scholarly journals Phosphonomethyl analogues of phosphate ester glycolytic intermediates

1974 ◽  
Vol 141 (3) ◽  
pp. 715-719 ◽  
Author(s):  
Henry B. F. Dixon ◽  
Michael J. Sparkes
Keyword(s):  
Phosphoglycerate Kinase ◽  
Triose Phosphate Isomerase ◽  
Glycolytic Enzymes ◽  
Phosphate Group ◽  
Phosphate Ester ◽  
Dihydroxyacetone Phosphate ◽  
Triose Phosphate ◽  
Glycolytic Intermediates ◽  
Combined Action ◽  
Made In

Analogues of dihydroxyacetone phosphate and of 3-phosphoglycerate were made in which the phosphate group, –O–PO3H2, is replaced by the phosphonomethyl group, –CH2–PO3H2. The analogue of dihydroxyacetone phosphate is a substrate for aldolase and glycerol 1-phosphate dehydrogenase (Stribling, 1974), but not for triose phosphate isomerase. The analogue of 3-phosphoglycerate oxidizes NADH under the combined action of 3-phosphoglycerate kinase and glyceraldehyde 3-phosphate dehydrogenase if ATP is added. Thus four out of the five glycolytic enzymes tested handle the phosphonomethyl compounds like the natural phosphates.

scholarly journals Inhibition of glycolytic enzymes by 2-phosphotartronate

1976 ◽  
Vol 153 (3) ◽  
pp. 741-744 ◽  
Author(s):  
M K Thomas ◽  
T G Spring
Keyword(s):  
Pyruvate Kinase ◽  
Competitive Inhibition ◽  
Phosphoglycerate Kinase ◽  
Triose Phosphate Isomerase ◽  
Glycolytic Enzymes ◽  
Phosphoglycerate Mutase ◽  
Rabbit Muscle ◽  
Triose Phosphate ◽  
Permanganate Oxidation

2-Phosphotartronate has been synthesized by permanganate oxidation of glycerol 2-phosphate and has been tested as an inhibitor of five glycolytic enzymes that bind phosphoglycerate or phosphoglycollate. Competitive inhibition of rabbit muscle phosphoglycerate mutase, enolase and pyruvate kinase was observed. Triose phosphate isomerase and 3-phosphoglycerate kinase were not inhibited.

On the three-dimensional structure and catalytic mechanism of triose phosphate isomerase

1981 ◽  
Vol 293 (1063) ◽  
pp. 159-171 ◽  
Keyword(s):  
Catalytic Mechanism ◽  
Polypeptide Chain ◽  
Three Dimensional ◽  
Triose Phosphate Isomerase ◽  
Dimensional Structure ◽  
Dihydroxyacetone Phosphate ◽  
Triose Phosphate ◽  
Independent Determination ◽  
Chicken Muscle

Triose phosphate isomerase is a dimeric enzyme of molecular mass 56000 which catalyses the interconversion of dihydroxyacetone phosphate (DHAP) and D-glyceraldehyde-3-phosphate. The crystal structure of the enzyme from chicken muscle has been determined at a resolution of 2.5 A, and an independent determination of the structure of the yeast enzyme has just been completed at 3 A resolution. The conformation of the polypeptide chain is essentially identical in the two structures, and consists of an inner cylinder of eight strands of parallel |3-pleated sheet, with mostly helical segments connecting each strand. The active site is a pocket containing glutamic acid 165, which is believed to act as a base in the reaction. Crystallographic studies of the binding of DHAP to both the chicken and the yeast enzymes reveal a common mode of binding and suggest a mechanism for catalysis involving polarization of the substrate carbonyl group.

scholarly journals Enzyme-substrate and enzyme-inhibitor complexes of triose phosphate isomerase studied by 31P nuclear magnetic resonance

1979 ◽  
Vol 179 (3) ◽  
pp. 607-621 ◽  
Author(s):  
I D Campbell ◽  
R B Jones ◽  
P A Kiener ◽  
S G Waley
Keyword(s):  
Enzyme Inhibitor ◽  
Ph Dependence ◽  
Triose Phosphate Isomerase ◽  
Dihydroxyacetone Phosphate ◽  
Ligand Complex ◽  
Triose Phosphate ◽  
Kinetic Information ◽  
Transition State Analogue ◽  
Chicken Muscle ◽  
Proton Uptake

