Disease relevance of ntrC

• This extension encodes a putative DNA-binding domain strongly homologous to the Rhizobium meliloti nifA protein and to some extent to the ntrC protein [1].
• Sequence and domain relationships of ntrC and nifA from Klebsiella pneumoniae: homologies to other regulatory proteins [1].
• Similar to its counterparts in K. pneumoniae and Escherichia coli, R. meliloti ntrC is expressed when the cells are grown in nitrogen-limiting media [2].
• We show here that Rhizobium meliloti, the nitrogen-fixing endosymbiont of alfalfa (Medicago sativa), has a regulatory gene that is structurally homologous to previously characterized ntrC genes in enteric bacteria [2].
• Amino acid sequence comparisons of A. tumefaciens NTRC protein with NTRC sequences from Rhizobium meliloti, Bradyrhizobium sp. (Parasponia), Klebsiella pneumoniae, E. coli, and Salmonella typhimurium show strong sequence conservation supporting DNA hybridization data, demonstrating strong evolutionary homology among ntrC genes of Rhizobiaceae [3].

High impact information on ntrC

• In free-living conditions, P(II) is required for expression of the ntrC-dependent gene glnII and for adenylylation of glutamine synthetase I. P(II) is also required for efficient infection of alfalfa but not for expression of nitrogenase [4].
• We have determined the nucleotide sequences of two genes from Klebsiella pneumoniae, nifA, the nif-specific activator of transcription and ntrC, the bifunctional regulatory protein involved in 'nitrogen control'. These sequences differ significantly from those previously published [1].
• Promoters regulated by the glnG (ntrC) and nifA gene products share a heptameric consensus sequence in the -15 region [5].
• Identification and characterization of the Rhizobium meliloti ntrC gene: R. meliloti has separate regulatory pathways for activation of nitrogen fixation genes in free-living and symbiotic cells [2].
• In addition, R. meliloti ntrC is required for growth on media containing nitrate as the sole nitrogen source and for the ex planta transcription of several R. meliloti nif genes [2].

Biological context of ntrC

• Symbiotic nitrogen fixation by a nifA deletion mutant of Rhizobium meliloti: the role of an unusual ntrC allele [6].

Associations of ntrC with chemical compounds

• In addition to the nitrogen response, glutamate remodelled expression of carbon metabolism by inhibiting expression of the Entner-Doudoroff and pentose phosphate pathways, and by stimulating gluconeogenetic genes independently of ntrC [7].

Other interactions of ntrC

• These responses depended on both the ntrC and glnB nitrogen regulators [7].

Analytical, diagnostic and therapeutic context of ntrC

• Identification, cloning, and sequence analysis of the nitrogen regulation gene ntrC of Agrobacterium tumefaciens C58 [3].

References