1887

Abstract

The CobT enzyme of was shown to have NAD-dependent ADPribosyltransferase activity. The CobT enzyme transferred the ADPribosyl moiety of NAD onto 5,6-dimethylbenzimidazole (DMB) yielding a new dinucleotide, namely -5,6-dimethylbenzimidazole adenine dinucleotide (-DAD), whose identity was established by mass spectrometry. The -(--ribosyl)-5,6-dimethylbenzimidazoyl moiety (-ribazole) of -DAD was incorporated into adenosylcobalamin (AdoCbl) by cell-free extracts of , indicating that -DAD served as an intermediate of AdoCbl biosynthesis. The rate of transfer of the ADPribosyl moiety was slower than the rate of transfer of the phosphoribosyl moiety of nicotinate mononucleotide (NaMN) to DMB. The CobT enzyme displayed a low for NaMN (0·51 mM) relative to the one for NAD (9 mM); nicotinate adenine dinucleotide (NaAD) and nicotinamide mononucleotide (NMN) also served as substrates for CobT. In spite of the high of CobT for NAD, the latter is proposed to be a relevant physiological substrate of CobT, given that the intracellular concentrations of NaMN, NMN and NaAD in actively growing are undetectable. Evidence shows that extracts of contain an as-yet unidentified dinucleotide pyrophosphatase that can cleave -DAD into -ribazole-5′-P and AMP; -ribazole-5′-P can then enter the AdoCbl biosynthetic pathway.

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2003-04-01
2020-09-29
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References

