Disease relevance of araC

• The start sites of the araC and araBAD gene messenger of E. coli were located by transcription in vitro from short DNA fragments, by high magnification electron microscopy and by genetic mapping [1].
• The araC gene of Citrobacter freundii [2].
• Overproducing araC protein with lambda-arabinose transducing phage [3].
• This DNA sequencing strategy was tested on a 1.4-kb DNA fragment containing the araC regulatory gene from Erwinia carotovora [4].
• The nucleotide sequence of the araC regulatory gene in Salmonella typhimurium LT2 [5].

High impact information on araC

• Transcription from the araBAD promoter requires araC protein plus arabinose and CAP protein plus cyclic AMP [1].
• The araC gene of Escherichia coli encodes a protein that binds the inducer L-arabinose to activate the transcription of three ara operons [6].
• We propose that the N-terminal half of AraC is essential for the formation of the DNA loops that are responsible for repression of araBAD and for autoregulation of araC [6].
• Negative regulation is accomplished by the repressing form of araC protein binding to a site in the regulatory region such that it stimultaneously blocks access of cyclic AMP receptor protein to two sites on the DNA, one site of which serves each of the two promoters [7].
• DNA sequence of the araC regulatory gene from Escherichia coli B/r [8].

Chemical compound and disease context of araC

• Previous studies have shown that heterologous protein expression can be tightly controlled using plasmids with the P(BAD) promoter of the arabinose operon of E. coli, and the araC gene, which is both a positive and negative regulator of the promoter [9].
• AraC protein from Escherichia coli has been further stabilized and characterized. pH is a critical variable in conferring stability. araC protein has a sedimentation coefficient of 4.0 +/- 0.2s on standardized 5%-20% glycerol gradients [10].
• Derivatives of the Escherichia coli drug resistance plasmid pMB-9 were constructed which contain the promoter from the lactose operon of E. coli fused to the araC gene of E. coli [11].

Biological context of araC

• In vitro protection studies with DNase I and dimethylsulfate showed that araC protein can specifically bind in this area to nucleotides lying at position -265 to -294 with respect to the araBAD operon promoter (PBAD) transcription start point [12].
• A deletion which does not recombine with any known point mutation in araC, delta(araCO)719, removes all but the last 22 codons of the gene [8].
• Equilibrium binding constraints and kinetics were determined for araC protein binding to the araI and the araO1 sites [13].
• The mechanisms of induction and repression were studied by observing the multiple interactions of RNA polymerase, cyclic AMP receptor protein and araC protein with short DNA fragments containing either the araC or araBAD promoter regions [13].
• These results suggest a complex mechanism for the inhibition of DNA replication by araC when it is misincorporated into DNA [14].

Anatomical context of araC

• Two versions of expression cassettes containing multiple cloning sites either with or without a ribosome binding site were placed under transcriptional control of the Escherichia coli BAD promoter and araC gene [15].

Associations of araC with chemical compounds

• In the presence of inducer, L-arabinose, araC protein binds with equal affinity to DNA fragments containing either of these sites [13].
• Regulation of the regulatory gene for the arabinose pathway, araC [16].
• Cytosine arabinoside (araC) is a potent antileukemic agent that is misincorporated into DNA in the course of its action [14].
• The aralc mutations allow low-level constitutive expression of ara-BAD in the absence of the positive regulatory protein coded for by the araC gene, whereas the araXc mutations allow expression of araBAD in the absence of the cyclic adenosine monophosphate receptor protein [17].
• The mutations were isolated on an araC-containing plasmid by hydroxylamine mutagenesis of plasmid DNA [18].

Other interactions of araC

• A 1.3-kb segment of Escherichia coli DNA containing the regulatory gene, araC, and the promoter of the araBAD operon was amplified by the polymerase chain reaction (PCR) and cloned into pUC18, resulting in plasmid pKB130 that produced the alpha fragment of beta-galactosidase upon addition of L-arabinose (L-ara) [19].

Analytical, diagnostic and therapeutic context of araC

• In vivo titration of araC protein [20].

References