Covalent modification of the glnG product, NRI, by the glnL product, NRII, regulates the transcription of the glnALG operon in Escherichia coli.

Abstract

Transcription from nitrogen-regulated pro- NRII-independent mechanism for the regulation of transcription from glnAp2 does exist.The regulation of ginA expression by NRII requires the products of two additional genes, ginD and ginB (9, 10). The ginD gene product is a uridylyltransferase (UTase) required for the conversion of PI,, the ginB gene product, to a uridylylated form, and a uridylyl-removing enzyme, which catalyzes the reverse reaction. The ability of UTase to convert PI, to PII-UMP is stimulated by 2-ketoglutarate and, conversely, the ability of uridylyl-removing enzyme to remove the uridylyl group from PII-UMP is stimulated by glutamine (11). Thus, ammonia starvation, which results in a high intracellular ratio of 2-ketoglutarate to glutamine, causes the conversion of PI, to PII-UMP. Growth

Phosphorylation-independent Dimer-Dimer Interactions by the Enhancer-binding Activator NtrC of Escherichia coli

“…In Vitro Transcription-The basic procedures have been described (39,40). All concentrations (for glnA and ast transcription) are final concentrations in the 25-l reaction.…”

Novel regulation targets of the metal-response BasS–BasR two-component system of Escherichia coli

“…Escherichia coli K-12 contains a total of approximately 300 transcription factors (Ishihama, 2009(Ishihama, , 2010, of which about 10 % are TCSs, including 30 species of the sensor kinase and 34 species of the response regulator (Nagasawa et al, 1993;Yamamoto et al, 2005). The assimilation of essential elements (K, P, N and Mg) is under the control of the KdpDE (Asha & Gowrishankar, 1993), PhoRB (Wanner & Chang, 1987), GlnLG (or NtrBC) (Ninfa & Magasanik, 1986) and PhoQP (Kato et al, 1999) TCS pairs, respectively, while BasSR (Fe, Zn), CusSR (Cu), CpxAR (Cu) and ZraSR (Zn) TCSs are involved in the E. coli response to essential but toxic divalent metals (Yamamoto et al, 2005;Yamamoto & Ishihama, 2005a, b, 2006. Microarray analysis indicated that the E. coli BasSR system controls, directly or indirectly, a set of genes that are associated with metal-response membrane modification, and genes for response to acidic and/or anaerobic growth conditions (Hagiwara et al, 2004;Lee et al, 2005).…”

Escherichia coli PII protein: purification, crystallization and oligomeric structure

“…When the level of nitrogen is high (> 1 mM NH,), P,, acts with adenylyl transferase (product of gZnE) to covalently modify glutamine synthetase subunits to progressively inactivate the dodecameric enzyme. At high concentrations of NH,, P,, also lowers the level of glutamine synthesis by repressing expression of the glnALG operon mediated by the regulatory proteins NR,, and NR, (products of glnL and gZnG, respectively) [3]. When the level of nitrogen is low (< 1 mM NHJ P,, is uridylylated at tyrosine-51 to form P,,-UMP [4].…”