title: A cyanobacterial narB gene encodes a ferredoxin-dependent nitrate reductase.
abstract: 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.
authors.affiliation: Instituto de Bioquímica Vegetal y Fotosíntesis, Universidad de Sevilla-CSIC, Spain.
authors.forename: L M
authors.initials: LM
authors.lastname: Rubio
authors.forename: A
authors.initials: A
authors.lastname: Herrero
authors.forename: E
authors.initials: E
authors.lastname: Flores
mesh_terms: D001483:Base Sequence; D003001:Cloning, Molecular; D000458:Cyanobacteria / Q000201:enzymology / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics; D005288:Ferredoxins / Q000378:metabolism; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D050901:Nitrate Reductase; D009565:Nitrate Reductases / Q000235:genetics* / Q000378:metabolism; D009566:Nitrates / Q000378:metabolism; D010084:Oxidation-Reduction; D010269:Paraquat / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism
chemical_list: D005288:Ferredoxins; D009566:Nitrates; D011994:Recombinant Proteins; D009565:Nitrate Reductases; D050901:Nitrate Reductase; D010269:Paraquat