Target type: biologicalprocess
The chemical reactions and pathways resulting in the breakdown of galactose, the aldohexose galacto-hexose. [ISBN:0198506732]
Galactose catabolism is the metabolic pathway that breaks down galactose, a simple sugar found in milk and other dairy products, into glucose, a primary energy source for the body. This process occurs primarily in the liver and involves a series of enzymatic steps.
1. **Galactose Kinase:** The first step in galactose metabolism is the phosphorylation of galactose by galactose kinase, using ATP as a phosphate donor. This reaction produces galactose-1-phosphate.
2. **Galactose-1-Phosphate Uridyltransferase:** Galactose-1-phosphate then reacts with UDP-glucose, catalyzed by galactose-1-phosphate uridyltransferase, to form UDP-galactose and glucose-1-phosphate. This is a key step as it converts galactose into a form that can be utilized in the body.
3. **UDP-Galactose 4-Epimerase:** UDP-galactose is converted to UDP-glucose by UDP-galactose 4-epimerase, an enzyme that catalyzes the epimerization of the hydroxyl group at carbon 4. This reaction completes the conversion of galactose into a form that can be used in glycolysis or glycogen synthesis.
4. **Glucose-6-Phosphate:** The glucose-1-phosphate produced in step 2 is converted to glucose-6-phosphate by phosphoglucomutase, allowing it to enter the glycolytic pathway for energy production or to be stored as glycogen.
Galactose metabolism is essential for the proper utilization of galactose in the body. Deficiencies in any of the enzymes involved in this process can lead to galactosemia, a genetic disorder that can cause various health issues. The regulation of galactose metabolism is tightly controlled to maintain glucose homeostasis and prevent toxic buildup of galactose derivatives.'
"
| Protein | Definition | Taxonomy |
|---|---|---|
| UDP-glucose 4-epimerase | A UDP-glucose 4-epimerase that is encoded in the genome of human. [PRO:DNx, UniProtKB:Q14376] | Homo sapiens (human) |
| Galactokinase | A galactokinase that is encoded in the genome of human. [PRO:DNx, UniProtKB:P51570] | Homo sapiens (human) |
| Beta-galactosidase | A eukaryotic-type beta-galactosidase that is encoded in the genome of human. [PRO:DNx, UniProtKB:P16278] | Homo sapiens (human) |
| Compound | Definition | Classes | Roles |
|---|---|---|---|
| ebselen | ebselen : A benzoselenazole that is 1,2-benzoselenazol-3-one carrying an additional phenyl substituent at position 2. Acts as a mimic of glutathione peroxidase. | benzoselenazole | anti-inflammatory drug; antibacterial agent; anticoronaviral agent; antifungal agent; antineoplastic agent; antioxidant; apoptosis inducer; EC 1.13.11.33 (arachidonate 15-lipoxygenase) inhibitor; EC 1.13.11.34 (arachidonate 5-lipoxygenase) inhibitor; EC 1.3.1.8 [acyl-CoA dehydrogenase (NADP(+))] inhibitor; EC 1.8.1.12 (trypanothione-disulfide reductase) inhibitor; EC 2.5.1.7 (UDP-N-acetylglucosamine 1-carboxyvinyltransferase) inhibitor; EC 2.7.10.1 (receptor protein-tyrosine kinase) inhibitor; EC 3.1.3.25 (inositol-phosphate phosphatase) inhibitor; EC 3.4.22.69 (SARS coronavirus main proteinase) inhibitor; EC 3.5.4.1 (cytosine deaminase) inhibitor; EC 5.1.3.2 (UDP-glucose 4-epimerase) inhibitor; enzyme mimic; ferroptosis inhibitor; genotoxin; hepatoprotective agent; neuroprotective agent; radical scavenger |
| ethacrynic acid | etacrynic acid : An aromatic ether that is phenoxyacetic acid in which the phenyl ring is substituted by chlorines at positions 2 and 3, and by a 2-methylidenebutanoyl group at position 4. It is a loop diuretic used to treat high blood pressure resulting from diseases such as congestive heart failure, liver failure, and kidney failure. It is also a glutathione S-transferase (EC 2.5.1.18) inhibitor. Ethacrynic Acid: A compound that inhibits symport of sodium, potassium, and chloride primarily in the ascending limb of Henle, but also in the proximal and distal tubules. This pharmacological action results in excretion of these ions, increased urinary output, and reduction in extracellular fluid. This compound has been classified as a loop or high ceiling diuretic. | aromatic ether; aromatic ketone; dichlorobenzene; monocarboxylic acid | EC 2.5.1.18 (glutathione transferase) inhibitor; ion transport inhibitor; loop diuretic |
| haloprogin | haloprogin: minor descriptor (73-86); on-line & INDEX MEDICUS search PHENYL ETHERS (73-86) | aromatic ether | |
| galactose | galactopyranose : The pyranose form of galactose. | D-galactose; galactopyranose | Escherichia coli metabolite; mouse metabolite |
| congo red | Congo Red : An indicator dye that is blue-violet at pH 3.0 and red at pH 5.0. Congo Red: An acid dye used in testing for hydrochloric acid in gastric contents. It is also used histologically to test for AMYLOIDOSIS. | bis(azo) compound | |
| iodophthalein | |||
| migalastat | migalastat: a potent inhibitor of glycolipid biosynthesis | piperidines | |
| isofagomine | piperidines | ||
| diethylstilbestrol | diethylstilbestrol : An olefinic compound that is trans-hex-3-ene in which the hydrogens at positions 3 and 4 have been replaced by p-hydroxyphenyl groups. Diethylstilbestrol: A synthetic nonsteroidal estrogen used in the treatment of menopausal and postmenopausal disorders. It was also used formerly as a growth promoter in animals. According to the Fourth Annual Report on Carcinogens (NTP 85-002, 1985), diethylstilbestrol has been listed as a known carcinogen. (Merck, 11th ed) | olefinic compound; polyphenol | antifungal agent; antineoplastic agent; autophagy inducer; calcium channel blocker; carcinogenic agent; EC 1.1.1.146 (11beta-hydroxysteroid dehydrogenase) inhibitor; EC 3.6.3.10 (H(+)/K(+)-exchanging ATPase) inhibitor; endocrine disruptor; xenoestrogen |
| 2-(1,3-benzoxazol-2-ylamino)-5-spiro[1,6,7,8-tetrahydroquinazoline-4,1'-cyclopentane]one | quinazolines | ||
| psammaplin a | psammaplin A: isolated from marine sponges Poecillastra and Jaspis; structure in second source |