| Term | Definition |
|---|
| Hexokinase | Enzyme responsible for the first irreversible step of glycolysis. |
| Phosphofructo Kinase | Enzyme responsible for the second irreversible step of glycolysis. |
| Pyruvate Kinase | Enzyme responsible for the third irreversible step of glycolysis. |
| Glucose 6 Phosphatase | By-Pass enzyme that catalyzes the reverse reaction of hexokinase in gluconeogenesis. |
| Fructose 1,6-Bisphosphatase | Enzyme that catalyzes the reverse reaction of phosphofructo kinase in gluconeogenesis. |
| Pyruvate Carboxylase | One of the two enzymes required to catalyze the reverse reaction of pyruvate kinase. Requires biotin as a cofactor. Responsible for making oxaloacetate from pyruvate. Up-regulated by acetyl CoA. |
| Phosphoenolpyruvate Carboxykinase | One of the two enzymes required to catalyze the reverse reaction of pyruvate kinase. Requires GTP. Makes oxaloactetate into phosphoenolpyruvate. |
| Malate Dehydrogenase | Responsible for the interconversion of malate and oxaloacetate. Important for the movement of substrates out of the mitochondira in gluconeogenesis. |
| Biotin holcarboxylase synthetase | covalently links the free carboxyl group of biotin to a specific lysine residue of the enzyme. |
| Biotinidase | Catalyzes the removal of biotin from enzymes during protein turnover. |
| Avidin | Prevents biotin absorption because of its high biotin affinity. |
| Hexosaminidase A | If defective, enzyme responsible for Tay-Sachs disease because gangliosides ending with GalNAc cannot be degraded. |
| Beta-Glucosidase | If defective, enzyme responsible for Gaucher's Disease because of an accumulation of glucocerebroside. |
| Sphingomyelinase | If defective, enzyme responsible for Niemann-Pick Disease because it is unable to degrade the Cer-Phospho-Choline bond of sphingomyelin. |
| Phospholipase A1 | Acts on phospholipids, removes a fatty acid unit from position 1, creating lysophosphoglyceride lacking acyl-1. |
| Phospholipase A2 | Acts on phospholipids, removes a fatty acid unit from position 2, creating lysophosphoglyceride lacking acyl-2. |
| Phospholipase C | Acts on phospholipids, removes the phospho alcohol group, leaving diaclglcerol. |
| Phospholipase D | Acts on phospholipids, removes the alchol group, leaving phosphatidic acid. |
| Cyclooxygenase | One of two enzymes of prostaglandin synthase, forms the cyclopentane ring. Important in the synthesis of prostaglandin H2 from arachidonate. |
| Hydroperoxidase | The second enzyme of prostaglandin synthase, converts the O-OH to OH. |
| Prostaglandin Synthase | Two enzyme complex that makes prostaglandin H2 from arachidonate. Cyclooxygenase is inhibited by aspirin and iburpofen in this complex. |
| Thromboxane synthase | Enzyme responsible for making thromboxanes from prostaglandin H2. |
| Lipoxygenase | Enzyme responsible for making leukotrienes from arachiodonate. The site where accolate acts. |
| Prostacyclin Synthase | Enzyme responsible for mkaing prostacyclins from prostaglandin H2. |
| HMG-CoA Reductase | Main regulatory step for cholesterol synthesis. Makes mevalonate. Requries two NADPH molecules. |
| cis-prenyltransferase | Enzyme responsible for the formation of geranyl-PP from two isporene units. |
| Squalene Synthase | Enzyme responsible for the reductive condensation of two farnesyl-PP to squalene. |
| Squalene epoxidase | Enzyme that activates squalene to create squalene epoxide, first step in the final state of cholesterol synthesis. |
| Oxidosqualene:lanosterol cyclase | Enzyme that closes the ring structure to make the first sterol intermediate in cholesterol synthesis, lanosterol. |
| Desmolase | Enzyme that removes 6 carbon unit from cholesterol in the synthesis of pregenolone. |
| Aromatase | Enzyme required to convert androgens to estrogens. |
| Hydroxylase enzymes | Add hydroxyl groups, important in the formation of steroid hormones because these hydroxylations provide the difference between different hormones. |
| Cytochrome P450 monooxygenases | Mixed function oxidase, responsible for the hydroxylation of steroids. |
