Inhibition of glyceraldehyde 3-phosphate dehydrogenase in boar spermatozoa by bromohydroxypropanone

1995 ◽  
Vol 7 (1) ◽  
pp. 107 ◽  
Author(s):  
LM Porter ◽  
AR Jones
Keyword(s):  
Carbonyl Compound ◽  
Energy Charge ◽  
Mature Sperm ◽  
Dihydroxyacetone Phosphate ◽  
Epididymal Sperm ◽  
Charge Potential ◽  
Fructose 1,6 Bisphosphate ◽  
Boar Spermatozoa

In the presence of 3-bromo-1-hydroxypropanone (BOP), cauda epididymal sperm obtained from mature boars produced a carbonyl compound which is assumed to be (S)-3-bromolactaldehyde. Glyceraldehyde 3-phosphate dehydrogenase was rapidly inhibited which resulted in the accumulation of dihydroxyacetone phosphate and fructose-1,6-bisphosphate, and no accumulation of lactate when fructose was the substrate. The energy charge potential of the cells declined in the presence of BOP when either fructose or glycerol were substrates. It is suggested that BOP is transformed into (S)-3-bromolactaldehyde, which is the actual inhibitor of glyceraldehyde 3-phosphate dehydrogenase, thus demonstrating BOP to be the first brominated chemical to have an anti-glycolytic action on mature sperm in vitro.

scholarly journals Inhibition of Fructolysis in Boar Spermatozoa by the Male Antifertility Agent (S)-a-Chlorohydrin

1982 ◽  
Vol 35 (6) ◽  
pp. 595 ◽  
Author(s):  
Denise Stevenson ◽  
A RJones
Keyword(s):  
Oxidative Metabolism ◽  
Inhibitory Activity ◽  
Energy Charge ◽  
Substrate Level Phosphorylation ◽  
Charge Potential ◽  
Substrate Level ◽  
Glyceraldehydephosphate Dehydrogenase ◽  
Fructose 1,6 Bisphosphate ◽  
Boar Spermatozoa

The (S)-isomer of the male antifertility agent IX-chlorohydrin strongly inhibited the oxidative metabolism of fructose by boar spermatozoa in vitro. The result of this action, which has been deduced to be an inhibition of glyceraldehydephosphate dehydrogenase, caused an accumulation of fructose- 1,6-bisphosphate and the triosephosphates, and a decrease in substrate-level phosphorylation with a concomitant lowering of the energy charge potential of the spermatozoa. The (R)-isomer of IX-chlorohydrin had no inhibitory activity on fructolysis.

Triosephosphate metabolism by mature boar spermatozoa

1997 ◽  
Vol 9 (6) ◽  
pp. 577 ◽  
Author(s):  
A. R. Jones
Keyword(s):  
Glycolytic Pathway ◽  
Dihydroxyacetone Phosphate ◽  
Glycolytic Intermediates ◽  
Boar Sperm ◽  
Equilibrium Concentrations ◽  
Fructose 1,6 Bisphosphate ◽  
Boar Spermatozoa

Boar sperm rapidly interconverted dihydroxyacetone phosphate and glyceraldehyde 3-phosphate, produced fructose-1,6-bisphosphate, approximately equilibrium concentrations of fructose 6-phosphate and glucose 6-phosphate but not glycerol or glycerol 3-phosphate. In the presence of 3-chloro-1-hydroxypropanone, an inhibitor of stage 2 of the glycolytic pathway, the triosephosphates were metabolized faster, produced less fructose-1,6-bisphosphate, fructose 6-phosphate and glucose 6-phosphate, but not glycerol or glycerol 3-phosphate. This suggests that these cells may have the capacity to convert glycolytic intermediates into a storage metabolite to conserve carbon atoms for the eventual synthesis of lactate.

scholarly journals Erythrocyte glycolysis and its marked alterations by muscular exercise in type VII glycogenosis

Blood ◽  
1988 ◽  
Vol 71 (4) ◽  
pp. 1130-1134 ◽  
Author(s):  
T Shimizu ◽  
N Kono ◽  
H Kiyokawa ◽  
Y Yamada ◽  
N Hara ◽  
...  
Keyword(s):  
Bed Rest ◽  
Normal Subjects ◽  
Dihydroxyacetone Phosphate ◽  
Crossover Point ◽  
Control Value ◽  
Myogenic Factors ◽  
Fructose 1,6 Bisphosphate ◽  
2,3 Dpg ◽  
Ergometric Exercise

