2.0 2012-05-31 10:27:25 -0600 2015-09-13 15:15:19 -0600 ECMDB00565 M2MDB000150 Galactonic acid Galactonic acid is a member of the chemical class known as Sugar Acids and Derivatives. These are compounds containing a saccharide unit which bears a carboxylic acid group. D-Galacturonic acid is a sugar acid, an oxidized form of D-galactose. It is the main component of pectin, in which it exists as the polymer polygalacturonic acid. It has an aldehyde group at C1 and a carboxylic acid group at C6. Other oxidized forms of D-galactose are D-galactonic acid (carboxylic group at C1) and meso-galactaric acid (mucic acid) (carboxylic groups at C1 and C6). It is also a uronic acid or hexuronic acid. Naturally occurring uronic acids are D-glucuronic acid, D-galacturonic acid, L-iduronic acid and D-mannuronic acid. (WikiPedia) Galactonate Galactonic acid C6H12O7 196.1553 196.058302738 (2R,3S,4S,5R)-2,3,4,5,6-pentahydroxyhexanoic acid galactonic acid 13382-27-9 OC[C@@H](O)[C@H](O)[C@H](O)[C@@H](O)C(O)=O InChI=1S/C6H12O7/c7-1-2(8)3(9)4(10)5(11)6(12)13/h2-5,7-11H,1H2,(H,12,13)/t2-,3+,4+,5-/m1/s1 RGHNJXZEOKUKBD-MGCNEYSASA-N Solid Cytosol Extra-organism Periplasm logp -2.57 ALOGPS logs -0.09 ALOGPS solubility 1.59e+02 g/l ALOGPS melting_point 133-136 oC logp -3.4 ChemAxon pka_strongest_acidic 3.39 ChemAxon pka_strongest_basic -3 ChemAxon iupac (2R,3S,4S,5R)-2,3,4,5,6-pentahydroxyhexanoic acid ChemAxon average_mass 196.1553 ChemAxon mono_mass 196.058302738 ChemAxon smiles OC[C@@H](O)[C@H](O)[C@H](O)[C@@H](O)C(O)=O ChemAxon formula C6H12O7 ChemAxon inchi InChI=1S/C6H12O7/c7-1-2(8)3(9)4(10)5(11)6(12)13/h2-5,7-11H,1H2,(H,12,13)/t2-,3+,4+,5-/m1/s1 ChemAxon inchikey RGHNJXZEOKUKBD-MGCNEYSASA-N ChemAxon polar_surface_area 138.45 ChemAxon refractivity 38.27 ChemAxon polarizability 17.07 ChemAxon rotatable_bond_count 5 ChemAxon acceptor_count 7 ChemAxon donor_count 6 ChemAxon physiological_charge -1 ChemAxon formal_charge 0 ChemAxon Galactose metabolism Galactose can be synthesized through two pathways: melibiose degradation involving an alpha galactosidase and lactose degradation involving a beta galactosidase. Melibiose is first transported inside the cell through the melibiose:Li+/Na+/H+ symporter. Once inside the cell, melibiose is degraded through alpha galactosidase into an alpha-D-galactose and a beta-D-glucose. The beta-D-glucose is phosphorylated by a glucokinase to produce a beta-D-glucose-6-phosphate which can spontaneously be turned into a alpha D glucose 6 phosphate. This alpha D-glucose-6-phosphate is metabolized into a glucose -1-phosphate through a phosphoglucomutase-1. The glucose -1-phosphate is transformed into a uridine diphosphate glucose through UTP--glucose-1-phosphate uridylyltransferase. The product, uridine diphosphate glucose, can undergo a reversible reaction in which it can be turned into uridine diphosphategalactose through an UDP-glucose 4-epimerase. Galactose can also be produced by lactose degradation involving a lactose permease to uptake lactose from the environment and a beta-galactosidase to turn lactose into Beta-D-galactose. Beta-D-galactose can also be uptaken from the environment through a galactose proton symporter. Galactose is degraded through the following process: Beta-D-galactose is introduced into the cytoplasm through a galactose proton symporter, or it can be synthesized from an alpha lactose that is introduced into the cytoplasm through a lactose permease. Alpha lactose interacts with water through a beta-galactosidase resulting in a beta-D-glucose and beta-D-galactose. Beta-D-galactose is isomerized into D-galactose. D-Galactose undergoes phosphorylation through a galactokinase, hence producing galactose 1 phosphate. On the other side of the pathway, a gluose-1-phosphate (product of the interaction of alpha-D-glucose 6-phosphate with a phosphoglucomutase resulting in a alpha-D-glucose-1-phosphate, an isomer of Glucose 1-phosphate, or an isomer of Beta-D-glucose 1-phosphate) interacts with UTP and a hydrogen ion in order to produce a uridine diphosphate glucose. This is followed by the interaction of galactose-1-phosphate with an established amount of uridine diphosphate glucose through a galactose-1-phosphate uridylyltransferase, which in turn output a glucose-1-phosphate and a uridine diphosphate galactose. The glucose -1-phosphate is transformed into a uridine diphosphate glucose through UTP--glucose-1-phosphate uridylyltransferase. The product, uridine diphosphate glucose, can undergo a reversible reaction in which it can be turned into uridine diphosphategalactose through an UDP-glucose 4-epimerase, and