| Gastric Lipase | Secreted by glands in the stomach, acts on triglycerides to produce fatty acid and diglycerides. |
| Cholecystokinin | Stimulates contraction of the gall bladder, forcing bile into the duodenum. |
| Pancreatic Lipase | Binds to the surface of a lipid emulsion to break down lipids. |
| Cholesterol Esterase | Hydrolyzes cholesterol esters into cholesterol and a free fatty acid. |
| Lipoprotein Lipase | Enzyme activated by Apo C-II, binds to chylomicrons and hydrolyzes fatty acids from tryglicerides. |
| Phosphorylase | Breaks alpha 1-4 glucosidic bonds of glycogen, creating glucose 1 phosphate. |
| Amylo 1-6 Glucosidase | One of two enzymes in debranching enzyme complex. Hydrolyzes the alpha 1-6 glucosidic bond in glycogen. |
| Glycosyl 4:4 transferase | One of the enzymes in the debranching enzyme complex, removes 3 of the 4 glucose residues from a 4 residue branch of glycogen, and moves it to the end of a glycogen stub. |
| Phosphoglucomutase | Interconverts glucose 1 phosphate and glucose 6 phosphate. Requires glucose 1,6 bisphosphate as a cofactor. |
| Glycogenin | Required for de novo synthesis of glycogen. Part of the glycogen primer with 10 glucose residues. |
| UDPG Pyrophosphorylase | Enzyme that makes Uridine di phosphoglucose from glucose 1 phosphate, which is required for the synthesis of glycogen primer. |
| Glycogen Synthase | Enzyme responsible for adding UDPglucose to growing glycogen chain. |
| Branching Enzyme | Enzyme that transfers 7 glucoses and forms alpha 1-6 branch in glycogen. |
| Protein Kinase A | Enzyme activated by cyclic AMP that phosphorylates phosphorylase kinase, making it active. Also phosphorylates glycogen synthase, inactivating it. |
| Phosphorylase Kinase | Enzyme that when phosphorylated, phosphorylates phosphorylase, activating it. |
| Transaminase | Enzyme that transfers amino groups. For example-alpha ketogluterate to glutamate requires this enzyme. |
| Glutamate Dehydrogenase | This enzyme requires NADP, releases ammonia for urea synthesis. |
| Glutamine Synthetase | Enzyme that makes glutamine from glutamate. |
| Glutaminase | Enzyme that releases NH4+ from glutamine, making glutamate. |
| Aspartate Aminotransferase | Enzyme that catalyzes the exchange of an amino group from aspartate to alpha ketoglutarate. Making oxaloacetate and glutamate. |
| Alanine Aminotransferase | Enzyme that catalyzes the exchange of an amino group from alanine to alpha ketogluterate, resulting in pyruvate and glutamate. |
| Carbamoyl-Phosphate Synthetase | This enzyme is activated by N-acetylglutamate, uses NH3, 2 ATP and bicarbonate. |
| Ornithine Transcarbamylase | This enzyme condenses carbomyl phosphate and ornithine to make citrulline. |
| Argininosuccinate Synthetase | This enzyme uses aspartic acid and ATP to make citrulline into argininosuccinate. |
| Argininosuccinate Lyase | This enzyme makes fumarate and arginine from argininosuccinate. |
| Arginase | This enzyme releases urea from arginine. Present in liver but absent in kidney. The result of this action also creates ornithine. |
| Calcineurin | Ca2+ dependent phosphatase which activates Na+/K+ ATPase. |
| Serine Hydroxymethyl-Transferase | Enzyme that catalyzes the formation of serine from glycine. |
| Serine Dehydratase | Enzme that makes pyruvate through an aminoacrylate intermediate from serine. |
| Threonine Aldolase | Enzyme that makes acetaldehyde and glycine from threonine. |
| Branched Chain AA Transaminase | Enzyme that makes alpha keto acids from branched chain amino acids. |
| Branched Chain Keto Acid Dehydrogenase Complex | Enzyme responsible for the oxidative decarboxylation of keto acids from branched chain amino acids. |
| Phenylalanine Hydroxylase | Enzyme responsible for converting phenylalanine into tyrosine. |
| Homogentisate Oxidase | Enzyme if defective leads to alkaptonuria due to the buildup of homogentisic acid. |
| Methionine Adenosyl-Transferase | Enzyme that catalyzes the exchange of adensyl group to methionine, requires ATP. |
