%、56%、52%和44%。相比之下，B880 - β（56个氨基酸残基）与相同菌株相应的核心β天线多肽的同源性较低（57%、51%、41%和42%）。与B880 - α多肽相比，它显示出一个延伸的N端结构域。除了细菌膜结合天线多肽的典型结构特征（三个结构域结构，疏水区域中的His残基）外，滨海红假单胞菌的天线多肽在结构上与具有强近红外圆二色性信号的核心天线复合物多肽相关。
