Disease relevance of pyrE

• Attenuation in the rph-pyrE operon of Escherichia coli and processing of the dicistronic mRNA [1].

High impact information on pyrE

• Deletion of the start of this 238 codons long ORF gene resulted in a dramatic fall in the level of pyrE expression, indicating that the two genes (ORF and pyrE) constitute an operon [2].
• The nucleotide sequence of this DNA revealed the existence of an open reading frame (ORF) of 238 codons that ends 68 nucleotide residues upstream to the structure start of pyrE, just prior to the GC-rich symmetry region of a sequence with features characteristic of a rho-independent transcription terminator [2].
• Most significantly, retron-Ec107 was inserted into the E. coli genome by replacing a 34bp intergenic sequence between the pyrE and ttk genes located at 82 min on the E. coli chromosome [3].
• Expression of the Escherichia coli pyrE gene is regulated by transcription attenuation in the intercistronic orfE-pyrE region and modulated by the distance between the transcribing RNA polymerase and the leading ribosome as a function of the supply of UTP and GTP [4].
• This phenotype, previously seen in rpsL1204 strains whose ribosomes are pseudodependent on streptomycin and work at suboptimal elongation rate, indicates that RNA polymerase escapes from the ribosomes in the pyrE attenuator region in the nusA mutant [4].

Chemical compound and disease context of pyrE

• We have determined the 2.4 angstrom structure of Escherichia coli OPRTase, ligated with sulfate, by molecular replacement and refined the structure to an R-factor of 18.3% for all data [5].

Biological context of pyrE

• We have substituted on a plasmid the native promoter of the Escherichia coli rph-pyrE operon with an inducible transcription-initiation signal [1].
• The results indicate that the NusA protein is required for proper regulation of pyrE gene expression and is involved, together with the NTP pools, in maintaining the coupling between transcription and translation in the pyrE attenuator region by inhibiting RNA chain elongation [4].
• Nucleotide sequence of the Escherichia coli pyrE gene and of the DNA in front of the protein-coding region [6].
• The pyrE gene is transcribed in a counter-clock wise direction from the E. coli chromosome as an mRNA with a considerable leader segment in front of the protein-coding region [6].
• A flexible loop at the dimer interface is a part of the active site of the adjacent monomer of Escherichia coli orotate phosphoribosyltransferase [5].

Associations of pyrE with chemical compounds

• In this communication we show that pyrE expression is hyper-repressed in vivo following addition of uracil in strains carrying the nusAcs10 mutation [4].
• Orotate phosphoribosyltransferase (OPRTase) is involved in the biosynthesis of pyrimidine nucleotides [5].

Other interactions of pyrE

• However, the dicistronic rph-pyrE transcript was rapidly processed into two monocistronic mRNA units, and a cleavage site was mapped near the attenuator in the intercistronic region, close to the site where transcription was terminated in high-UTP pools [1].
• Two mutants with the InsTet(G-)1 insertion in the gene pyrE or argA survived this procedure, indicating a reduced intracellular growth rate in J774-A.1 cells [7].
• This paper described a study of pyrBI and pyrE gene regulation in cells where the ribosomes move slowly as a result of mutation in rpsL [8].

References