UniProt functional annotation for P39765



	UniProt functional annotation for P39765

UniProt code: P39765.

Organism: Bacillus subtilis (strain 168).

Taxonomy: Bacteria; Firmicutes; Bacilli; Bacillales; Bacillaceae; Bacillus.

Function: Regulates transcriptional attenuation of the pyrimidine nucleotide (pyr) operon by binding in a uridine-dependent manner to specific sites on pyr mRNA. This disrupts an antiterminator hairpin in the RNA and favors formation of a downstream transcription terminator, leading to a reduced expression of downstream genes.

Function: Also displays a weak uracil phosphoribosyltransferase activity which is not physiologically significant.

Catalytic activity: Reaction=diphosphate + UMP = 5-phospho-alpha-D-ribose 1-diphosphate + uracil; Xref=Rhea:RHEA:13017, ChEBI:CHEBI:17568, ChEBI:CHEBI:33019, ChEBI:CHEBI:57865, ChEBI:CHEBI:58017; EC=2.4.2.9; Evidence={ECO:0000269|PubMed:7798145};

Biophysicochemical properties: pH dependence: Optimum pH is 8.2 for UPRTase activity.;

Subunit: Homodimer and homohexamer; in equilibrium.

Mass spectrometry: Mass=20263; Mass_error=2; Method=Electrospray; Evidence={ECO:0000269|PubMed:9488732};

Miscellaneous: Mutagenesis studies identified four amino acid residues that seem to be involved directly in binding of the protein to pyr mRNA: Thr-18, His-22, Arg-141 and Arg-146. Arg-27 and Lys-152 were also likely to be involved in RNA-binding, but mutations may have altered their subunit-subunit interactions. Arg-19 was implicated in pyr regulation, but a specific role in RNA-binding could not be demonstrated.

Miscellaneous: UMP and UTP increase the affinity of PyrR for RNA.

Similarity: Belongs to the purine/pyrimidine phosphoribosyltransferase family. PyrR subfamily. {ECO:0000305}.

Annotations taken from UniProtKB at the EBI.


Organism:		Bacillus subtilis (strain 168).
Taxonomy:		Bacteria; Firmicutes; Bacilli; Bacillales; Bacillaceae; Bacillus.



Function:		Regulates transcriptional attenuation of the pyrimidine nucleotide (pyr) operon by binding in a uridine-dependent manner to specific sites on pyr mRNA. This disrupts an antiterminator hairpin in the RNA and favors formation of a downstream transcription terminator, leading to a reduced expression of downstream genes.



Function:		Also displays a weak uracil phosphoribosyltransferase activity which is not physiologically significant.


Catalytic activity:		Reaction=diphosphate + UMP = 5-phospho-alpha-D-ribose 1-diphosphate + uracil; Xref=Rhea:RHEA:13017, ChEBI:CHEBI:17568, ChEBI:CHEBI:33019, ChEBI:CHEBI:57865, ChEBI:CHEBI:58017; EC=2.4.2.9; Evidence={ECO:0000269\|PubMed:7798145};
Biophysicochemical properties:		pH dependence: Optimum pH is 8.2 for UPRTase activity.;
Subunit:		Homodimer and homohexamer; in equilibrium.
Mass spectrometry:		Mass=20263; Mass_error=2; Method=Electrospray; Evidence={ECO:0000269\|PubMed:9488732};
Miscellaneous:		Mutagenesis studies identified four amino acid residues that seem to be involved directly in binding of the protein to pyr mRNA: Thr-18, His-22, Arg-141 and Arg-146. Arg-27 and Lys-152 were also likely to be involved in RNA-binding, but mutations may have altered their subunit-subunit interactions. Arg-19 was implicated in pyr regulation, but a specific role in RNA-binding could not be demonstrated.
Miscellaneous:		UMP and UTP increase the affinity of PyrR for RNA.
Similarity:		Belongs to the purine/pyrimidine phosphoribosyltransferase family. PyrR subfamily. {ECO:0000305}.