Rubio L M, Herrero A, Flores E
Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Spain.
Plant Mol Biol. 1996 Feb;30(4):845-50. doi: 10.1007/BF00019017.
The narB gene from the cyanobacterium Synechococcus sp. PCC 7942 was cloned downstream from the LacI-regulated promoter Ptrc in the Escherichia coli vector pTrc99A, rendering plasmid pCSLM1. Addition of isopropyl-beta-D-thiogalactoside to E. coli (pCSLM1) resulted in the parallel expression of a 76 kDa polypeptide and a nitrate reductase activity with properties identical to those known for nitrate reductase isolated from Synechococcus cells. As is the case for nitrate reductase from Synechococcus cells, either reduced methyl viologen or reduced ferredoxin could be used as an electron donor for the reduction of nitrate catalyzed by E. coli (pCSLM1) extracts. This data shows that narB is a cyanobacterial structural gene for nitrate reductase.
来自蓝藻聚球藻属（Synechococcus sp.）PCC 7942的narB基因被克隆到大肠杆菌载体pTrc99A中LacI调控的启动子Ptrc的下游，构建成质粒pCSLM1。向大肠杆菌（pCSLM1）中添加异丙基-β-D-硫代半乳糖苷会导致一种76 kDa多肽的平行表达以及一种硝酸还原酶活性，其性质与从聚球藻细胞中分离出的硝酸还原酶已知的性质相同。与聚球藻细胞中的硝酸还原酶情况一样，无论是还原型甲基紫精还是还原型铁氧还蛋白都可以用作大肠杆菌（pCSLM1）提取物催化硝酸还原的电子供体。该数据表明narB是硝酸还原酶的蓝藻结构基因。
