2.0 2012-05-31 14:06:32 -0600 2015-10-02 02:25:46 -0600 ECMDB04147 M2MDB000637 Ribose-1-phosphate Ribose 1-phosphate is an intermediate in the metabolism of Pyrimidine and the metabolism of Nicotinate and nicotinamide. It is a substrate for Uridine phosphorylase 2, Phosphoglucomutase, Purine nucleoside phosphorylase and Uridine phosphorylase 1. Ribose 1-phosphate can be formed from guanosine through the action of purine nucleoside phosphorylase. Ribose 1-phosphate can also act as a ribose donor in the synthesis of xanthosine as catalyzed by the same enzyme (purine nucleoside phosphorylase). The presence of guanase, which irreversibly converts guanine to xanthine, affects the overall process of guanosine transformation. The activated ribose moiety in Ribose 1-phosphate which stems from the catabolism of purine nucleosides can be transferred to uracil and, in the presence of ATP, used for the synthesis of pyrimidine nucleotides; therefore, purine nucleosides can act as ribose donors for the salvage of pyrimidine bases. (PMID: 9133638) &alpha;-D-ribofuranose 1-phosphate &alpha;-D-ribofuranose 1-phosphoric acid &alpha;-D-ribose-1P 1-O-Phosphono-D-ribofuranose A-D-Ribofuranose 1-(dihydrogen phosphate) a-D-Ribofuranose 1-(dihydrogen phosphoric acid) a-D-Ribofuranose 1-phosphate a-D-Ribofuranose 1-phosphoric acid A-D-Ribose 1-phosphate a-D-Ribose 1-phosphoric acid a-D-Ribose-1P Alpha-D-Ribofuranose 1-(dihydrogen phosphate) alpha-D-Ribofuranose 1-(dihydrogen phosphoric acid) Alpha-D-Ribofuranose 1-phosphate alpha-D-Ribofuranose 1-phosphoric acid Alpha-D-Ribose 1-phosphate alpha-D-Ribose 1-phosphoric acid Alpha-D-Ribose-1P D-Ribofuranose 1-(dihydrogen phosphate) D-Ribofuranose 1-(dihydrogen phosphoric acid) D-Ribofuranose 1-phosphate D-Ribofuranose 1-phosphoric acid D-Ribose-1-phosphate D-Ribose-1-phosphoric acid D-Ribose-1P Ribofuranose 1-phosphate Ribofuranose 1-phosphoric acid Ribose 1-phosphate Ribose 1-phosphoric acid Ribose-1-phosphate Ribose-1-phosphoric acid α-D-Ribofuranose 1-(dihydrogen phosphate) α-D-Ribofuranose 1-(dihydrogen phosphoric acid) α-D-Ribofuranose 1-phosphate α-D-Ribofuranose 1-phosphoric acid α-D-Ribose 1-phosphate α-D-Ribose 1-phosphoric acid α-D-Ribose-1P C5H11O8P 230.1098 230.01915384 {[(2R,3R,4S,5R)-3,4-dihydroxy-5-(hydroxymethyl)oxolan-2-yl]oxy}phosphonic acid ribose 1-phosphate 14075-00-4 OC[C@H]1O[C@H](OP(O)(O)=O)[C@H](O)[C@@H]1O InChI=1S/C5H11O8P/c6-1-2-3(7)4(8)5(12-2)13-14(9,10)11/h2-8H,1H2,(H2,9,10,11)/t2-,3-,4-,5-/m1/s1 YXJDFQJKERBOBM-TXICZTDVSA-N Solid Cytosol logp -2.04 ALOGPS logs -0.82 ALOGPS solubility 3.52e+01 g/l ALOGPS logp -2.4 ChemAxon pka_strongest_acidic 1.16 ChemAxon pka_strongest_basic -3 ChemAxon iupac {[(2R,3R,4S,5R)-3,4-dihydroxy-5-(hydroxymethyl)oxolan-2-yl]oxy}phosphonic acid ChemAxon average_mass 230.1098 ChemAxon mono_mass 230.01915384 ChemAxon smiles OC[C@H]1O[C@H](OP(O)(O)=O)[C@H](O)[C@@H]1O ChemAxon formula C5H11O8P ChemAxon inchi InChI=1S/C5H11O8P/c6-1-2-3(7)4(8)5(12-2)13-14(9,10)11/h2-8H,1H2,(H2,9,10,11)/t2-,3-,4-,5-/m1/s1 ChemAxon inchikey YXJDFQJKERBOBM-TXICZTDVSA-N ChemAxon polar_surface_area 136.68 ChemAxon refractivity 40.83 ChemAxon polarizability 18.17 ChemAxon rotatable_bond_count 3 ChemAxon acceptor_count 7 ChemAxon donor_count 5 ChemAxon physiological_charge -2 ChemAxon formal_charge 0 ChemAxon Pentose phosphate pathway ec00030 Purine metabolism ec00230 Pyrimidine metabolism The metabolism of pyrimidines begins with L-glutamine interacting with water molecule and a hydrogen carbonate through an ATP driven carbamoyl phosphate synthetase resulting in a hydrogen ion, an ADP, a phosphate, an L-glutamic