Neumann E M
Department of Physiology, Carlsberg Laboratory, Copenhagen Valby.
Carlsberg Res Commun. 1988;53(4):259-75. doi: 10.1007/BF02907182.
The psbA, psbD and psbC genes encoding the quinone binding D-1 and D-2 apoproteins and the 44 kD chlorophyll a-apoprotein 3 have been located in the chloroplast genome of barley. They are found on a 23 kbp SalI restriction endonuclease fragment in the large single copy region of the chloroplast DNA adjacent to the inverted repeat. As in other species the psbD and psbC genes have reading frames which overlap by 53 bp. They are transcribed in the same direction but translated with a frameshift of one nucleotide. Ten amino acid substitutions are found among the 18 N-terminal residues of the D-2 polypeptide if barley, spinach, tobacco, pea and the liverwort Marchantia are compared. Only 8 substitutions are present among the 335 other residues of the D-2 polypeptide. The amino acid residues located in the putative binding site for the special pair reaction center chlorophyll and the residues probably serving as ligands to non-heme iron in the D-1 and D-2 proteins of barley are strictly conserved when compared to those of purple bacteria and of other higher plants. Identity is also observed for the residues of importance in the binding of quinones.
编码醌结合D - 1和D - 2脱辅基蛋白以及44 kD叶绿素a -脱辅基蛋白3的psbA、psbD和psbC基因已定位在大麦的叶绿体基因组中。它们位于叶绿体DNA大单拷贝区域中与反向重复序列相邻的一个23 kbp的SalI限制性内切酶片段上。与其他物种一样，psbD和psbC基因的阅读框重叠53 bp。它们按相同方向转录，但翻译时发生一个核苷酸的移码。如果比较大麦、菠菜、烟草、豌豆和地钱Marchantia的D - 2多肽的18个N端残基，会发现其中有10个氨基酸替换。在D - 2多肽的其他335个残基中仅存在8个替换。与紫色细菌和其他高等植物相比，大麦D - 1和D - 2蛋白中位于特殊对反应中心叶绿素假定结合位点的氨基酸残基以及可能作为非血红素铁配体的残基是严格保守的。在醌结合中重要的残基也存在一致性。
