Double blocking of carbon metabolism causes a large increase of Calvin-Benson cycle compounds in cyanobacteria.

Carbon-flow-regulator A (CfrA) adapts carbon flux to nitrogen conditions in nondiazotrophic cyanobacteria. Under nitrogen deficiency, CfrA leads to the storage of excess carbon, which cannot combine with nitrogen, mainly as glycogen. cfrA overexpression from the arsenite-inducible, nitrogen-independent ParsB promoter allows analysis of the metabolic effects of CfrA accumulation.

The sRNA NsiR4 fine-tunes arginine synthesis in the cyanobacterium sp. PCC 6803 by post-transcriptional regulation of PirA.

As the only oxygenic phototrophs among prokaryotes, cyanobacteria employ intricate mechanisms to regulate common metabolic pathways. These mechanisms include small protein inhibitors exerting their function by protein-protein interaction with key metabolic enzymes and regulatory small RNAs (sRNAs). Here we show that the sRNA NsiR4, which is highly expressed under nitrogen limiting conditions, interacts with the mRNA of the recently described small protein PirA in the model strain sp.

The Novel P-Interacting Protein PirA Controls Flux into the Cyanobacterial Ornithine-Ammonia Cycle.

Among prokaryotes, cyanobacteria have an exclusive position as they perform oxygenic photosynthesis. Cyanobacteria substantially differ from other bacteria in further aspects, e.g.

CfrA, a Novel Carbon Flow Regulator, Adapts Carbon Metabolism to Nitrogen Deficiency in Cyanobacteria.

Cyanobacteria unable to fix atmospheric nitrogen have evolved sophisticated adaptations to survive to long periods of nitrogen starvation. These genetic programs are still largely unknown-as evidenced by the many proteins whose expression is regulated in response to nitrogen availability, but which belong to unknown or hypothetical categories. In sp.

Dynamics of the intrinsically disordered inhibitor IF7 of glutamine synthetase in isolation and in complex with its partner.

Glutamine synthetase (GS) catalyzes the ATP-dependent formation of glutamine from glutamate and ammonia. The activity of Synechocystis sp. PCC 6803 GS is regulated, among other mechanisms, by protein-protein interactions with a 65-residue-long, intrinsically disordered protein (IDP), named IF7.