acid and a carbamoyl phosphate. The latter compound interacts with an L-aspartic acid through a aspartate transcarbamylase resulting in a phosphate, a hydrogen ion and a N-carbamoyl-L-aspartate. The latter compound interacts with a hydrogen ion through a dihydroorotase resulting in the release of a water molecule and a 4,5-dihydroorotic acid. This compound interacts with an ubiquinone-1 through a dihydroorotate dehydrogenase, type 2 resulting in a release of an ubiquinol-1 and an orotic acid. The orotic acid then interacts with a phosphoribosyl pyrophosphate through a orotate phosphoribosyltransferase resulting in a pyrophosphate and an orotidylic acid. The latter compound then interacts with a hydrogen ion through an orotidine-5 '-phosphate decarboxylase, resulting in an release of carbon dioxide and an Uridine 5' monophosphate. The Uridine 5' monophosphate process to get phosphorylated by an ATP driven UMP kinase resulting in the release of an ADP and an Uridine 5--diphosphate. Uridine 5-diphosphate can be metabolized in multiple ways in order to produce a Deoxyuridine triphosphate. 1.-Uridine 5-diphosphate interacts with a reduced thioredoxin through a ribonucleoside diphosphate reductase 1 resulting in the release of a water molecule and an oxidized thioredoxin and an dUDP. The dUDP is then phosphorylated by an ATP through a nucleoside diphosphate kinase resulting in the release of an ADP and a DeoxyUridine triphosphate. 2.-Uridine 5-diphosphate interacts with a reduced NrdH glutaredoxin-like protein through a Ribonucleoside-diphosphate reductase 1 resulting in a release of a water molecule, an oxidized NrdH glutaredoxin-like protein and a dUDP. The dUDP is then phosphorylated by an ATP through a nucleoside diphosphate kinase resulting in the release of an ADP and a DeoxyUridine triphosphate. 3.-Uridine 5-diphosphate is phosphorylated by an ATP-driven nucleoside diphosphate kinase resulting in an ADP and an Uridinetriphosphate. The latter compound interacts with a reduced flavodoxin through ribonucleoside-triphosphate reductase resulting in the release of an oxidized flavodoxin, a water molecule and a Deoxyuridine triphosphate 4.-Uridine 5-diphosphate is phosphorylated by an ATP-driven nucleoside diphosphate kinase resulting in an ADP and an Uridinetriphosphate The uridine triphosphate interacts with a L-glutamine and a water molecule through an ATP driven CTP synthase resulting in an ADP, a phosphate, a hydrogen ion, an L-glutamic acid and a cytidine triphosphate. The cytidine triphosphate interacts with a reduced flavodoxin through a ribonucleoside-triphosphate reductase resulting in the release of a water molecule, an oxidized flavodoxin and a dCTP. The dCTP interacts with a water molecule and a hydrogen ion through a dCTP deaminase resulting in a release of an ammonium molecule and a Deoxyuridine triphosphate. 5.-Uridine 5-diphosphate is phosphorylated by an ATP-driven nucleoside diphosphate kinase resulting in an ADP and an Uridinetriphosphate The uridine triphosphate interacts with a L-glutamine and a water molecule through an ATP driven CTP synthase resulting in an ADP, a phosphate, a hydrogen ion, an L-glutamic acid and a cytidine triphosphate. The cytidine triphosphate then interacts spontaneously with a water molecule resulting in the release of a phosphate, a hydrogen ion and a CDP. The CDP then interacts with a reduced NrdH glutaredoxin-like protein through a ribonucleoside-diphosphate reductase 2 resulting in the release of a water molecule, an oxidized NrdH glutaredoxin-like protein and a dCDP. The dCDP is then phosphorylated through an ATP driven nucleoside diphosphate kinase resulting in an ADP and a dCTP. The dCTP interacts with a water molecule and a hydrogen ion through a dCTP deaminase resulting in a release of an ammonium molecule and a Deoxyuridine triphosphate. 