Transcription of the glnB and glnA genes in the photosynthetic bacterium Rhodospirillum rubrum.
The PII protein, encoded by glnB, has a central role in the control of nitrogen metabolism in nitrogen-fixing prokaryotes. The glnB gene of Rhodospirillum rubrum was isolated and sequenced. The deduced amino acid sequence had very high sequence identity to other PII proteins. The glnA gene, encoding glutamine synthetase, was located 135 bp downstream of glnB and was partially sequenced. glnB is cotranscribed with glnA from a promoter with high similarity to the sigma 54-dependent promoter consensus sequence. A putative sigma 70 promoter was also identified further upstream of glnB. Northern blotting analyses showed that in addition glnA is either transcribed from an unidentified promoter or, more likely, that the glnBA transcript is processed to give the glnA mRNA. The total level of the two transcripts was much higher in nitrogen-fixing cells than in ammonia-grown cells.
Johansson
Magnus
M
Department of Biochemistry, Arrhenius Laboratories for Natural Sciences, Stockholm University, S-10691 Stockholm, Sweden.
Nordlund
Stefan
S
Department of Biochemistry, Arrhenius Laboratories for Natural Sciences, Stockholm University, S-10691 Stockholm, Sweden.
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000235:genetics; D001483:Base Sequence; D016384:Consensus Sequence; D004268:DNA-Binding Proteins; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D005798:Genes, Bacterial; D005974:Glutamate-Ammonia Ligase / Q000096:biosynthesis* / Q000235:genetics; D008969:Molecular Sequence Data; D009586:Nitrogen Fixation / Q000235:genetics*; D009690:Nucleic Acid Conformation; D051922:PII Nitrogen Regulatory Proteins; D011401:Promoter Regions, Genetic; D051877:RNA Polymerase Sigma 54; D012323:RNA Processing, Post-Transcriptional; D012329:RNA, Bacterial / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012247:Rhodospirillum rubrum / Q000235:genetics*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D012808:Sigma Factor / Q000378:metabolism; D014158:Transcription, Genetic
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D051922:PII Nitrogen Regulatory Proteins; D012329:RNA, Bacterial; D012333:RNA, Messenger; D012808:Sigma Factor; C404143:PIID regulatory protein, Bacteria; C081775:RNA polymerase sigma 70; D012321:DNA-Directed RNA Polymerases; D051877:RNA Polymerase Sigma 54; C081173:glutamine synthetase I; D005974:Glutamate-Ammonia Ligase