Disease relevance of rph

• The Escherichia coli K-12 "wild types" W3110 and MG1655 have an rph frameshift mutation that leads to pyrimidine starvation due to low pyrE expression levels [1].
• The Bacillus subtilis homolog of the Escherichia coli morphogene orfE (of the mre operon) has been identified [2].
• A gene function carried by a plasmid, causing arrest of cell division in Escherichia coli, has been identified as the product of a short open reading frame of the prophage Rac, previously designated orfE, expressed only under conditions of prophage induction [3].
• PNPase structure analysis has been performed in Streptomyces antibioticus; this revealed the presence of five domains: two ribonuclease PH (RPH)-like (pnp1 and pnp2), one alpha helical, one KH, and one S1 domains [4].

High impact information on rph

• Washed membranes from cells overexpressing orfE display approximately 2000-fold higher specific activity of 4'-kinase than membranes from cells with vector alone [5].
• In this paper we report the construction of a plasmid, which overexpresses the orfE and pyrE gene products substantially, as well as the purification of the OrfE protein by ammonium sulfate precipitation and chromatography on phosphocellulose [6].
• Mutational analysis of msbA indicates that it may form an operon with a downstream gene, orfE, and that both of these genes are essential for bacterial viability under all growth conditions tested [7].
• The orfE, orfX, and orfY genes were inactivated on the bacterial chromosome by deletion-insertion mutagenesis using a kanamycin resistance cassette [8].
• The nucleotide sequence of two kilobase pairs (kb) 5' to the orfE-pyrE operon has been determined [8].

Chemical compound and disease context of rph

• After introduction of a plasmid carrying the rph-pyrE operon from strain HfrH, the growth rates were no longer stimulated by uracil and the levels of aspartate transcarbamylase were low and similar to the levels observed for other strains of E. coli K-12, E. coli B, and Salmonella typhimurium [1].

Biological context of rph

• DNA sequencing revealed that a GC base pair was missing near the end of the rph gene of W3110 [1].
• The cloned B. subtilis rph gene also suppresses the cold-sensitive phenotype of other unrelated cold-sensitive mutants of E. coli, but not the temperature-sensitive phenotype of three temperature-sensitive mutants, including the nusA11(Ts) mutant, that were tested [9].
• Attenuation in the rph-pyrE operon of Escherichia coli and processing of the dicistronic mRNA [10].
• The responsible gene encodes an open reading frame that is greater than 50% identical at the amino acid level to the E. coli rph gene, which was formerly called orfE [9].
• Inactivation of these genes (designated orfE, orfX and orfY) by crossing the KmR-cassette-disrupted orf into the chromosome indicated that they were not required during exponential growth (Poulsen et al., Mol., Microbiol., 1989 b) [11].

Anatomical context of rph

• 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 [12].

References