6.-Uridine 5-diphosphate is phosphorylated by an ATP-driven nucleoside diphosphate kinase resulting in an ADP and an Uridinetriphosphate The uridine triphosphate interacts with a L-glutamine and a water molecule through an ATP driven CTP synthase resulting in an ADP, a phosphate, a hydrogen ion, an L-glutamic acid and a cytidine triphosphate. The cytidine triphosphate then interacts spontaneously with a water molecule resulting in the release of a phosphate, a hydrogen ion and a CDP. The CDP interacts with a reduced thioredoxin through a ribonucleoside diphosphate reductase 1 resulting in a release of a water molecule, an oxidized thioredoxin and a dCDP. The dCDP is then phosphorylated through an ATP driven nucleoside diphosphate kinase resulting in an ADP and a dCTP. The dCTP interacts with a water molecule and a hydrogen ion through a dCTP deaminase resulting in a release of an ammonium molecule and a Deoxyuridine triphosphate. The deoxyuridine triphosphate then interacts with a water molecule through a nucleoside triphosphate pyrophosphohydrolase resulting in a release of a hydrogen ion, a phosphate and a dUMP. The dUMP then interacts with a methenyltetrahydrofolate through a thymidylate synthase resulting in a dihydrofolic acid and a 5-thymidylic acid. Then 5-thymidylic acid is then phosphorylated through a nucleoside diphosphate kinase resulting in the release of an ADP and thymidine 5'-triphosphate. PW000942 ec00240 Metabolic Drug metabolism - other enzymes ec00983 Nicotinate and nicotinamide metabolism ec00760 Metabolic pathways eco01100 PRPP Biosynthesis The biosynthesis of phosphoribosyl pyrophosphate begins with a product of the pentose phosphate, D-ribose 5-phosphate interact with a phosphopentomutase resulting in a Ribose 1-phosphate or it can be phosphorylated through an ATP driven ribose-phosphate diphosphokinase resulting in a release of a hydrogen ion, an AMP and a phosphoribosyl pyrophosphate. The latter compound is then involved in the purine nucleotides de novo biosynthesis pathway. Ribose 1-phosphate can interact spontaneously with ATP resulting in a release of hydrogen ion, ADP and a ribose 1,5-biphosphate. The latter compound is then phosphorylated through a ribose 1,5-bisphosphokinase resulting in the release of ADP and phosphoribosyl pyrophosphate. The latter compound is then involved in the purine nucleotides de novo biosynthesis pathway. PW000909 Metabolic Pyrimidine ribonucleosides degradtion Cytidine and Uridine are transported through their corresponding nucleoside hydrogen symporters . Once cytidine is incorporated into the cytosol, it is deaminated through a reaction with water and a hydrogen ion through a cytidine deaminase resulting in the release of ammonium and uridine. Uridine is then lyase by a phosphate through a uridine phosphorylase resulting in the release of a uracil and a alpha-D-ribose-1-phosphate. This compound is then transformed into an isomer D-ribose 5-phosphate through a alpha-D-ribose 1,5-phosphomutase. This cumpound is then incorporated into the pentose phosphate pathway PW002024 Metabolic adenine and adenosine salvage I The salvage of adenine begins with adenine being transporter into the cytosol through a adeP hydrogen symporter. Once in the cytosol adenine is degraded by reacting with a ribose-1-phosphate through an adenosine phosphorylase resulting in the release of a phosphate