Nagashima K V, Matsuura K, Wakao N, Hiraishi A, Shimada K
Department of Biology, Tokyo Metropolitan University, Japan.
Plant Cell Physiol. 1997 Nov;38(11):1249-58. doi: 10.1093/oxfordjournals.pcp.a029112.
The nucleotide sequences of the puf operons of the Zn-bacteriochlorophyll a (Zn-BChl a)-containing photosynthetic aerobic bacteria, Acidiphilium rubrum and Acidiphilium angustum, were determined. The nucleotide sequences of the pufL and -M of Acidiphilium cryptum, Acidiphilium multivorum, and Acidiphilium organovorum were also determined. The puf operons of A. rubrum and A. angustum contained pufB, -A, -L, -M, and -C as seen in other purple bacteria with an unknown gene directly upstream of pufB. Comparing the deduced amino acid sequences of the puf genes of the Acidiphilium species with those of other purple bacteria showed that His L168, which is highly conserved in other bacteria, is replaced by a glutamic acid in the Acidiphilium species. The three-dimensional structures of the reaction centers of Blastochloris (Rhodopseudomonas) viridis and Rhodobacter sphaeroides suggest that this residue locates closely to a special pair of bacteriochlorophylls and may be involved in the stabilization and function of "Zn-BChl a". The relative content of charged amino acid residues in the L and M subunit is a little lower in A. rubrum (10% of total) than in B. viridis (12%), and the tendency is more pronounced in the cytochrome subunit: 12.5% in A. rubrum and 18.8% in B. viridis.
测定了含锌细菌叶绿素a（Zn-BChl a）的光合需氧细菌嗜酸红假单胞菌和狭叶嗜酸红假单胞菌的puf操纵子的核苷酸序列。还测定了隐秘嗜酸红假单胞菌、多嗜酸红假单胞菌和有机嗜酸红假单胞菌的pufL和 -M的核苷酸序列。嗜酸红假单胞菌和狭叶嗜酸红假单胞菌的puf操纵子包含pufB、-A、-L、-M和 -C，这与其他紫色细菌中的情况相同，在pufB的直接上游有一个未知基因。将嗜酸红假单胞菌属物种的puf基因推导的氨基酸序列与其他紫色细菌的进行比较，结果表明，在其他细菌中高度保守的组氨酸L168在嗜酸红假单胞菌属物种中被谷氨酸取代。绿硫红假单胞菌（红假单胞菌属）和球形红杆菌反应中心的三维结构表明，该残基紧邻一对特殊的细菌叶绿素，可能参与“Zn-BChl a”的稳定和功能。嗜酸红假单胞菌L和M亚基中带电荷氨基酸残基的相对含量（占总量的10%）略低于绿硫红假单胞菌（12%），在细胞色素亚基中这种趋势更为明显：嗜酸红假单胞菌中为12.5%，绿硫红假单胞菌中为18.8%。
