Triosephosphate dehydrogenase isomerase

The second type of a-glycerolphosphate dehydrogenase was first described by Green" as a particulate system which was coupled to cytochrome c. This particulate system has now been solubilized by treatment with sodium desoxycholate. On further purification the enzyme was separated from triosephosphate dehydrogenase, isomerase, and catalase activities and no longer was capable of reducing cytochrome c. It also did not react with DPN, TPN, or FAD, although it readily reduced suitable dyes. The reaction product was dihydroxyacetone phosphate. 

The differential expression of paired cancerous and non-cancerous tissues was visually compared, and 11 spots were up-regulated in cancerous tissues alpha-enolase, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) 2 (spots), triosephosphate isomerase, transgelin, calmodulin, MnSOD, PDI A3, cyclophilinA, GST-P, and apolipoprotein A-I precursor (23). 

Z F6P + ATP + 2 NADH + H+ <-> 2 glycerol-3-phosphate + ADP + 2 NAD+ where F6P is fructose-6-phosphate, FDP is fructose-1,6-diphosphate, DHA-P is dihydroxyacetone phosphate, TIM is triosephosphate isomerase, and GDH is glycerol-3-phosphate dehydrogenase. The oxidation of NADH is a measure of the 6-PFK activity and is determined photometrically (decrease of OD per minute) [4]. 

Another assay for phosphoffuctokinase involves converting the fructose 1,6-diphosphate to dihydroxyacetone phosphate and glyceraldehyde 3-phosphate with aldolase, equilibrating the triosephosphates with triosephosphate isomerase, and then measuring the production of NADH on the oxidation of the glyceraldehyde phosphate by glyceraldehyde 3-phosphate dehydrogenase. 

RNS, ribonuclease LZM, lysozyme SNS, staphylococcal nuclease LZ4, T4 lysozyme PAP, papain TLS, thermolysin, TRX, thioiedoxin FLN, flavodoxin ADH, alcohol dehydrogenase coenzyme domain AKN, adenyl kinase MDG, malate dehydrogenase TIM, triosephosphate isomerase SUB, subtilisin CPA, carboxypeptidase LDH, lactate dehydrogenase PGK, phosphoglycerate kinase GPD, glyceraldehyde 3-phosphate dehydrogenase, HKN, hexokinase. 

A V- - NAD+ Triosephosphate Isomerase y"— NADH Glyceraldehyde Phosphate Dehydrogenase 1,3-Bisphosphoglycerate A U -ADP... 

T. aquaticus, and comparison of this sequence with that of the lobster muscle enzyme shows a sequence identity of 50% which is again significantly higher than was found in comparison of bacterial and liver alcohol dehydrogenase (33) or bacterial and muscle triosephosphate isomerase (SP). 

Eukaryotic peptide chain elongation factor-2 Triosephosphate isomerase Myo-inositol-phosphate synthase Mannose-1-phosphate guanylj transferase Alcohol dehydrogenase Aldehyde reductase Ade5... 

Vajda S, Camacho CJ. Protein-protein docking is the glass half-full or half-empty Trends Biotechnol. 2004 22 110-116. Derreumaux P, Schlick T. The loop opening/closing motion of the enzyme triosephosphate isomerase. Biophys. J. 1998 74 72-81. Gerstein M, Chothia C. Analysis of protein loop closure. Two types of hinges produce one motion in lactate dehydrogenase. J. Mol Biol 1991 220 133-149. 

Spectrophotometric assay (BIO, L7, S29) is accomplished by a similar incubation, without hydrazine, where excess added triosephosphate isomerase converts triose phosphate formed to DAP, in turn removed as glycerophosphate by reduced nicotinamide-adenine dinucleotide (NADH2, formerly termed DPNH) and added glycerophosphate dehydrogenase. 

All assay methods are based on the forward ALD-catalyzed reaction. Both photometric fixed-time and continuous-monitoring procedures have been developed. In the analytical approach on which all the commonly used procedures and kits are based, the ALD reaction is coupled with two other enzyme reactions. Triosephosphate isomerase (EC 5.3.1.1) is added to ensure rapid conversion of all GLAP to DAP. Glycerol-3-phosphate dehydrogenase (EC 1.1.1.8) is added to reduce the DAP to glycerol-3-phosphate, with NADH acting as hydrogen donor. The decrease in NADH concentration is then measured. 

Triosephosphate Isomerase Glyceradehyde-3-Phosphate Dehydrogenase Phosphoglycerate Kinase Phosphoglycerate Mutase Enolase... 

A number of studies on the metabolism of 3FG and 4FG in Locusta miaratoria have been undertaken. Both 3FG and 4FG are toxic to locust with LD50 s of 4.8 mg/g and 0.6 mg/g respectively. In vitro studies showed that 3FG is metabolized in the fat body, via the NADP-linked aldose reductase, to 3-deoxy-3-fluoro-D-glucitol (3FGL). This metabolite was detected in the hemolymph of the insect and shown to be both a competitive inhibitor and a substrate for NAD-linked sorbitol dehydrogenase, thereby generating 3-deoxy-3-fluoro-D-fructose (3FF) (541. Subsequently, it was shown by in vivo radio-respirometric analysis of C02 and appropriate chase experiments, that 3FG metabolism irreversibly inhibits glycolysis and not the hexose monophosphate shunt or tricarboxylic acid cycle (55). In addition, the release of fluoride ion and H20 from D-[3- H]-3FG was also observed. Based on the mechanism of aldolase (55) and triosephosphate isomerase... 

Triosephosphate Isomerase, Glyceraldehyde-3-Phosphate Dehydrogenase, and Phosphoglycerate Kinase. These enzymes catalyze the next three steps of glycolysis and are nearly-uniformly represented in all organisms. The... 

Mixed packings of a helices and P strands. Protein stractures (e.g. alcohol dehydrogenase, triosephosphate isomerase) composed of a heUces and p strands that roughly alternate along the peptide chain (ot/p), can be folded into two classes ... 

Data taken form Craik et al. (1987) for rat trypsin Wilks et al. (1990) for B. stereothermophilus lactate dehydrogenases Muraki et al. (1992) for human lysozyme in which the active site residues refer to E35, D53, W64, D102 and W109 and AGr = -RTIn[(koat/Kra)niutant/ (kcat/Kra)wiidl Stebbins and Kantrowitz (1992) for B. subtilis aspartate transcarbamylase Casal et al. (1987) for yeast triosephosphate isomerase Dupureur et al. (1992) for pancreatic phospholipase Mrabet et al. (1992) for Actinoplanes missouriensis xylose isomerase. 

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