and adenosine. Adenosine is then deaminated by reacting with water, a hydrogen ion and an adenosine deaminase resulting in the release of an ammonium and a inosine . Inosine then reacts with a phosphate through a inosine phosphorylase resulting in the release of a ribose 1-phosphate and a hypoxanthine. Hypoxanthine reacts with a PRPP through a hypoxanthine phosphoribosyltransferase resulting in the release of a pyrophosphate and a IMP molecule. PW002069 Metabolic adenine and adenosine salvage II The salvage of adenine begins with adenine being transporter into the cytosol through a adeP hydrogen symporter. Once in the cytosol adenine is degraded by reacting with a ribose-1-phosphate through an adenosine phosphorylase resulting in the release of a phosphate and adenosine. Adenosine is then deaminated by reacting with water, a hydrogen ion and an adenosine deaminase resulting in the release of an ammonium and a inosine . Inosine can then be phosphorylated through an ATP driven inosine kinase resulting in the release of an ADP, a hydrogen ion and a IMP PW002071 Metabolic guanine and guanosine salvage Guanosine can be converted into guanine through a phosphate driven guanosine phosphorylase resulting in the release of an alpha-D-ribose 1 phosphate and a guanine. This compound in turn reacts with a PRPP through a guanine phosphoribosyltransferase resulting in the release of a pyrophosphate and a GMP. Guanosine can also react with and ATP driven guanosine kinase resulting in the release of an ADP, s hydrogen ion and a GMP PW002074 Metabolic purine ribonucleosides degradation Purine ribonucleoside degradation leads to the production of alpha-D-ribose-1-phosphate. Xanthosine is transported into the cytosol through a xapB. Once in the cytosol xanthosine interacts with phosphate through a xanthosine phosphorylase resulting in the release of a xanthine and a alpha-D-ribose-1-phosphate. Adenosine is transported through a nupC or a nupG transporter, once inside the cytosol it can either react with a phosphate through a adenosine phosphorylase resultin in the release of a adenine and an alpha-D-ribose-1-phosphate. Adenosine reacts with water and hydrogen ion through a adenosine deaminase resulting in the release of ammonium and inosine. Inosine reacts with phosphate through a inosine phosphorylase resulting in the release of a hypoxanthine and an alpha-D-ribose-1-phosphate. Guanosine reacts with a phosphate through a guanosine phosphorylase resulting in the release of a guanine and a alpha-D-ribose-1-phosphate. PW002076 Metabolic adenosine nucleotides degradation The degradation of of adenosine nucleotides starts with AMP reacting with water through a nucleoside monophosphate phosphatase results in the release of phosphate and a adenosine. Adenosine reacts with water and hydrogen ion through an adenosine deaminase resulting in the release of ammonium and a inosine. Inosine reacts with phosphate through a inosine phosphorylase resulting in the release of an alpha-D-ribose-1-phosphate and an hypoxanthine. Hypoxanthine reacts with a water molecule and a NAD molecule through an hypoxanthine hydroxylase resulting in the release of an hydrogen ion, an NADH and a xanthine. Xanthine in turn is degraded by reacting with a water molecule and a NAD through xanthine NAD oxidoreductase resulting in the release of NADH, a hydrogen ion and urate. PW002091 Metabolic pyrimidine ribonucleosides degradation The degradation of pyrimidine ribonucleosides starts with either cytidine or uridine being transported into the cytosol. Cytidine is transported into the cytosol through an nupG