| Methionine Synthase | Enzyme that makes methionine from homocysteine, requires B12. |
| Methylmalonyl-CoA Mutase | Enzyme that converts methylmalonyl CoA to Succinyl CoA, requires B12. |
| Cystathionine Beta-Synthase | Enzyme that combines homocysteine and serine into cystathionine. |
| Cystathionine Lyase | Enzyme that releases NH4+ when it breaks cystathionine into cysteine and alpha-ketobutyrate. |
| Asparagine synthetase | Enzyme that makes asparagine and glutamate from aspartate and glutamine. |
| Nitric Oxide Synthase | Enzyme that uses arginine and O2 to make NO and citrulline. This enzyme requires NADPH. |
| Hormone Sensitive Lipase | This enzyme catalyzes hydrolysis of ester bonds, FA<-->Glycerol, and mobilizes FA from adipose |
| Lecithin:Cholesterol Acyl Transferase | This enzyme is responsible for the formation of cholesterol esters and lysophosphatidylcholine. |
| Glutamyl Cysteine Synthetase | Enzyme involved in the first step of glutathione synthesis. Makes glutamyl cysteine from glutamate and cysteine. |
| Glutathione Synthetase | Enzyme in the second step of glutathione synthesis. Glycine is added to glutamyl cysteine. |
| Glutathione Reductase | Enzyme uses NADPH to reduce glutathione. |
| Glutathione Peroxidase | Enzyme that oxidizes glutathione, uses hydrogen peroxide. |
| Methemoglobin Reductase I | Also known as cytochrome b5 reductase, also diapherase. Responsible for reducing methemoglobin using NADH. |
| Spectrin | Protein found in RBCs that cause their characteristic biconclave shape; connects proteins in the plasma membrane with actin in the cytoskeleton |
| Ankyrin | Protein linking Na, K, ATPase with the cytoskeleton. |
| Band 3 | Transports HCO3- and Cl- across the plasmamembrane. Protein is glycosylated. |
| Carbonic Anhydrase | This protein catalyzes the hydration of CO2. |
| Glycophorin | Membrane spanning glyco-protein, basis of the MNS blood group. |
| Ferric Reductase | Enzyme that reduces ferric iron to ferrous form. |
| Divalent Metal Transporter 1 | Proton coupled transporter of ferrous iron. |
| Ferritin | Sequesters iron as ferrihydrate. |
| Ferroportin | Also known as basolateral transporter, moves ferrous iron from the basolateral surface. It is a ferroxidase. |
| Hephaestin | Copper ferroxidase, acts with ferroportin in iron transport. |
| Stimulator of Iron Transport | Transports both ferric and ferrous iron. |
| Heme Oxidase | Catalyzes the removal of iron from heme. |
| Ceruloplasmin | Soluble copper ferroxidase that is involved in delivery of iron to tissues. |
| Hepcidin | Negative regulator of iron release. |
| Transferrin | Iron binding glycoprotein that carries iron in plasma. |
| Aminolevulinate Synthase | Enzyme catalyzing the committed step of heme synthesis. Makes aminolevulinate from succinyl CoA and glycine. B6 dependent enzyme. |
| Aminolevulinate Dehydratase | This enzyme forms porphobilinogen from two aminolevulinates. |
| Porphorobilinogen Deaminase | Enzyme requiring dipyrromethane prosthetic group. Builds hydroxymethybilane by adding succesive porphorobilinogens. |
| Uroporphyrinogen III Cosynthase | This enzyme converts hydroxymethylbilane to uroporphyrinogen III. |
| Ferrochelatase | This enzyme inserts iron into protoporphyrin IX, making heme. |
| Haptaglobin | This enzyme binds hemoglobin dimers, preventing their loss through the urine. |
| Albumin | Serum protein, many protein binding sites, including hemin (oxidized heme) forming methemalbumin. |
| Hemopexin | Binds hemin, allowing the complex to be taken up by the liver. |
| Heme Oxygenase | Oxygen and NADPH are required by this enzyme to make heme into biliverdin. |
| Biliverdin Reductase | This enzyme uses NADPH to make bilirubin from biliverdin. |
| UDP-Glucuronosyl Transferase | This enzyme conjugates glucuronides onto bilirubin, making it more soluble, allowing it to be excreted. |
| Beta-Glucuronidases | These enzmyes cleave bilirubin glucuronides, comes mostly from bacterial flora. |
Combine with other sets
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