Disease relevance of pobR

• Identification of the transcriptional activator pobR and characterization of its role in the expression of pobA, the structural gene for p-hydroxybenzoate hydroxylase in Acinetobacter calcoaceticus [1].
• The pobR gene was placed under control of a lac promoter in an expression vector, and the recombinant plasmid inducibly expressed high levels of PobR in Escherichia coli [2].
• Analysis of the pobA and pobR genes controlling expression of p-hydroxybenzoate hydroxylase in Azotobacter chroococcum [3].

High impact information on pobR

• The genes from Azotobacter chroococcum encoding p-hydroxybenzoate hydroxylase (pobA) and its regulatory protein (pobR) were cloned from a genomic library and sequenced [3].
• Combining localized PCR mutagenesis and natural transformation in direct genetic analysis of a transcriptional regulator gene, pobR [4].
• PobR binds specifically to DNA in the pobA-pobR intergenic region, and this binding does not appear to be influenced by p-hydroxybenzoate, the inducer of pobA expression [2].
• The chromosome of A. calcoaceticus strain ADP1 contains seven copies of IS1236 which appears to insert preferentially into pobR, the transcriptional activator of the structural gene for p-hydroxybenzoate hydroxylase [5].

Biological context of pobR

• The nucleotide sequence of pobR was determined, and the activator gene was shown to be transcribed divergently from pobA; the genes are separated by 134 DNA base pairs [1].
• The pobA and pobR genes are divergently transcribed and separated by 134 bp in the Acinetobacter calcoaceticus chromosome [2].
• A frame-shift mutation introduced into the pobR gene prevented expression of p-hydroxybenzoate hydroxylase, indicating that PobR is the protein required for transcription of pobA [3].

Associations of pobR with chemical compounds

• Prior to this investigation, the only known regulatory gene in the pca-qui-pob cluster was pobR, which encodes a transcriptional activator that responds to p-hydroxybenzoate and activates transcription of pobA [6].

Analytical, diagnostic and therapeutic context of pobR

• This trait allowed selection of mutant strains in which pobR function had been impaired by nucleotide substitutions introduced by PCR replication errors [7].
• Sequence analysis of 89 of the mutant pobR alleles showed that the mutations were predominantly single-nucleotide substitutions broadly distributed within pobR [4].
• Surface plasmon resonance was used to determine the ability of mutant PobR proteins to bind to DNA in the pobA-pobR intergenic region [7].

References