transporter. Once inside the cytosol, it can be degraded into uridine by reacting with water and ahydrogen ion through a cytidine deaminase resulting in the release of ammonium and uridine. Uridine is transported into the cytosol through a nupG. Once in the cytosol , uridine can be degrade by reacting with phosphate through a uridine phosphorylase resulting in the release of an alpha-D-ribose-1-phosphate and a uracil. The alpha-D-ribose-1-phosphate reacts with an alpha-d-ribose 1,5-phosphomutase resulting in the release of a D-ribose 5-phosphate which can be incorporated into the pentose phosphate pathway. PW002104 Metabolic adenine and adenosine salvage III PWY-6609 adenine and adenosine salvage V PWY-6611 purine ribonucleosides degradation to ribose-1-phosphate PWY0-1296 adenosine nucleotides degradation II SALVADEHYPOX-PWY salvage pathways of pyrimidine ribonucleotides PWY0-163 pyrimidine ribonucleosides degradation I PWY0-1295 guanosine nucleotides degradation III PWY-6608 guanine and guanosine salvage I PWY-6620 xanthine and xanthosine salvage SALVPURINE2-PWY PRPP biosynthesis II PWY0-661 Specdb::CMs 3434 Specdb::CMs 38092 Specdb::CMs 136392 Specdb::CMs 144126 Specdb::NmrOneD 147880 Specdb::NmrOneD 147881 Specdb::NmrOneD 147882 Specdb::NmrOneD 147883 Specdb::NmrOneD 147884 Specdb::NmrOneD 147885 Specdb::NmrOneD 147886 Specdb::NmrOneD 147887 Specdb::NmrOneD 147888 Specdb::NmrOneD 147889 Specdb::NmrOneD 147890 Specdb::NmrOneD 147891 Specdb::NmrOneD 147892 Specdb::NmrOneD 147893 Specdb::NmrOneD 147894 Specdb::NmrOneD 147895 Specdb::NmrOneD 147896 Specdb::NmrOneD 147897 Specdb::NmrOneD 147898 Specdb::NmrOneD 147899 Specdb::MsMs 26912 Specdb::MsMs 26913 Specdb::MsMs 26914 Specdb::MsMs 33470 Specdb::MsMs 33471 Specdb::MsMs 33472 Specdb::MsMs 438394 Specdb::MsMs 438395 Specdb::MsMs 438396 Specdb::MsMs 438397 Specdb::MsMs 438398 Specdb::MsMs 2802613 Specdb::MsMs 2802614 Specdb::MsMs 2802615 Specdb::MsMs 2878880 Specdb::MsMs 2878881 Specdb::MsMs 2878882 HMDB01489 123732 388373 C00620 16300 RIBOSE-1P RDP Keseler, I. M., Collado-Vides, J., Santos-Zavaleta, A., Peralta-Gil, M., Gama-Castro, S., Muniz-Rascado, L., Bonavides-Martinez, C., Paley, S., Krummenacker, M., Altman, T., Kaipa, P., Spaulding, A., Pacheco, J., Latendresse, M., Fulcher, C., Sarker, M., Shearer, A. G., Mackie, A., Paulsen, I., Gunsalus, R. P., Karp, P. D. (2011). "EcoCyc: a comprehensive database of Escherichia coli biology." Nucleic Acids Res 39:D583-D590. 21097882 Kanehisa, M., Goto, S., Sato, Y., Furumichi, M., Tanabe, M. (2012). "KEGG for integration and interpretation of large-scale molecular data sets." Nucleic Acids Res 40:D109-D114. 22080510 van der Werf, M. J., Overkamp, K. M., Muilwijk, B., Coulier, L., Hankemeier, T. (2007). "Microbial metabolomics: toward a platform with full metabolome coverage." Anal Biochem 370:17-25. 17765195 Winder, C. L., Dunn, W. B., Schuler, S., Broadhurst, D., Jarvis, R., Stephens, G. M., Goodacre, R. (2008). "Global metabolic profiling of Escherichia coli cultures: an evaluation of methods for quenching and extraction of intracellular metabolites." Anal Chem 80:2939-2948. 18331064 Bennett, B. D., Kimball, E. H., Gao, M., Osterhout, R., Van Dien, S. J., Rabinowitz, J. D. (2009). "Absolute metabolite concentrations and implied enzyme active site occupancy in Escherichia coli." Nat Chem Biol 5:593-599. 19561621 Giorgelli, F., Bottai, C., Mascia, L., Scolozzi, C., Camici, M., Ipata, P. L. (1997). "Recycling of alpha-D-ribose 1-phosphate for nucleoside interconversion." Biochim Biophys Acta 1335:6-22. 