Nucleotide sequence of the argR gene of Escherichia coli K-12 and isolation of its product, the arginine repressor (original) (raw)
Related papers
Nucleic Acids Research, 1983
We compare the nucleotide sequences of the regulatory regions of five genes or groups of genes of the arginine regulon of Escherichia coli K-12 : argF, argl, argR, the bipolar argECBH operon and the carAB operon. All these regions harbour one or two copies of a conserved 18 bp sequence which appears to constitute the basic arginine operator sequence (ARG box) . We discuss the influence of ARG box copy number, degree of dyad symmetry, base composition, and position relative to the cognate promoter site on the derepression-repression ratios of the genes of the regulon. A novel hypothesis, based on structural considerations, is also put forward to account for the absence ot attenuation control.
Microbiology (Reading, England), 2006
Analysis of the response to arginine of the Escherichia coli K-12 transcriptome by microarray hybridization and real-time quantitative PCR provides the first coherent quantitative picture of the ArgR-mediated repression of arginine biosynthesis and uptake genes. Transcriptional repression was shown to be the major control mechanism of the biosynthetic genes, leaving only limited room for additional transcriptional or post-transcriptional regulation. The art genes, encoding the specific arginine uptake system, are subject to ArgR-mediated repression, with strong repression of artJ, encoding the periplasmic binding protein of the system. The hisJQMP genes of the histidine transporter (part of the lysine-arginine-ornithine uptake system) were discovered to be a part of the arginine regulon. Analysis of their control region with reporter gene fusions and electrophoretic mobility shift in the presence of pure ArgR repressor showed the involvement in repression of the ArgR protein and an ...
Molecular Microbiology, 1989
The region required for regulation of a previously characterized arginine-regulatable promoter upstream from the argC gene in the argCAEBD-cpa-argFc\uster of Bacillus subtilis was defined by integration of argC-lacZ translational fusions into the chromosome at a site distant from the arginine loci. Some sequence similarity was detected between the argC regulatory region and the well-characterized Escherichia coli arginine operators (ARG boxes). This similarity was shown to be functional /n vivo in that the B. subtilis repressor regulated the E. co//arginine genes, but the £. coli repressor, even when encoded by a multicopy plasmid, could not repress the B. subtilis argC promoter. In vitro binding studies using purified repressors on DNA fragments encoding operators from both £. coli and B. subtilis demonstrated interactions by both proteins.
1997
The goal of this work was to construct Escherichia coli strains capable of enhanced arginine production. The arginine biosynthetic capacity of previously engineered E. coli strains with a derepressed arginine regulon was limited by the availability of endogenous ornithine (M. Tuchman, B. S. Rajagopal, M. T. McCann, and M. H. Malamy, Appl. Environ. Microbiol. 63:33-38, 1997). Ornithine biosynthesis is limited due to feedback inhibition by arginine of N-acetylglutamate synthetase (NAGS), the product of the argA gene and the first enzyme in the pathway of arginine biosynthesis in E. coli. To circumvent this inhibition, the argA genes from E. coli mutants with feedback-resistant (fbr) NAGS were cloned into plasmids that contain "arg boxes," which titrate the ArgR repressor protein, with or without the E. coli carAB genes encoding carbamyl phosphate synthetase and the argI gene for ornithine transcarbamylase. The free arginine production rates of "arg-derepressed" E. coli cells overexpressing plasmid-encoded carAB, argI, and fbr argA genes were 3-to 15-fold higher than that of an equivalent system overexpressing feedback-sensitive wild-type (wt) argA. The expression system with fbr argA produced 7-to 35-fold more arginine than a system overexpressing carAB and argI genes on a plasmid in a strain with a wt argA gene on the chromosome. The arginine biosynthetic capacity of arg-derepressed DH5␣ strains with plasmids containing only the fbr argA gene was similar to that of cells with plasmids also containing the carAB and argI genes. Plasmids containing wt or fbr argA were stably maintained under normal growth conditions for at least 18 generations. DNA sequencing identified different point mutations in each of the fbr argA mutants, specifically H15Y, Y19C, S54N, R58H, G287S, and Q432R.
Journal of Bacteriology, 2002
Bacillus stearothermophilus ArgR binds efficiently to the Escherichia coli carAB operator, whereas the E. coli repressor binds very poorly to the argCo operator of B. stearothermophilus. In order to elucidate this contradictory behavior between ArgRs, we constructed chimeric proteins by swapping N-terminal DNA-binding and C-terminal oligomerization domains or by exchanging the linker peptide. Chimeras carrying the E. coli DNA-binding domain and the B. stearothermophilus oligomerization domain showed sequence-nonspecific rather than sequence-specific interactions with arg operators. Chimeras carrying the B. stearothermophilus DNA-binding domain and E. coli oligomerization domain exhibited a high DNA-binding affinity for the B. stearothermophilus argCo and E. coli carAB operators and repressed the reporter-gene transcription from the B. stearothermophilus PargCo control region in vitro; arginine had no effect on, and indeed even decreased, their DNA-binding affinity. With the protein array method, we showed that the wild-type B. stearothermophilus ArgR and derivatives of it containing only the exchanged linker from E. coli ArgR or carrying the B. stearothermophilus DNA-binding domain along with the linker and the alpha4 regions were able to bind argCo containing the single Arg box. This binding was weaker than binding to the two-box operator but was no longer arginine dependent. Several lines of observations indicate that the alpha4 helix in the oligomerization domain and the linker peptide can contribute to the recognition of single or double Arg boxes and therefore to the operator DNA-binding specificity in similar but not identical ArgR repressors from two distant bacteria.
