Pedro Roig, Laia, Camacho, Mónica, Bonete, María-José
Regulation of ammonium assimilation in Haloferax mediterranei: Interaction between glutamine synthetase and two GlnK proteins
Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics. 2013, 1834(1): 16-23. doi:10.1016/j.bbapap.2012.10.006
URI: http://hdl.handle.net/10045/44399
DOI: 10.1016/j.bbapap.2012.10.006
ISSN: 1570-9639 (Print)
Abstract: 
GlnK proteins belong to the PII superfamily of signal transduction proteins and are involved in the regulation of nitrogen metabolism. These proteins are normally encoded in an operon together with the structural gene for the ammonium transporter AmtB. Haloferax mediterranei possesses two genes encoding for GlnK, specifically, glnK1 and glnK2. The present study marks the first investigation of PII proteins in haloarchaea, and provides evidence for the direct interaction between glutamine synthetase and both GlnK1 and GlnK2. Complex formation between glutamine synthetase and the two GlnK proteins is demonstrated with pure recombinant protein samples using in vitro activity assays, gel filtration chromatography and western blotting. This protein–protein interaction increases glutamine synthetase activity in the presence of 2-oxoglutarate. Separate experiments that were carried out with GlnK1 and GlnK2 produced equivalent results.
Keywords:GlnK, PII, Haloferax mediterranei, Nitrogen metabolism regulation, 2-oxoglutarate, Glutamine synthetase
Elsevier
info:eu-repo/semantics/article