9133638 Nakayama Y, Kinoshita A, Tomita M: Dynamic simulation of red blood cell metabolism and its application to the analysis of a pathological condition. Theor Biol Med Model. 2005 May 9;2(1):18. 15882454 Tochikura, Tatsurokuro; Sakai, Takuo; Ogata, Koichi. Ribose 1-phosphate production by fermentation. Jpn. Tokkyo Koho (1969), 3 pp. Phosphopentomutase P0A6K6 DEOB_ECOLI deoB http://ecmdb.ca/proteins/P0A6K6.xml Purine nucleoside phosphorylase deoD-type P0ABP8 DEOD_ECOLI deoD http://ecmdb.ca/proteins/P0ABP8.xml Uridine phosphorylase P12758 UDP_ECOLI udp http://ecmdb.ca/proteins/P12758.xml Phosphoglucomutase P36938 PGM_ECOLI pgm http://ecmdb.ca/proteins/P36938.xml Xanthosine phosphorylase P45563 XAPA_ECOLI xapA http://ecmdb.ca/proteins/P45563.xml Uncharacterized protein yhfW P45549 YHFW_ECOLI yhfW http://ecmdb.ca/proteins/P45549.xml Guanosine + Phosphate <> Guanine + Ribose-1-phosphate RXN0-5199 Inosine + Phosphate <> Hypoxanthine + Ribose-1-phosphate INOPHOSPHOR-RXN Ribose-1-phosphate <> D-Ribose-5-phosphate PPENTOMUT-RXN Phosphate + Xanthosine <> Ribose-1-phosphate + Xanthine XANTHOSINEPHOSPHORY-RXN Phosphate + Uridine <> Ribose-1-phosphate + Uracil URPHOS-RXN Adenosine + Phosphate <> Adenine + Ribose-1-phosphate ADENPHOSPHOR-RXN Ribose-1-phosphate + Adenosine triphosphate > Hydrogen ion + Ribose 1,5-bisphosphate + ADP RXN0-1402 a purine ribonucleoside + Phosphate <> a purine base + Ribose-1-phosphate PNP-RXN Xanthosine + Phosphate > Ribose-1-phosphate + Xanthine XANTHOSINEPHOSPHORY-RXN Ribose-1-phosphate > D-Ribose-5-phosphate Purine nucleoside + Inorganic phosphate > Purine + Ribose-1-phosphate Uridine + Inorganic phosphate > Uracil + Ribose-1-phosphate Uridine + Phosphate <> Uracil + alpha-D-Ribose 1-phosphate + Ribose-1-phosphate R01876 alpha-D-Ribose 1-phosphate + Ribose-1-phosphate <> D-Ribose-5-phosphate R01057 Purine nucleoside + Phosphate + Purine deoxyribonucleoside <> Purine + Ribose-1-phosphate + Deoxyribose 1-phosphate R08368 D-Ribose-5-phosphate > Ribose-1-phosphate PW_R003407 Uridine + Phosphate > Uracil + Ribose-1-phosphate PW_R005898 Adenine + Ribose-1-phosphate > Phosphate + Adenosine PW_R006047 Inosine + Phosphate > Ribose-1-phosphate + Hypoxanthine PW_R006050 Guanosine + Phosphate > Ribose-1-phosphate + Guanine PW_R006058 Adenosine + Phosphate > Adenine + Ribose-1-phosphate PW_R006066 Gutnick minimal complete medium (4.7 g/L KH2PO4; 13.5 g/L K2HPO4; 1 g/L K2SO4; 0.1 g/L MgSO4-7H2O; 10 mM NH4Cl) with 4 g/L glycerol Shake flask and filter culture 1020.0 uM 0.0 37 oC K12 NCM3722 Mid-Log Phase 4080000 0 Bennett, B. D., Kimball, E. H., Gao, M., Osterhout, R., Van Dien, S. J., Rabinowitz, J. D. (2009). "Absolute metabolite concentrations and implied enzyme active site occupancy in Escherichia coli." Nat Chem Biol 5:593-599. 19561621 Gutnick minimal complete medium (4.7 g/L KH2PO4; 13.5 g/L K2HPO4; 1 g/L K2SO4; 0.1 g/L MgSO4-7H2O; 10 mM NH4Cl) with 4 g/L acetate Shake flask and filter culture 686.0 uM 0.0 37 oC K12 NCM3722 Mid-Log Phase 2744000 0 Bennett, B. D., Kimball, E. H., Gao, M., Osterhout, R., Van Dien, S. J., Rabinowitz, J. D. (2009). "Absolute metabolite concentrations and implied enzyme active site occupancy in Escherichia coli." Nat Chem Biol 5:593-599. 19561621 Gutnick minimal complete medium (4.7 g/L KH2PO4; 13.5 g/L K2HPO4; 1 g/L K2SO4; 0.1 g/L MgSO4-7H2O; 10 mM NH4Cl) with 4 g/L glucose Shake flask and filter culture 1320.0 uM 0.0 37 oC K12 NCM3722 Mid-Log Phase 5280000 0 Bennett, B. D., Kimball, E. H., Gao, M., Osterhout, R., Van Dien, S. J., Rabinowitz, J. D. (2009). "Absolute metabolite concentrations and implied enzyme active site occupancy in Escherichia coli." Nat Chem Biol 5:593-599. 19561621