All articles starting with G
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Glucoamylase
Glucoamylase (amyloglucosidase, γ-amylase, EC 3.2.1.3) is an exo-acting GH15 inverting enzyme releasing β-glucose from starch α-1,4 and α-1,6 bonds, used industrially for saccharification to glucose syrups and ethanol.
Glucocerebroside
Glucocerebroside, also called glucosylceramide, is a glycosphingolipid consisting of a ceramide backbone with a glucose attached; it accumulates in Gaucher disease when glucocerebrosidase is deficient.
Glucocorticoid
Glucocorticoids are adrenal steroid hormones, chiefly cortisol, and synthetic drugs like prednisone and dexamethasone that act via the glucocorticoid receptor; cortisone's 1948 rheumatoid arthritis trial won Kendall, Hench, and Reichstein the 1950 Nobel Prize.
Glucocorticoid receptor
Glucocorticoid receptor (GR, NR3C1), a ligand-activated nuclear receptor for cortisol; three-domain structure, multiple splice isoforms, regulates up to 20% of the genome via GREs, nGREs, and NF-κB/AP-1 transrepression; target of selective modulators.
Glucocorticoid therapy
Glucocorticoid therapy is treatment with synthetic analogs of cortisol, used to suppress inflammation and immune activity in inflammatory, autoimmune, and allergic diseases or to replace cortisol in adrenal insufficiency.
Glucocorticoid-induced hypertension
Glucocorticoid-induced hypertension is blood pressure elevation caused by excess glucocorticoid hormones, from corticosteroid therapy or cortisol overproduction in Cushing's syndrome, affecting up to 85% of Cushing patients.
Glucokinase
Glucokinase (GCK, hexokinase IV) is a monomeric 52 kDa enzyme phosphorylating glucose, serving as the glucose sensor in pancreatic beta cells and liver, with sigmoidal kinetics (Hill ~1.7), GCKR regulation, GCK-MODY, and the activator drug dorzagliatin.
Glucolight trial
Glucolight (Babyglucolight, NCT04347590) is a Padua randomized trial testing continuous glucose monitoring with a PID algorithm against blinded CGM in preterm infants ≤32 weeks, measuring hemodynamically significant hypoglycemia via diffuse optical tomography.
Glucomannan
Glucomannan (konjac glucomannan, KGM, E425) is a highly viscous soluble fiber from Amorphophallus konjac, used for cholesterol, weight, and constipation; requires water to avoid obstruction.
Gluconacetobacter xylinus
Gluconacetobacter xylinus, now Komagataeibacter xylinus (formerly Acetobacter xylinum), is an aerobic acetic acid bacterium, described by Brown in 1886, that forms a pure cellulose pellicle; it is the model organism for bacterial cellulose but easily loses producibility via Cel− mutants.
Gluconate transporter
Gluconate transporter: bacterial membrane proteins, chiefly the GntP family (TC 2.A.8) gluconate:H+ symporters including E. coli GntT, GntU, GntP, and IdnT, with Km values of 6 to 212 μM; GntP is actually the fructuronate transporter.
Gluconeogenesis
Gluconeogenesis, also called endogenous glucose production, is de novo glucose synthesis from lactate, glycerol, pyruvate, propionate, and amino acids via pyruvate carboxylase, PEPCK, fructose-1,6-bisphosphatase, and glucose-6-phosphatase, mainly in liver and kidney cortex, distinct from glycogenolysis.
Gluconic Acid
Gluconic acid is a mild organic acid made by oxidizing glucose, produced industrially by fermentation with Aspergillus niger and used as the food additive E 574.
Gluconobacter
Gluconobacter, type species G. oxydans, a genus of Gram-negative aerobic acetic acid bacteria that incompletely oxidizes sugars via periplasmic membrane-bound dehydrogenases, used industrially for vitamin C, gluconic acid, and dihydroxyacetone production.
