2.02012-05-31 14:29:43 -06002015-06-03 17:19:24 -0600ECMDB20142M2MDB000990D-GalactosamineD-galactosamine is a member of the chemical class known as Hexoses. These are monosaccharides in which the sugar unit is a hexose. D-Galactosamine is an amino sugar with unique hepatotoxic properties in animals. (PMID 6338507)2-Amino-2-deoxy-D-galactopyranose2-Amino-2-deoxy-D-galactoseChondrosamineD-2-Amino-2-deoxygalactoseD-ChondrosamineD-galactosamineGalactosamineC6H13NO5179.1711179.079372531(3R,4R,5R,6R)-3-amino-6-(hydroxymethyl)oxane-2,4,5-triolgalactosamine7535-00-4N[C@H]1C(O)O[C@H](CO)[C@H](O)[C@@H]1OInChI=1S/C6H13NO5/c7-3-5(10)4(9)2(1-8)12-6(3)11/h2-6,8-11H,1,7H2/t2-,3-,4+,5-,6?/m1/s1MSWZFWKMSRAUBD-GASJEMHNSA-NCytoplasmPeriplasmlogp-2.73logs0.49solubility5.51e+02 g/llogp-3pka_strongest_acidic11.73pka_strongest_basic8.23iupac(3R,4R,5R,6R)-3-amino-6-(hydroxymethyl)oxane-2,4,5-triolaverage_mass179.1711mono_mass179.079372531smilesN[C@H]1C(O)O[C@H](CO)[C@H](O)[C@@H]1OformulaC6H13NO5inchiInChI=1S/C6H13NO5/c7-3-5(10)4(9)2(1-8)12-6(3)11/h2-6,8-11H,1,7H2/t2-,3-,4+,5-,6?/m1/s1inchikeyMSWZFWKMSRAUBD-GASJEMHNSA-Npolar_surface_area116.17refractivity37.58polarizability16.72rotatable_bond_count1acceptor_count6donor_count5physiological_charge1formal_charge0Galactose metabolismGalactose 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
PW000821ec00052MetabolicPhosphotransferase system (PTS)ec02060Specdb::CMs1085168Specdb::NmrOneD265348Specdb::NmrOneD265349Specdb::NmrOneD265350Specdb::NmrOneD265351Specdb::NmrOneD265352Specdb::NmrOneD265353Specdb::NmrOneD265354Specdb::NmrOneD265355Specdb::NmrOneD265356Specdb::NmrOneD265357Specdb::NmrOneD265358Specdb::NmrOneD265359Specdb::NmrOneD265360Specdb::NmrOneD265361Specdb::NmrOneD265362Specdb::NmrOneD265363Specdb::NmrOneD265364Specdb::NmrOneD265365Specdb::NmrOneD265366Specdb::NmrOneD265367Specdb::MsMs23993Specdb::MsMs23994Specdb::MsMs23995Specdb::MsMs30791Specdb::MsMs30792Specdb::MsMs307932415422576C0226228328GALACTOSAMINEKeseler, 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-D590.21097882Kanehisa, 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-D114.22080510Camara, D. S., Caruana, J. A. Jr, Schwartz, K. A., Montes, M., Nolan, J. P. (1983). "D-Galactosamine liver injury: absorption of endotoxin and protective effect of small bowel and colon resection in rabbits." Proc Soc Exp Biol Med 172:255-259.6338507N-acetylgalactosamine-specific phosphotransferase enzyme IIB component 1P42909PTPB1_ECOLIagaBhttp://ecmdb.ca/proteins/P42909.xmlN-acetylgalactosamine permease IIC component 1P42910PTPC1_ECOLIagaChttp://ecmdb.ca/proteins/P42910.xmlN-acetylgalactosamine permease IID componentP42911PTPD_ECOLIagaDhttp://ecmdb.ca/proteins/P42911.xmlN-acetylgalactosamine permease IIC component 1P42910PTPC1_ECOLIagaChttp://ecmdb.ca/proteins/P42910.xmlN-acetylgalactosamine permease IID componentP42911PTPD_ECOLIagaDhttp://ecmdb.ca/proteins/P42911.xmlD-Galactosamine + Protein N(pi)-phospho-L-histidine <> D-Galactosamine 6-phosphate + Protein histidineR08367