The complex formed between the enzyme triose phosphate isomerase (EC 5.3.1.1.), from rabbit and chicken muscle, and its substrate dihydroxyacetone phosphate was studied by 31P n.m.r. Two other enzyme-ligant complexes examined were those formed by glycerol 3-phosphate (a substrate analogue) and by 2-phosphoglycollate (potential transition-state analogue). Separate resonances were observed in the 31P n.m.r. spectrum for free and bound 2-phosphoglycollate, and this sets an upper limit to the rate constant for dissociation of the enzyme-inhibitor complex; the linewidth of the resonance assigned to the bound inhibitor provided further kinetic information. The position of this resonance did not vary with pH but remained close to that of the fully ionized form of the free 2-phosphoglycollate. It is the fully ionized form of this ligand that binds to the enzyme. The proton uptake that accompanies binding shows protonation of a group on the enzyme. On the basis of chemical and crystallographic information [Hartman (1971) Biochemistry 10, 146–154; Miller & Waley (1971) Biochem. J. 123, 163–170; De la Mare, Coulson, Knowles, Priddle & Offord 1972) Biochem. J. 129, 321–331; Phillips, Rivers, Sternberg, Thornton & Wilson (1977) Biochem. Soc. Trans. 5, 642–647] this group is believed to be glutamate-165. On the other hand, the position of the resonance of D-glycerol 3 phosphate (sn-glycerol 1-phosphate) in the enzyme-ligand complex changes with pH, and both monoanion and dianon of the ligand bind, although dianion binds better. The substrate, dihydroxyacetone phosphate, behaves essentially like glycerol 3-phosphate. The experiments with dihydroxy-acetone phosphate and triose phosphate isomerase have to be carried out at 1 degree C because at 37 degrees C there is conversion into methyl glyoxal and orthophosphate. The mechanismof the enzymic reaction and the reasons for rate-enhancement are considered, and aspects of the pH-dependence are discussed in an Appendix.

scholarly journals Mode of action of α-chlorohydrin as a male anti-fertility agent. Inhibition of the metabolism of ram spermatozoa by α-chlorohydrin and location of block in glycolysis

1978 ◽  
Vol 170 (1) ◽  
pp. 23-37 ◽  
Author(s):  
Patricia D. C. Brown-Woodman ◽  
Hideo Mohri ◽  
Toshiko Mohri ◽  
Dai Suter ◽  
Ian G. White
Keyword(s):  
Dehydrogenase Activity ◽  
Recovery Period ◽  
Triose Phosphate Isomerase ◽  
Glycolytic Enzymes ◽  
Unexpected Finding ◽  
Glycolytic Intermediate ◽  
Enzyme Preparations ◽  
Triose Phosphate

1. The effect of α-chlorohydrin on the metabolism of glycolytic and tricarboxylate-cycle substrates by ram spermatozoa was investigated. The utilization and oxidation of fructose and triose phosphate were much more sensitive to inhibition by α-chlorohydrin (0.1–1.0mm) than lactate or pyruvate. Inhibition of glycolysis by α-chlorohydrin is concluded to be between triose phosphate and pyruvate formation. Oxidation of glycerol was not as severely inhibited as that of the triose phosphate. This unexpected finding can be explained in terms of competition between glycerol and α-chlorohydrin. A second, much less sensitive site, of α-chlorohydrin inhibition appears to be associated with production of acetyl-CoA from exogenous and endogenous fatty acids. 2. Measurement of the glycolytic intermediates after incubation of spermatozoal suspensions with 15mm-fructose in the presence of 3mm-α-chlorohydrin showed a ‘block’ in the conversion of glyceraldehyde 3-phosphate into 3-phosphoglycerate. α-Chlorohydrin also caused conversion of most of the ATP in spermatozoa into AMP. After incubation with 3mm-α-chlorohydrin, glyceraldehyde 3-phosphate dehydrogenase and triose phosphate isomerase activities were decreased by approx. 90% and 80% respectively, and in some experiments aldolase was also inhibited. Other glycolytic enzymes were not affected by a low concentration (0.3mm) of α-chlorohydrin. Loss of motility of spermatozoa paralleled the decrease in glyceraldehyde 3-phosphate dehydrogenase activity. α-Chlorohydrin, however, did not inhibit glyceraldehyde 3-phosphate dehydrogenase or triose phosphate isomerase in sonicated enzyme preparations when added to the assay cuvette. 3. Measurement of intermediates and glycolytic enzymes in ejaculated spermatozoa before, during and after injection of rams with α-chlorohydrin (25mg/kg body wt.) confirmed a severe block in glycolysis in vivo at the site of triose phosphate conversion into 3-phosphoglycerate within 24h of the first injection. Glyceraldehyde 3-phosphate dehydrogenase activity was no longer detectable and both aldolase and triose phosphate isomerase were severely inhibited. Spermatozoal ATP decreased by 92% at this time, being quantitatively converted into AMP. At 1 month after injection of α-chlorohydrin glycolytic intermediate concentrations returned to normal in the spermatozoa but ATP was still only 38% of the pre-injection concentration. Motility of spermatozoa was, however, as good as during the pre-injection period. The activity of the inhibited enzymes also returned to normal during the recovery period and 26 days after injection were close to pre-injection values. 4. An unknown metabolic product of α-chlorohydrin is suggested to inhibit glyceraldehyde 3-phosphate dehydrogenase and triose phosphate isomerase of spermatozoa. This results in a lower ATP content, motility and fertility of the spermatozoa. Glycidol was shown not to be an active intermediate of α-chlorohydrin in vitro.

