Publications by authors named "Marcelo Scarduelli"
Fe protein (dinitrogenase reductase) activity is reversibly inactivated by dinitrogenase reductase ADP-ribosyltransferase (DraT) in response to an increase in the ammonium concentration or a decrease in cellular energy in Azospirillum brasilense, Rhodospirillum rubrum, and Rhodobacter capsulatus. The ADP-ribosyl is removed by the dinitrogenase reductase-activating glycohydrolase (DraG), promoting Fe protein reactivation. The signaling pathway leading to DraT activation by ammonium is still not completely understood, but the available evidence shows the involvement of direct interaction between the enzyme and the nitrogen-signaling P(II) proteins.
View Article and Find Full Text PDFProteins belonging to the P(II) family coordinate cellular nitrogen metabolism by direct interaction with a variety of enzymes, transcriptional regulators and transporters. The sensing function of P(II) relies on its ability to bind the nitrogen/carbon signalling molecule 2-oxoglutarate (2-OG). In Proteobacteria, P(II) is further subject to reversible uridylylation according to the intracellular levels of glutamine, which reflect the cellular nitrogen status.
View Article and Find Full Text PDFArticle Synopsis
- Nitrogen metabolism in bacteria and archaea is controlled by P(II) proteins, which sense nitrogen, carbon, and energy levels and regulate target proteins through interactions.
- In the bacterium Azospirillum brasilense, high ammonium levels lead to the inactivation of the nitrogenase regulator DraG by relocating it to the cell membrane, facilitated by a complex involving the P(II) protein GlnZ and the ammonia channel AmtB.
- The study reveals the crystal structure of the GlnZ-DraG complex and proposes a new interaction model that allows P(II) proteins to connect with multiple targets, providing insights into how ATP, ADP, and 2-oxoglutarate levels influence these interactions.