Nicotinate-nucleotide-dimethylbenzimidazole phosphoribosyltransferase

From Wikipedia, the free encyclopedia

In enzymology, a nicotinate-nucleotide-dimethylbenzimidazole phosphoribosyltransferase (EC 2.4.2.21) is an enzyme that catalyzes the chemical reaction

beta-nicotinate D-ribonucleotide + 5,6-dimethylbenzimidazole $\rightleftharpoons$ nicotinate + alpha-ribazole 5'-phosphate

Thus, the two substrates of this enzyme are beta-nicotinate D-ribonucleotide and 5,6-dimethylbenzimidazole, whereas its two products are nicotinate and alpha-ribazole 5'-phosphate.

This enzyme belongs to the family of glycosyltransferases, specifically the pentosyltransferases. The systematic name of this enzyme class is nicotinate-nucleotide:5,6-dimethylbenzimidazole phospho-D-ribosyltransferase. Other names in common use include CobT, nicotinate mononucleotide-dimethylbenzimidazole phosphoribosyltransferase, nicotinate ribonucleotide:benzimidazole (adenine) phosphoribosyltransferase, nicotinate-nucleotide:dimethylbenzimidazole phospho-D-ribosyltransferase, and nicotinate mononucleotide (NaMN):5,6-dimethylbenzimidazole phosphoribosyltransferase. This enzyme participates in the metabolism of riboflavin, porphyrin and chlorophyll.

1 Structural studies
2 References
3 External links
- 3.1 Gene Ontology (GO) codes

[edit] Structural studies

As of late 2007, 28 structures have been solved for this class of enzymes, with PDB accession codes 1D0S, 1D0V, 1JH8, 1JHA, 1JHM, 1JHP, 1JHQ, 1JHR, 1JHU, 1JHV, 1JHX, 1JHY, 1L4B, 1L4E, 1L4F, 1L4G, 1L4H, 1L4K, 1L4L, 1L4M, 1L4N, 1L5F, 1L5K, 1L5L, 1L5M, 1L5N, 1L5O, and 1WX1.

[edit] References

IUBMB entry for 2.4.2.21
BRENDA references for 2.4.2.21 (Recommended.)
PubMed references for 2.4.2.21
PubMed Central references for 2.4.2.21
Google Scholar references for 2.4.2.21
Friedmann HC (1965). "Partial Purification and Properties of a Single Displacement Trans-N-Glycosidase". J. Biol. Chem. 240: 413–8. PMID 14253445.
Friedmann HC, Fyfe JA (1969). "Pseudovitamin B 12 biosynthesis. Enzymatic formation of a new adenylic acid, 7-alpha-D-ribofuranosyladenine 5'-phosphate". J. Biol. Chem. 244: 1667–71. PMID 5780835.
Fyfe JA, Friedmann HC (1969). "Vitamin B 12 biosynthesis. Enzyme studies on the formation of the alpha-glycosidic nucleotide precursor". J. Biol. Chem. 244: 1659–66. PMID 4238408.
Cauchois L, Thibaut D, Debussche L, Crouzet J (1991). "Genetic analysis, nucleotide sequence, and products of two Pseudomonas denitrificans cob genes encoding nicotinate-nucleotide: dimethylbenzimidazole phosphoribosyltransferase and cobalamin (5'-phosphate) synthase". J. Bacteriol. 173: 6066–73. PMID 1917841.
Cheong CG, Escalante-Semerena JC, Rayment I (2001). "Structural investigation of the biosynthesis of alternative lower ligands for cobamides by nicotinate mononucleotide: 5,6-dimethylbenzimidazole phosphoribosyltransferase from Salmonella enterica". J. Biol. Chem. 276: 37612–20. doi:10.1074/jbc.M105390200. PMID 11441022.
Cheong CG, Escalante-Semerena JC, Rayment I (2002). "Capture of a labile substrate by expulsion of water molecules from the active site of nicotinate mononucleotide:5,6-dimethylbenzimidazole phosphoribosyltransferase (CobT) from Salmonella enterica". J. Biol. Chem. 277: 41120–7. doi:10.1074/jbc.M203535200. PMID 12101181.