Protein PII regulates both inorganic carbon and nitrate uptake and is modified by a redox signal in synechocystis PCC 6803.
In Synechocystis PCC 6803 as in other cyanobacteria, involvement of protein PII in the co-regulation of inorganic carbon and nitrogen metabolism was established based on post-translational modifications of the protein resulting from changes in the carbon/nitrogen regimes. Uptake of bicarbonate and nitrate in response to changes of the carbon and/or nitrogen regimes is altered in a PII-null mutant, indicating that both processes are under control of PII. Modulation of electron flow by addition of methyl viologen with or without duroquinol, or in a NAD(P)H dehydrogenase-deficient mutant, affects the phosphorylation level of PII. The redox state of the cells would thus act as a trigger for PII phosphorylation.
Hisbergues
M
M
Laboratoire de Chimie Bactérienne, CNRS, 31 Chemin J. Aiguier, 13402, Marseille, France.
Jeanjean
R
R
Joset
F
F
Tandeau de Marsac
N
N
Bédu
S
S
D001426:Bacterial Proteins / Q000235:genetics / Q000494:pharmacology*; D001639:Bicarbonates / Q000378:metabolism; D000458:Cyanobacteria / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D006873:Hydroquinones; D009252:NADPH Dehydrogenase / Q000172:deficiency / Q000235:genetics; D009566:Nitrates / Q000378:metabolism; D010084:Oxidation-Reduction; D051922:PII Nitrogen Regulatory Proteins; D010269:Paraquat; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism
D001426:Bacterial Proteins; D001639:Bicarbonates; D006873:Hydroquinones; D009566:Nitrates; D051922:PII Nitrogen Regulatory Proteins; C404143:PIID regulatory protein, Bacteria; D009252:NADPH Dehydrogenase; D011494:Protein Kinases; D010269:Paraquat; C016421:duroquinol