epimerase


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epimerase

 [ĕ-pim´er-āse]
an isomerase enzyme that catalyzes a change in asymmetric groups in substrates (epimers) that have more than one center of asymmetry.

e·pim·er·ase

(ĕpim'ĕr-ās),
A class of enzymes catalyzing epimeric changes.

e·pim·er·ase

(ep'i-mĕr-ās)
[EC 5.1] A class of enzymes catalyzing epimeric changes.
References in periodicals archive ?
LDHA, lactate dehydrogenase A; LDHB, lactate dehydrogenase B; PDHA1, pyruvate dehydrogenase (lipoamide) alpha 1; DLAT, dihydrolipoamide S-cetyltransferase; DLD, dihydrolipoamide dehydrogenase; GK, glycerol kinase; GPD1, glycerol-3-phosphate dehydrogenase 1; GPD2, glycerol -3-phosphate dehydrogenase 2; ACSS3, acyl CoA synthetase short chain family member 3; PCCA, propionyl CoA carboxylase alpha; PCCB, propionyl CoA carboxylase beta; MCEE, methylmalonyl CoA epimerase; MUT, methylmalonyl CoA mutase.
Namely, it is still unclear if insulin resistance depends (at least in part) on a reduced content of membrane-bound IPGs, on a primary defect in IPG release, or if impaired epimerase activation downstream of insulin stimulation would ultimately lead to reduced DCIns intracellular availability.
An alteration of the M- to G-block proportion or an enrichment of polymer backbone in M-, G-, or MG-blocks is being practiced by modification through enzymatic epimerisation catalysed by mannuronan C-5 epimerases. This enzyme, isolated from the soil bacterium Azotobacter vinelandii and expressed in Escherichia coli, converts mannuronic acid residues into guluronic acid residues in the polymer backbone without breaking of the glycosidic bond [87, 115, 116].
du Pont de Nemours and Company (Wilmington, DE) has patented an isolated nucleic acid fragment encoding a plant enzyme that catalyze steps in the biosynthesis of lysine, threonine, methionine, cysteine and isoleucine from aspartate, the enzyme a member selected from the group consisting of: dihydrodipicolinate reductase, diaminopimelate epimerase, threonine synthase, threonine deaminase and S-adenosylmethionine synthetase.
Galactose is then further metabolized and is converted to glucose with the help of three enzymes present on the red blood cells: galactokinase, 1-phosphate uridyl transferase, and uridine diphosphoglucose 4 epimerase. Figure 1 is a diagram of the metabolic pathway.
In MDM, IFN-[alpha] stimulation was associated with a downregulation of multiple genes associated with branched-chain amino acid catabolism including branched-chain aminotransferase 2 (BCAT2), isovaleryl-CoA dehydrogenase (IVD), hydroxyacyl-CoA dehydrogenase (HADH), and methylmalonyl-CoA epimerase (MCEE).
According to DCI ovary paradox theory, an increase of epimerase function in the ovaries causes an increase of DCI level associated with a local MYO deficiency and poor oocyte quality [13] with a negative effect in FSH stimulation and in ovulation [14].
Target genes for detecting GIT microbiota's role metagenome in chicken metabolism Name Metabolism Function (protein) Glucoside hydrolase Carbohydrate Hydrolysis of carbohydrate Polysaccharide lyase Carbohydrate esterase Galactose transport protein Glucosamine-6-phosphate deaminase Methylmalonyl decarboxylase Fatty acids Propionate production Butyryl-CoA:acetate-CoA Butyrate production transferase 3-hydroxybutyryl-CoA Butyrate fermentation dehydrolase Acetate kinase Acetate fermentation Phosphate acetyltransferase Acetate fermentation Methylmalonyl-CoA epimerase Propionate production Dipeptidyl aminopeptidase Nitrogen Protein hydrolysis GIT, gastrointestinal tract.
Enzyme activity appears to be unidirectional and dependent on the presence of hydroxyl groups at C-1 or C-25, independent of cytochrome P450 enzymes (CYP 24, 27A1, and 27B1) and 3([alpha],[beta])-hydroxysteroid epimerase (31).
On the contrary, an epimerase activity was found in particulate enzymic preparation isolated from pine cambial and xylem cells which leads to the synthesis of glucomannans using only GDP-mannose as substrate [27].
Molecular characterization of a first human 3(alpha [right arrow] beta)-hydroxysteroid epimerase. J Biol Chem 275:29452-29457.
It is essential to highlight that myoinositol, the most represented and important stereoisomeric form of inositol, stands out for its key roles as leading molecule in some physiological areas, whereas different integrative functions are carried out by D-chiroinositol, synthetized from myoinositol under the enzymatic control of an epimerase. To get straight to the point, whereas the activation of glucose transporters and glucose utilization take place under the regulation of myoinositol, glycogen synthesis is mainly controlled by D-chiroinositol.