scholarly journals Specificity and kinetics of triose phosphate isomerase from chicken muscle

1972 ◽  
Vol 129 (2) ◽  
pp. 301-310 ◽  
Author(s):  
Sylvia J. Putman ◽  
A. F. W. Coulson ◽  
I. R. T. Farley ◽  
B. Riddleston ◽  
J. R. Knowles
Keyword(s):  
Triose Phosphate Isomerase ◽  
Proton Exchange ◽  
The Other ◽  
Chicken Breast ◽  
Dihydroxyacetone Phosphate ◽  
Exchange Reactions ◽  
Hydrogen Atoms ◽  
Triose Phosphate ◽  
Chicken Muscle ◽  
Kinetics Of

The isolation of crystalline triose phosphate isomerase from chicken breast muscle is described. The values of kcat. and Km for the reaction in each direction were determined from experiments over wide substrate-concentration ranges, and the reactions were shown to obey simple Michaelis–Menten kinetics. With d-glyceraldehyde 3-phosphate as substrate, kcat. is 2.56×105min-1and Km is 0.47mm; with dihydroxyacetone phosphate as substrate, kcat. is 2.59×104min-1and Km is 0.97mm. The enzyme-catalysed exchange of the methyl hydrogen atoms of the ‘virtual substrate’ monohydroxyacetone phosphate with solvent2H2O or3H2O was shown. This exchange is about 104-fold slower than the corresponding exchange of the C-3 hydrogen of dihydroxyacetone phosphate. The other deoxy substrate, 3-hydroxypropionaldehyde phosphate, was synthesized, but is too unstable in aqueous solution for analogous proton-exchange reactions to be studied.

scholarly journals The existence of an electrophilic component in the reaction catalysed by triose phosphate isomerase

1974 ◽  
Vol 141 (2) ◽  
pp. 589-592 ◽  
Author(s):  
Martin R. Webb ◽  
Jeremy R. Knowles
Keyword(s):  
Carbonyl Group ◽  
Triose Phosphate Isomerase ◽  
Dihydroxyacetone Phosphate ◽  
Free Solution ◽  
Triose Phosphate ◽  
Order Of Magnitude

In the presence of triose phosphate isomerase, the substrate dihydroxyacetone phosphate is reduced stereoselectively by NaBH4. The reduction of enzyme-bound substrate is almost completely or completely stereoselective and occurs about one order of magnitude faster than that in free solution. This acceleration implies a polarization of the carbonyl group when dihydroxyacetone phosphate is bound.

scholarly journals Loss of Peroxisomal Hydroxypyruvate Reductase Inhibits Triose Phosphate Isomerase but Stimulates Cyclic Photosynthetic Electron Flow and the Glc-6P-Phosphate Shunt

2018 ◽  
Author(s):  
Jiying Li ◽  
Sarathi M. Weraduwage ◽  
Alyssa L. Preiser ◽  
Sean E. Weise ◽  
Deserah D. Strand ◽  
...  
Keyword(s):  
Photosystem I ◽  
Electron Flow ◽  
Competitive Inhibitor ◽  
Triose Phosphate Isomerase ◽  
Cyclic Electron Flow ◽  
Dihydroxyacetone Phosphate ◽  
Triose Phosphate ◽  
Hydroxypyruvate Reductase ◽  
Photosynthetic Electron Flow ◽  
Mutant Lines

AbstractThe oxygenation of ribulose 1,5-bisphosphate by Rubisco is the first step in photorespiration and reduces the efficiency of photosynthesis in C3 plants. Our recent data indicates that mutants in photorespiration have increased rates of photosynthetic cyclic electron flow around photosystem I. We investigated mutant lines lacking peroxisomal hydroxypyruvate reductase to determine if there are connections between 2-PG accumulation and cyclic electron flow. We found that 2-PG is a competitive inhibitor of triose phosphate isomerase (TPI), an enzyme in the Calvin-Benson cycle that converts glyceraldehyde 3-phosphate to dihydroxyacetone phosphate. This block in metabolism could be overcome if glyceraldehyde 3-phosphate is exported to the cytosol where the cytosolic triose phosphate isomerase could convert it to dihydroxyacetone phosphate. We found evidence that carbon is reimported as Glc-6P-phosphate forming a cytosolic bypass around the block of stromal TPI. However, this also stimulates a Glc-6P-phosphate shunt, which consumes ATP, which can be compensated by higher rates of cyclic electron flow.Once Sentence SummaryTriose phosphate isomerase is inhibited in plants lacking hydroxypyruvate reductase 1 and this is overcome by exporting triose phosphate to the cytosol and importing Glc-6P, which stimulates a Glc-6P-phosphate shunt and cyclic electron flow.

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