Gluconobacter oxydans
Gluconobacter oxydans, type species of the genus Gluconobacter, is a Gram-negative strictly aerobic acetic acid bacterium performing oxidative fermentation via membrane-bound PQQ/FAD dehydrogenases; used industrially for vitamin C (sorbitol to L-sorbose), gluconic and ketogluconic acids, and dihydroxyacetone.
Glucosamine
Glucosamine (2-amino-2-deoxy-D-glucose) is an amino sugar from chitin, a cartilage building block sold as sulfate or hydrochloride supplements for osteoarthritis, with inconsistent clinical evidence and conflicting guidelines.
Glucosamine-6-phosphate isomerase
Glucosamine-6-phosphate isomerase, also called glucosamine-6-phosphate deaminase or NagB, is a bacterial enzyme that converts D-glucosamine-6-phosphate into fructose-6-phosphate, releasing ammonia and linking amino sugar metabolism to glycolysis.
Glucose
Glucose (blood sugar, dextrose) is a six-carbon aldose monosaccharide, C6H12O6, the main energy source for cells, stored as glycogen, regulated by insulin and glucagon, and existing in water mainly as alpha and beta ring anomers.
Glucose 6-phosphate
Glucose 6-phosphate (G6P), also known as the Robison ester, is a phosphorylated glucose whose phosphate group traps it inside cells, feeding glycolysis, glycogen synthesis, and the pentose phosphate pathway.
Glucose clamp technique
The glucose clamp technique, or euglycemic clamp, is a method that holds blood glucose constant to measure insulin sensitivity, introduced by DeFronzo and colleagues in 1979.
Glucose metabolism
Glucose metabolism (glycolysis and gluconeogenesis, Reactome R-HSA-70326) covers glucose uptake to glucose 6-phosphate, glycolysis, glycogen synthesis, the pentose phosphate pathway, and liver/kidney gluconeogenesis, regulated by insulin and glucagon.
Glucose meter
A glucose meter, also known as a blood glucose meter or glucometer, is a handheld device that measures glucose in a small blood sample, usually from a fingertip.
Glucose oxidase
Glucose oxidase (GOx) is an enzyme that oxidizes glucose to gluconolactone and hydrogen peroxide. Produced mainly from Aspergillus niger, it is used in food preservation, baking, and glucose biosensors.
Glucose sensor
A glucose sensor is a device that converts glucose concentration in blood or interstitial fluid into an electrical signal, powering test strips and continuous glucose monitors.
Glucose syrup
Glucose syrup, also called corn syrup when made from cornstarch, is a purified concentrated aqueous solution of dextrose, maltose, and dextrins from partial starch hydrolysis, graded by dextrose equivalent and used to sweeten and prevent sugar crystallization.
Glucose test
Glucose test: measurement of glucose in blood or urine to screen for, diagnose, and monitor diabetes. Includes FPG, OGTT, A1C, random glucose, and gestational screening at 24–28 weeks with defined thresholds.
Glucose testing
Glucose testing is the clinical measurement of glucose concentration in blood or other body fluids, used to screen for, diagnose, and monitor diabetes and other disorders of glucose metabolism.
Glucose tolerance test
Glucose tolerance test (OGTT): diagnostic test measuring blood glucose before and after a 75-g glucose drink; 2-h values of 140–199 mg/dL indicate prediabetes, ≥200 mg/dL diabetes; also used for gestational diabetes screening.
Glucose transporter
Glucose transporters (GLUT/SLC2, SGLT/SLC5, SWEET/SLC50) are membrane proteins moving glucose into cells. Key facts: 14 GLUT isoforms, SGLT2 reabsorbs ~90% of filtered glucose, GLUT4 is insulin-responsive, SGLT2 inhibitors treat diabetes.
Glucose-1-phosphate thymidylyltransferase, short form
Glucose-1-phosphate thymidylyltransferase, short form (IPR005907, RmlA/RfbA/RffH) is a bacterial homotetrameric EC 2.7.7.24 enzyme, first of four steps in dTDP-L-rhamnose cell wall biosynthesis, feedback-inhibited by dTDP-L-rhamnose and absent from humans.