Rhiel E, Stirewalt V L, Gasparich G E, Bryant D A
Department of Molecular and Cell Biology, Pennsylvania State University, University Park 16802.
Gene. 1992 Mar 1;112(1):123-8. doi: 10.1016/0378-1119(92)90313-e.
The psaC genes of the cyanobacterium, Synechococcus sp. PCC7002, and of the cyanelle genome of the phylogenetically ambiguous biflagellate, Cyanophora paradoxa, were cloned, mapped and sequenced. The PsaC proteins of both species exhibit high degrees (approx. 95%) of sequence similarity to the PsaC proteins of other cyanobacteria as well as the chloroplast-encoded proteins of green algae and higher plants. The Synechococcus sp. PCC7002 psaC gene is transcribed as a monocistronic mRNA of approx. 350-400 nt, and transcription is initiated 51 nt upstream from the translational start codon. As found for the chloroplasts of higher plants, the C. paradoxa psaC gene is encoded within the small single-copy region of the cyanelle genome. In contrast to results obtained for chloroplasts and for the cyanobacterium Synechocystis sp. PCC6803, neither psaC gene is flanked by genes encoding components of the NAD(P)H dehydrogenase complex.
对蓝细菌聚球藻属（Synechococcus sp.）PCC7002以及系统发育地位不明的双鞭毛生物蓝载色体藻（Cyanophora paradoxa）的蓝载色体基因组中的psaC基因进行了克隆、定位和测序。这两个物种的PsaC蛋白与其他蓝细菌的PsaC蛋白以及绿藻和高等植物叶绿体编码的蛋白均表现出高度的序列相似性（约95%）。聚球藻属PCC7002的psaC基因转录为约350 - 400 nt的单顺反子mRNA，转录起始于翻译起始密码子上游51 nt处。正如在高等植物叶绿体中所发现的那样，蓝载色体藻的psaC基因位于蓝载色体基因组的小单拷贝区域内。与叶绿体以及蓝细菌聚球藻属PCC6803的结果相反，这两个psaC基因两侧均没有编码NAD(P)H脱氢酶复合体组分的基因。
