Carbon supply and 2-oxoglutarate effects on expression of nitrate reductase and nitrogen-regulated genes in Synechococcus sp. strain PCC 7942.
Synthesis of nitrate reductase in the unicellular cyanobacterium Synechococcus sp. strain PCC 7942 took place at a slow rate when the cells were incubated without a supply of inorganic carbon, but addition to these cells of CO(2)/bicarbonate or, in a Synechococcus strain transformed with a gene encoding a 2-oxoglutarate permease, 2-oxoglutarate stimulated expression of the enzyme. Induction by 2-oxoglutarate was also observed at the mRNA level for two nitrogen-regulated genes, nir and amt1, but not for the photosystem II D1 protein-encoding gene psbA1. Our results are consistent with a role of 2-oxoglutarate in nitrogen control in cyanobacteria.
Instituto de Bioquímica Vegetal y Fotosíntesis, CSIC-Universidad de Sevilla, Seville, Spain.
María Félix
MF
Vázquez-Bermúdez
Antonia
A
Herrero
Enrique
E
Flores
D001426:Bacterial Proteins; D002244:Carbon / Q000378:metabolism / Q000494:pharmacology*; D000458:Cyanobacteria / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D029382:Dicarboxylic Acid Transporters / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects*; D005809:Genes, Regulator; D007656:Ketoglutaric Acids / Q000494:pharmacology*; D050901:Nitrate Reductase; D009565:Nitrate Reductases / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D029382:Dicarboxylic Acid Transporters; D029968:Escherichia coli Proteins; D007656:Ketoglutaric Acids; D014157:Transcription Factors; C068628:KgtP protein, E coli; C075617:ntcA protein, Synechococcus; D002244:Carbon; D009565:Nitrate Reductases; D050901:Nitrate Reductase; D009584:Nitrogen