Abstract Levels of erythrocyte glycolytic intermediates after the phosphofructokinase (PFK) step, including 2,3-bisphosphoglycerate (2,3- DPG), were decreased at rest in patients from separate families with type VII glycogenosis. The concentration of 2,3-DPG was about half of the normal control value during a period of unrestricted daily activity but was further decreased to one third of normal after a one-day bed rest. Mild ergometric exercise rapidly increased the levels of fructose- 1,6-bisphosphate, dihydroxyacetone phosphate plus glyceraldehyde-3- phosphate, and 2,3-DPG in patients' circulating erythrocytes but did not in those of normal subjects. This indicated that a crossover point at the PFK step in glycolysis disappeared after physical exercise and, consequently, the 2,3-DPG concentration, which had decreased because of blockage of the PFK step, was restored considerably. This apparently exercise-related alteration in intermediary metabolism at the beginning of glycolysis was reproduced in vitro by incubating normal erythrocytes in the presence of inosine or ammonia, both of which have increased levels in circulating blood during and after exercise in this disorder. We conclude that physical activity in addition to a genetic deficiency in erythrocyte PFK affects glycolysis in erythrocytes in type VII glycogenosis and that myogenic factors released from exercising muscles may be responsible for this change.

scholarly journals Effector-Mediated Interaction of CbbRI and CbbRII Regulators with Target Sequences in Rhodobacter capsulatus

2004 ◽  
Vol 186 (23) ◽  
pp. 8026-8035 ◽  
Author(s):  
Padungsri Dubbs ◽  
James M. Dubbs ◽  
F. Robert Tabita
Keyword(s):  
Rhodobacter Capsulatus ◽  
Energy Charge ◽  
Dnase I ◽  
Pentose Phosphate ◽  
In Vivo Studies ◽  
Mobility Shift ◽  
Fructose 1,6 Bisphosphate ◽  
Target Promoters

ABSTRACT In Rhodobacter capsulatus, genes encoding enzymes of the Calvin-Benson-Bassham reductive pentose phosphate pathway are located in the cbbI and cbbII operons. Each operon contains a divergently transcribed LysR-type transcriptional activator (CbbRI and CbbRII) that regulates the expression of its cognate cbb promoter in response to an as yet unidentified effector molecule(s). Both CbbRI and CbbRII were purified, and the ability of a variety of potential effector molecules to induce changes in their DNA binding properties at their target promoters was assessed. The responses of CbbRI and CbbRII to potential effectors were not identical. In gel mobility shift assays, the affinity of both CbbRI and CbbRII for their target promoters was enhanced in the presence of ribulose-1,5-bisphosphate (RuBP), phosphoenolpyruvate, 3-phosphoglycerate, 2-phosphoglycolate. ATP, 2-phosphoglycerate, and KH2PO4 were found to enhance only CbbRI binding, while fructose-1,6-bisphosphate enhanced the binding of only CbbRII. The DNase I footprint of CbbRI was reduced in the presence of RuBP, while reductions in the CbbRII DNase I footprint were induced by fructose-1,6-bisphosphate, 3-phosphoglycerate, and KH2PO4. The current in vitro results plus recent in vivo studies suggest that CbbR-mediated regulation of cbb transcription is controlled by multiple metabolic signals in R. capsulatus. This control reflects not only intracellular levels of Calvin-Benson-Bassham cycle metabolic intermediates but also the fixed (organic) carbon status and energy charge of the cell.

Metabolism of lactate by mature boar spermatozoa

1997 ◽  
Vol 9 (2) ◽  
pp. 227 ◽  
Author(s):  
A. R. Jones
Keyword(s):  
Lactate Dehydrogenase ◽  
Nicotinamide Adenine Dinucleotide ◽  
Energy Charge ◽  
High Energy ◽  
The Other ◽  
Glycolytic Metabolism ◽  
Lactate Transport ◽  
Lactate Dehydrogenase Isozymes ◽  
Charge Potential ◽  
Boar Spermatozoa

Boar sperm oxidatively metabolized fructose, glucose, glycerol, glycerol 3-phosphate and lactate to CO2 but pyruvate produced only small amounts of CO2 and this was almost completely prevented when endogenous glycolytic metabolism was inhibited. Lactate was the preferred substrate over fructose, glycerol and glycerol 3-phosphate and when lactate was offered in the presence of pyruvate, lactate was preferentially oxidized to CO2. The rate of oxidation of fructose, glycerol and glycerol 3-phosphate was approximately halved in the presence of equi-molar concentrations of lactate and the metabolism of lactate was progressively decreased in the presence of increasing concentrations of mersalyl, an inhibitor of lactate transport. Sperm maintained a high energy charge potential when incubated with lactate as substrate in the presence or absence of bromopyruvate, an inhibitor of endogenous glycolytic metabolism. This evidence confirms that it is lactate, rather than pyruvate, that enters the mitochondria thereby constituting a lactate–pyruvate transport system in these cells for regenerating cytoplasmic nicotinamide adenine dinucleotide (NAD +). Electrophoretic examination of the lactate dehydrogenase isozymes from sperm and several other tissues of the boar showed that sperm contained almost entirely an isozyme which was not present in the other tissues.

