A cyanobacterialnarBgene encodes a ferredoxin-dependent nitrate reductase

✍ Scribed by Luis M. Rubio; Antonia Herrero; Enrique Flores

• Book ID: 104615132
• Publisher: Springer
• Year: 1996
• Tongue: English
• Weight: 491 KB
• Volume: 30
• Category: Article
• ISSN: 0167-4412
• DOI: 10.1007/bf00019017

✦ Synopsis

The narB gene from the cyanobacterium Synechococcus sp. PCC 7942 was cloned downstream from the LacI-regulated promoter P,rc in the Escherichia coli vector pTrc99A, rendering plasmid p C S L M 1. Addition of isopropyl-~-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.