xpt [2017-05-26 16:20:52]

xanthine phosphoribosyltransferase

locus: BSU22070

pI: 5.84

mw: 20.89 kDa

protein length: 194 aa

gene length: 582 bp

function: purine salvage and interconversion

product: xanthine phosphoribosyltransferase

essential: no

ec: 2.4.2.22

synonyms

Genomic Context

categories

• [category|SW 2|Metabolism] → [category|SW 2.5|Nucleotide metabolism] → [category|SW 2.5.2|Biosynthesis/ acquisition of nucleotides] → [category|SW 2.5.2.3|Purine salvage and interconversion]
• [category|SW 3|Information processing] → [category|SW 3.5|Targets of second messengers] → [category|SW 3.5.3|Targets of (p)ppGpp]

Gene

Coordinates: 2,319,440 → 2,320,024

The protein

Catalyzed reaction/ biological activity

• XMP diphosphate = 5-phospho-alpha-D-ribose 1-diphosphate xanthine (according to Swiss-Prot)

Structure

• [PDB|1Y0B], [PDB|2FXV] (complex with GMP), [PDB|1Y27] (the riboswitch in complex with guanine)

[SW|Localization]

• cell membrane (according to Swiss-Prot)

Additional information

• subject to Clp-dependent proteolysis upon glucose starvation [PubMed|17981983]

Expression and Regulation

Operons

• genes: [gene|02C84C9A8C0008CC253CBF13584A4B5B2D2B510C|xpt]-[gene|7D56F85FBD3AAC66607DD7465592EEAE09D61C98|pbuX]
  description: [Pubmed|9098051]

  sigma factors

  • [protein|360F48D576DE950DF79C1A2677B7A35A8D8CC30C|SigA]: sigma factor, [Pubmed|9098051], in [regulon|360F48D576DE950DF79C1A2677B7A35A8D8CC30C|SigA regulon]

  regulatory mechanism

  • [regulon|G-box|G-box]: termination, [SW|riboswitch] [Pubmed|9098051,12787499], in [regulon|G-box|G-box]
  • [protein|A8C82F5825DE0921DA6B4ACDE0CC31EC7749273C|PurR]: repression, (molecular inducer: PRPP) [Pubmed|11591660], in [regulon|A8C82F5825DE0921DA6B4ACDE0CC31EC7749273C|PurR regulon]

  regulation

  • induced in the absence of guanine ([SW|G-box]) [Pubmed|12787499]

Biological materials

Mutant

• MGNA-A870 (xpt::erm), available at the [https://shigen.nig.ac.jp/bsub/resource/strainGeneDisrupted/detail/870 NBRP B. subtilis, Japan]

lacZ fusion

• pGP430 (in [SW|pAC7]), available in [SW|Jörg Stülke]'s lab

References

• 16716072,9098051,12923093,15629952,11591660,15610857,20200045,11591660,20204714,26704707,27941758