Metabolism of fructose-1,6-bisphosphate by mature boar spermatozoa

1991 ◽  
Vol 3 (5) ◽  
pp. 609 ◽  
Author(s):  
AR Jones ◽  
MD Montague
Keyword(s):  
Carbon Dioxide ◽  
Dihydroxyacetone Phosphate ◽  
High Concentration ◽  
Atp Levels ◽  
High Concentrations ◽  
Fructose 1,6 Bisphosphate ◽  
Boar Spermatozoa

Mature epididymal boar spermatozoa converted glucose and fructose to carbon dioxide and lactate and maintained high concentrations of ATP. In the presence of (S)-alpha-chlorohydrin these processes were inhibited and there was an accumulation of fructose-1,6-bisphosphate and dihydroxyacetone phosphate. With fructose-1,6-bisphosphate as the substrate, the concentration of ATP was maintained, carbon dioxide was evolved and dihydroxyacetone phosphate accumulated. Cells pre-incubated with (S)-alpha-chlorohydrin did not maintain ATP levels, evolved less carbon dioxide and produced dihydroxyacetone phosphate. Assays of incubates in which fructose-1,6-bisphosphate was used as the substrate showed the presence of equilibrium quantities of fructose-6-phosphate and glucose-6-phosphate which were not detected when either fructose or glucose were used as substrates. [14C]Fructose and [14C]glucose were not produced from [14C]fructose-1,6-bisphosphate in spermatozoal incubates which had or had not been pre-incubated with (S)-alpha-chlorohydrin. Evidence is presented that a high concentration of fructose-1,6-bisphosphate leads to the formation of fructose-6-phosphate and glucose-6-phosphate but not of fructose and/or glucose.

Substrates for endogenous metabolism by mature boar spermatozoa

Reproduction ◽  
2000 ◽  
pp. 129-135 ◽  
Author(s):  
AR Jones ◽  
WA Bubb
Keyword(s):  
Energy Charge ◽  
High Energy ◽  
Glycolytic Pathway ◽  
Membrane Phospholipids ◽  
Atp Production ◽  
Metabolic Studies ◽  
Metabolic Substrates ◽  
Charge Potential ◽  
Endogenous Compounds ◽  
Boar Spermatozoa

Washed boar spermatozoa incubated in the absence of exogenous substrates maintained a high energy charge potential (ECP) for at least 10 h. Addition of bromopyruvate, an inhibitor of stage 2 of the glycolytic pathway, at any time during the incubation caused an immediate decrease in the ECP, indicating that the mobilization of endogenous compounds requires this section of the pathway for the production of lactate, the major mitochondrial substrate for ATP production. Some of the sources of the metabolic substrates have been identified, by NMR and metabolic studies, as di- or triglycerides, to produce glycerol, and membrane phospholipids for the production of glycerol 3-phosphate. Acetylcarnitine contributes acetyl groups early in the incubation; glycerylphosphorylcholine is degraded to glycerol 3-phosphate and choline after about 5 h, and acetate also accumulates after about 5 h. The presence of phosphorylcholine and phosphorylethanolamine later in the incubation indicates that phospholipids are also degraded to glycerol.

scholarly journals Erythrocyte glycolysis and its marked alterations by muscular exercise in type VII glycogenosis

Blood ◽  
1988 ◽  
Vol 71 (4) ◽  
pp. 1130-1134
Author(s):  
T Shimizu ◽  
N Kono ◽  
H Kiyokawa ◽  
Y Yamada ◽  
N Hara ◽  
...  
Keyword(s):  
Bed Rest ◽  
Normal Subjects ◽  
Dihydroxyacetone Phosphate ◽  
Crossover Point ◽  
Control Value ◽  
Myogenic Factors ◽  
Fructose 1,6 Bisphosphate ◽  
2,3 Dpg ◽  
Ergometric Exercise

Levels of erythrocyte glycolytic intermediates after the phosphofructokinase (PFK) step, including 2,3-bisphosphoglycerate (2,3- DPG), were decreased at rest in patients from separate families with type VII glycogenosis. The concentration of 2,3-DPG was about half of the normal control value during a period of unrestricted daily activity but was further decreased to one third of normal after a one-day bed rest. Mild ergometric exercise rapidly increased the levels of fructose- 1,6-bisphosphate, dihydroxyacetone phosphate plus glyceraldehyde-3- phosphate, and 2,3-DPG in patients' circulating erythrocytes but did not in those of normal subjects. This indicated that a crossover point at the PFK step in glycolysis disappeared after physical exercise and, consequently, the 2,3-DPG concentration, which had decreased because of blockage of the PFK step, was restored considerably. This apparently exercise-related alteration in intermediary metabolism at the beginning of glycolysis was reproduced in vitro by incubating normal erythrocytes in the presence of inosine or ammonia, both of which have increased levels in circulating blood during and after exercise in this disorder. We conclude that physical activity in addition to a genetic deficiency in erythrocyte PFK affects glycolysis in erythrocytes in type VII glycogenosis and that myogenic factors released from exercising muscles may be responsible for this change.

Suppression of epididymal sperm antigenicity in the rabbit by uteroglobin and transglutaminase in vitro

Science ◽  
1983 ◽  
Vol 219 (4587) ◽  
pp. 989-991 ◽  
Author(s):  
D. Mukherjee ◽  
A. Agrawal ◽  
R Manjunath ◽  
A. Mukherjee
Keyword(s):  
Epididymal Sperm
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