so the cycle can keep going as long as more lactose or galactose is imported into the cell PW000821 ec00052 Metabolic Microbial metabolism in diverse environments ec01120 Metabolic pathways eco01100 Galactitol and galactonate degradation D-galactonate can serve as the sole source of carbon and energy for E. coli . The initial step, after the transport of galactonic acid into the cell is the degradation of D-galactonate is dehydration to 2-dehydro-3-deoxy-D-galactonate by D-galactonate dehydratase. Subsequent phosphorylation by 2-dehydro-3-deoxygalactonate kinase and aldol cleavage by 2-oxo-3-deoxygalactonate 6-phosphate aldolase produce pyruvate and D-glyceraldehyde-3-phosphate, which enter central metabolism. Galactitol can also be utilized by E. coli K-12 as a total source of carbon and energy. Each enters the cell via a specific phosphotransferase system, so the first intracellular species is D-galactitol-1-phosphate or D-galactitol-6-phosphate, which are identical. This sugar alcohol phosphate becomes the substrate for a dehydrogenase that oxidizes its 2-alcohol group to a keto group. Galactitol-1-phosphate, the product of the dehydrogenation is tagatose-6-phosphate, which becomes the substrate of a kinase and subsequently an aldolase (in a pair of reactions that parallel those of glycolysis) before it is converted into intermediates (D-glyceraldehde-3-phosphate and dihydroxy-acetone-phosphate) of glycolysis. PW000820 Metabolic inner membrane transport list of inner membrane transport complexes, transporting compounds from the periplasmic space to the cytosol This pathway should be updated regularly with the new inner membrae transports added PW000786 Metabolic Specdb::CMs 1712 Specdb::CMs 10774 Specdb::CMs 31168 Specdb::CMs 32019 Specdb::CMs 37626 Specdb::CMs 146713 Specdb::CMs 147076 Specdb::CMs 279530 Specdb::CMs 1065921 Specdb::CMs 1065923 Specdb::CMs 1065925 Specdb::CMs 1065927 Specdb::CMs 1065928 Specdb::CMs 1065930 Specdb::CMs 1065932 Specdb::CMs 1065934 Specdb::CMs 1065935 Specdb::CMs 1065937 Specdb::CMs 1065939 Specdb::CMs 1065941 Specdb::CMs 1065943 Specdb::CMs 1065945 Specdb::CMs 1065947 Specdb::CMs 1065949 Specdb::CMs 1065950 Specdb::NmrOneD 1422 Specdb::NmrOneD 144390 Specdb::NmrOneD 144391 Specdb::NmrOneD 144392 Specdb::NmrOneD 144393 Specdb::NmrOneD 144394 Specdb::NmrOneD 144395 Specdb::NmrOneD 144396 Specdb::NmrOneD 144397 Specdb::NmrOneD 144398 Specdb::NmrOneD 144399 Specdb::NmrOneD 144400 Specdb::NmrOneD 144401 Specdb::NmrOneD 144402 Specdb::NmrOneD 144403 Specdb::NmrOneD 144404 Specdb::NmrOneD 144405 Specdb::NmrOneD 144406 Specdb::NmrOneD 144407 Specdb::NmrOneD 144408 Specdb::NmrOneD 144409 Specdb::NmrOneD 166326 Specdb::MsMs 788 Specdb::MsMs 789 Specdb::MsMs 790 Specdb::MsMs 289720 Specdb::MsMs 289721 Specdb::MsMs 289722 Specdb::MsMs 329227 Specdb::MsMs 329228 Specdb::MsMs 329229 Specdb::MsMs 2394628 Specdb::MsMs 2394629 Specdb::MsMs 2394630 Specdb::MsMs 2571830 Specdb::MsMs 2571831 Specdb::MsMs 2571832 Specdb::NmrTwoD 1367 HMDB00565 114198 C00880 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 Shoemaker JD, Elliott WH: Automated screening of urine samples for carbohydrates, organic and amino acids after treatment with urease. J Chromatogr. 1991 Jan 2;562(1-2):125-38. 2026685 Shinka T, Inoue Y, Peng H, Zhen-Wei X, Ose M, Kuhara T: Urine screening of five-day-old newborns: metabolic profiling of neonatal galactosuria. J Chromatogr B Biomed Sci Appl. 1999 Sep 24;732(2):469-77. 10517369 Yager CT, Chen J, Reynolds R, Segal S: Galactitol and galactonate in red blood cells of galactosemic patients. Mol Genet Metab. 2003 Nov;80(3):283-9. 14680973 Levene, P. A.; Simms, H. S. Lactone formation mono- and dicarboxylic sugar acids. Journal of Biological Chemistry (1925), 65 31-47. http://hmdb.ca/system/metabolites/msds/000/000/484/original/HMDB00565.pdf?1358463429 D-galactonate dehydratase Q6BF17 DGOD_ECOLI dgoD http://ecmdb.ca/proteins/Q6BF17.xml D-galactonate transporter P0AA76 DGOT_ECOLI dgoT http://ecmdb.ca/proteins/P0AA76.xml Outer membrane protein N P77747 OMPN_ECOLI ompN http://ecmdb.ca/proteins/P77747.xml Outer membrane pore protein E P02932 PHOE_ECOLI phoE http://ecmdb.ca/proteins/P02932.xml Outer membrane protein F P02931 OMPF_ECOLI ompF http://ecmdb.ca/proteins/P02931.xml Outer membrane protein C P06996 OMPC_ECOLI ompC http://ecmdb.ca/proteins/P06996.xml Galactonic acid <> 2-Dehydro-3-deoxy-D-galactonate + Water R03033 Galactonic acid > 2-Dehydro-3-deoxy-D-galactonate + Water Galactonic acid + Galactonic acid > Water + 2-dehydro-3-deoxy-D-galactonate + 2-Dehydro-3-deoxy-D-galactonate PW_R002940