  1. Blanche F., Thibaut D., Couder M., Muller J.-C.. 1990; Identification and quantitation of corrinoid precursors of cobalamin from Pseudomonas denitrificans by high-performance liquid chromatography. Anal Biochem189:24–29
    [Google Scholar]
  2. Bochner B. R., Ames B. N.. 1982; Complete analysis of cellular nucleotides by two-dimentional thin layer chromatography. J Biol Chem257:9759–9769
    [Google Scholar]
  3. Brachmann C. B., Sherman J. M., Devine S. E., Cameron E. E., Pillus L., Boeke J. D.. 1995; The SIR2 gene family, conserved from bacteria to humans, functions in silencing, cell cycle progression, and chromosomal stability. Genes Dev9:2888–2902
    [Google Scholar]
  4. Chan R. K., Botstein D., Watanabe T., Ogata Y.. 1972; Specialized transduction of tetracycline resistance by phage P22 in Salmonella typhimurium . II. Properties of a high transducing lysate. Virology50:883–898
    [Google Scholar]
  5. Cheong C. G., Escalante-Semerena J. C., Rayment I.. 1999; The three-dimensional structures of nicotinate mononucleotide : 5,6-dimethylbenzimidazole phosphoribosyltransferase (CobT) from Salmonella typhimurium complexed with 5,6-dimethybenzimidazole and its reaction products determined to 1·9 Å resolution. Biochemistry38:16125–16135
    [Google Scholar]
  6. Cheong C. G., Escalante-Semerena J. C., 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 Chem276:37612–37620
    [Google Scholar]
  7. Cheong C. G., Escalante-Semerena J. C., 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 Chem277:41120–41127
    [Google Scholar]
  8. Dalziel K., Dickinson F. M.. 1966; Purification of nicotinamide adenine dinucleotide. In Biochemical Preparations pp 84–88 Edited by Maehly A. C.. New York: Wiley;
    [Google Scholar]
  9. Davis R. W., Botstein D., Roth J. R.. 1980; A Manual for Genetic Engineering: Advanced Bacterial Genetics Cold Spring Harbor, NY: Cold Spring Harbor Laboratory Press;
    [Google Scholar]
  10. Dickinson F. M., Engel P. C.. 1977; The preparation of pure salt-free nicotinamide coenzymes. Anal Biochem82:523–531
    [Google Scholar]
  11. Friedmann H. C.. 1965; Partial purification and properties of a single displacement trans- N- glycosidase. J Biol Chem240:413–418
    [Google Scholar]
  12. Friedmann H. C., Harris D. L.. 1965; The formation of α -glycosidic 5′-nucleotides by a single displacement trans- N- glycosidase. J Biol Chem240:406–411
    [Google Scholar]
  13. Frye R. A.. 1999; Characterization of five human cDNAs with homology to the yeast SIR2 gene: Sir2-like proteins (sirtuins) metabolize NAD and may have protein ADP-ribosyltransferase activity. Biochem Biophys Res Commun260:273–279
    [Google Scholar]
  14. Fyfe J. A., Friedmann H. C.. 1969; Vitamin B12 biosynthesis: enzyme studies on the formation of the α -glycosidic nucleotide precursor. J Biol Chem244:1659–1666
    [Google Scholar]
  15. Imai S.-I., Armstrong C. M., Kaeberlein M., Guarente L.. 2000; Transcriptional silencing and longevity protein Sir2 is an NAD-dependent histone deacetylase. Nature403:795–800
    [Google Scholar]
  16. Lawrence J. G., Roth J. R.. 1996; Evolution of coenzyme B12 synthesis among enteric bacteria: evidence for loss and reacquisition of a multigene complex. Genetics142:11–24
    [Google Scholar]
  17. Lin S. J., Defossez P. A., Guarente L.. 2000; Requirement of NAD and SIR2 for life-span extension by calorie restriction in Saccharomyces cerevisiae . Science289:2126–2128
    [Google Scholar]
  18. Maggio-Hall L. A., Escalante-Semerena J. C.. 1999; In vitro synthesis of the nucleotide loop of adenosylcobalamin by Salmonella typhimurium enzymes. Proc Natl Acad Sci U S A96:11798–11803
    [Google Scholar]
  19. O'Toole G. A., Rondon M. R., Escalante-Semerena J. C.. 1993; Analysis of mutants of Salmonella typhimurium defective in the synthesis of the nucleotide loop of cobalamin. J Bacteriol175:3317–3326
    [Google Scholar]
  20. O'Toole G. A., Trzebiatowski J. R., Escalante-Semerena J. C.. 1994; The cobC gene of Salmonella typhimurium codes for a novel phosphatase involved in the assembly of the nucleotide loop of cobalamin. J Biol Chem269:26503–26511
    [Google Scholar]
  21. Rine J., Herskowitz I.. 1987; Four genes responsible for a position effect on expression from HML and HMR in Saccharomyces cerevisiae . Genetics116:9–22
    [Google Scholar]
  22. Smith J. S., Brachmann C. B., Celic I.. 8 other authors 2000; A phylogenetically conserved NAD+-dependent protein deacetylase activity in the Sir2 protein family. Proc Natl Acad Sci U S A97:6658–6663
    [Google Scholar]
  23. Starai V. J., Celic I., Cole R. N., Boeke J. D., Escalante-Semerena J. C.. 2002; Sir2-dependent activation of acetyl-coenzyme A synthetase by deacetylation of an active lysine. Science298:2390–2392
    [Google Scholar]
  24. Starai V. J., Takahashi H., Boeke J. D., Escalante-Semerena J. C.. 2003; Short-chain fatty acid activation by acyl-coenzyme A synthetases requires SIR2 protein function. Genetics163:545–555
    [Google Scholar]
  25. Tabor S.. others 1990; Expression using the T7 RNA polymerase/promoter system. In Current Protocols in Molecular Biology p16.12.11 Edited by Ausubel F. M. New York: Wiley;
    [Google Scholar]
  26. Tanner K. G., Landry J., Sternglanz R., Denu J. M.. 2000; Silent information regulator family of NAD-dependent histone/protein deacetylases generates a unique product, 1- O -acetyl-ADP-ribose. Proc Natl Acad Sci U S A97:14178–14182
    [Google Scholar]
  27. Tanny J. C., Dowd G. J., Huang J., Hilz H., Moazed D.. 1999; An enzymatic activity in the yeast Sir2 protein that is essential for gene silencing. Cell99:735–745
    [Google Scholar]
  28. Trzebiatowski J. R., Escalante-Semerena J. C.. 1997; Purification and characterization of CobT, the nicotinate mononucleotide : 5,6-dimethylbenzimidazole phosphoribosyltransferase enzyme from Salmonella typhimurium LT2. J Biol Chem272:17662–17667
    [Google Scholar]
  29. Trzebiatowski J. R., O'Toole G. A., Escalante-Semerena J. C.. 1994; The cobT gene of Salmonella typhimurium encodes the NaMN : 5,6-dimethylbenzimidazole phosphoribosyl transferase responsible for the synthesis of N 1-(5-phospho- α -d-ribosyl)-5,6-dimethylbenzimidazole, an intermediate in the synthesis of the nucleotide loop of cobalamin. J Bacteriol176:3568–3575
    [Google Scholar]
  30. Tsang A. W., Escalante-Semerena J. C.. 1998; CobB, a new member of the SIR2 family of eucaryotic regulatory proteins, is required to compensate for the lack of nicotinate mononucleotide : 5,6-dimethylbenzimidazole phosphoribosyltransferase activity in cobT mutants during cobalamin biosynthesis in Salmonella typhimurium LT2. J Biol Chem273:31788–31794
    [Google Scholar]
  31. Warren M. J., Raux E., Schubert H. L., Escalante-Semerena J. C.. 2002; The biosynthesis of AdoCbl (vitamin B12). Nat Prod Rep19:390–412
    [Google Scholar]
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