Phosphoribosyl-N-formylglycineamide (or FormylGlycinAmideRibotide, FGAR) is a biochemical intermediate in the formation of purine nucleotides via inosine-5-monophosphate, and hence is a building block for DNA and RNA.[1][2] The vitamins thiamine[3] and cobalamin[4] also contain fragments derived from FGAR.[5]

FGAR is formed when the enzyme phosphoribosylglycinamide formyltransferase adds a formyl group from 10-formyltetrahydrofolate to glycineamide ribonucleotide (GAR) in reaction EC 2.1.2.2:[6]

GAR + 10-formyltetrahydrofolate → FGAR + tetrahydrofolate

The biosynthesis pathway next converts FGAR to an amidine by the action of phosphoribosylformylglycinamidine synthase (EC 6.3.5.3), transferring an amino group from glutamine and giving 5'-phosphoribosylformylglycinamidine (FGAM) in a reaction that also requires ATP:[6]

FGAR + ATP + glutamine + H2O → FGAM + ADP + glutamate + Pi

See also

References

  1. ^ R. Caspi (2009-01-13). "Pathway: 5-aminoimidazole ribonucleotide biosynthesis I". MetaCyc Metabolic Pathway Database. Retrieved 2022-02-02.
  2. ^ Gupta, Rani; Gupta, Namita (2021). "Nucleotide Biosynthesis and Regulation". Fundamentals of Bacterial Physiology and Metabolism. pp. 525–554. doi:10.1007/978-981-16-0723-3_19. ISBN 978-981-16-0722-6. S2CID 234897784.
  3. ^ Chatterjee, Abhishek; Hazra, Amrita B.; Abdelwahed, Sameh; Hilmey, David G.; Begley, Tadhg P. (2010). "A "Radical Dance" in Thiamin Biosynthesis: Mechanistic Analysis of the Bacterial Hydroxymethylpyrimidine Phosphate Synthase". Angewandte Chemie International Edition. 49 (46): 8653–8656. doi:10.1002/anie.201003419. PMC 3147014. PMID 20886485.
  4. ^ R. Caspi (2019-09-23). "Pathway: 5-hydroxybenzimidazole biosynthesis (anaerobic)". MetaCyc Metabolic Pathway Database. Retrieved 2022-02-10.
  5. ^ Mehta, Angad P.; Abdelwahed, Sameh H.; Fenwick, Michael K.; Hazra, Amrita B.; Taga, Michiko E.; Zhang, Yang; Ealick, Steven E.; Begley, Tadhg P. (2015). "Anaerobic 5-Hydroxybenzimidazole Formation from Aminoimidazole Ribotide: An Unanticipated Intersection of Thiamin and Vitamin B12 Biosynthesis". Journal of the American Chemical Society. 137 (33): 10444–10447. doi:10.1021/jacs.5b03576. PMC 4753784. PMID 26237670.
  6. ^ a b Welin, Martin; Grossmann, Jörg Günter; Flodin, Susanne; Nyman, Tomas; Stenmark, Pål; Trésaugues, Lionel; Kotenyova, Tetyana; Johansson, Ida; Nordlund, Pär; Lehtiö, Lari (2010). "Structural studies of tri-functional human GART". Nucleic Acids Research. 38 (20): 7308–7319. doi:10.1093/nar/gkq595. PMC 2978367. PMID 20631005.