Gene, 1989
In ~ucjl~us s~~~Z~, arginine represses its biosynthetic enzymes and activates its catabolic ones via a regulator gene ahrC. A 6.2-kb EcoRI fragment of B. subtilis chromosomal DNA that includes the ah& gene has previously been cloned. Gene ah& was localised in a 0.8-kb EiindIII sub-fragment whose nucleotide sequence was determined. An open reading frame (ORF) was present whose translated amino acid sequence showed homology to that of the Esche~chiu coli arginine repressor encoded by that organism's argR gene. That this ORF corresponded to ah& was confu?ned by (i) the location of the transposon in an uhrC: : Tn92 7 insertion mutant within the ORF; and (ii) by the appearance of an AhrC-phenotype when plasmids carrying restriction fragments lying wholly within this ORF were permitted to integrate by Campbell-type recombination into the B. ~btil~s c~omosome. This represents the fast desc~ption of a repressor in a 'housekeeping' biosynthetic system in a Bacilfus, and indeed of homology between regulatory proteins for any 'housekeeping' system across such a wide taxonomic barrier among prokaryotes.
Two Arginine Repressors Regulate Arginine Biosynthesis in Lactobacillus plantarum
Journal of Bacteriology, 2004
The repression of the carAB operon encoding carbamoyl phosphate synthase leads to Lactobacillus plantarum FB331 growth inhibition in the presence of arginine. This phenotype was used in a positive screening to select spontaneous mutants deregulated in the arginine biosynthesis pathway. Fourteen mutants were genetically characterized for constitutive arginine production. Mutations were located either in one of the arginine repressor genes (argR1 or argR2) present in L. plantarum or in a putative ARG operator in the intergenic region of the bipolar carAB-argCJBDF operons involved in arginine biosynthesis. Although the presence of two ArgR regulators is commonly found in gram-positive bacteria, only single arginine repressors have so far been well studied in Escherichia coli or Bacillus subtilis. In L. plantarum, arginine repression was abolished when ArgR1 or ArgR2 was mutated in the DNA binding domain, or in the oligomerization domain or when an A123D mutation occurred in ArgR1. A123, equivalent to the conserved residue A124 in E. coli ArgR involved in arginine binding, was different in the wild-type ArgR2. Thus, corepressor binding sites may be different in ArgR1 and ArgR2, which have only 35% identical residues. Other mutants harbored wild-type argR genes, and 20 mutants have lost their ability to grow in normal air without carbon dioxide enrichment; this revealed a link between arginine biosynthesis and a still-unknown CO 2 -dependent metabolic pathway. In many gram-positive bacteria, the expression and interaction of different ArgR-like proteins may imply a complex regulatory network in response to environmental stimuli.
Arginine control of transcription of argECBH messenger ribonucleic acid in Escherichia coli
Journal of bacteriology, 1972
The level of messenger ribonucleic acid specific for the argECBH gene cluster (arg-mRNA) of Escherichia coli was measured by deoxyribonucleic acid-ribonucleic acid hybridization in a number of strains. During the first 10 min after removal of arginine (derepression), the rate of arg-mRNA accumulation was six to ten times greater than that found in arginine-repressed argR(+) cells. In the absence of arginine, l-canavanine (200 mug/ml) repressed arg-mRNA synthesis to a level only 20 to 30% lower than that found after arginine deprivation. High levels of arg-mRNA were produced by argR(-) strains with or without added arginine. Within about 2 min after arginine addition to argR(+) cells, the rate of synthesis of arg-mRNA reached the repressed level. Likewise, 2.5 min after rifampin addition, all transcription of arg-mRNA was completed. These data are consistent with the view that arginine signals repression by inhibiting the initiation of transcription of arg-mRNA mediated in some way b...
Journal of Bacteriology, 1975
The accumulation or ornithine, citrulline, and possibly acetylornithine by Escherichia coli K-12 arginineless mutants provided with acetylarginine as source of arginine causes severe growth inhibition. This occurs under conditions where comparable derivatives of E. coli W (Bollon and Vogel, 1973) show little or no growth inhibition. The same conditions, which have been reported to cause noncorrelative synthesis of acetylornithinase and argininosuccinase in E. coli W (Bollon and Vogel, 1973), do not alter the correlative pattern of enzyme synthesis observed in E. coli K-12. Moreover, previously reported effects of ornithine and citrulline on repression of the arginine regulon in E. coli W are not observed in the K-12 strains examined. The bearing of these observations on possible differences between the mechanism of enzyme repression operating in the two types of strains cannot yet be fully evaluated; it is, however, clear that considerable care should be exercised before extrapolati...