THE NUTRITION OF VIBRIO COSTICOLUS: II. CYST(E)INE UTILIZATION

1964 ◽  
Vol 10 (2) ◽  
pp. 235-242
Author(s):  
W. L. Flannery ◽  
S. N. Durio
Keyword(s):  
Sodium Chloride ◽  
Citric Acid ◽  
Oxygen Uptake ◽  
Hydrogen Sulphide ◽  
Pyruvic Acid ◽  
Citric Acid Cycle ◽  
Chloride Concentration ◽  
Sodium Chloride Concentration ◽  
Acid Cycle ◽  
Essential Nutrient

The effect of cyst(e)ine and sodium chloride concentration on oxygen uptake, and hydrogen sulphide, ammonia, and pyruvic acid production by Vibrio costicolus is described. Added pyridoxal was unnecessary for maximum desulphydrase activity. Generally, oxidation curves of cyst(e)ine concentrations 4 μM or less were the customary type whereas curves which resulted from the oxidation of 6.25 μM cyst(e}ine and greater were of a type indicating accumulation of a product toxic to the system. This occurred in the presence of 1 M NaCl and the suppressed type of oxidation could be returned to normal by increasing the concentration of NaCl. Pyruvic acid accumulated in the flasks showing the suppressed type of oxidation curves, but did not accumulate in flasks showing customary oxidation curves. Pyruvic acid did not accumulate in flasks containing 6.25 μM cyst(e)ine if the sodium chloride concentration was increased to 1.5 M or greater. Pyruvic acid did accumulate with 3.125 μM cyst(e)ine if a citric acid cycle inhibitor (sodium fluoroacetate) was added to the flask contents. These studies suggest that the most likely pathway for the utilization of cyst(e)ine, an essential nutrient for V. costicolus, is its conversion to pyruvate to enter the citric acid cycle.

scholarly journals Citrus Flavanones Affect Hepatic Fatty Acid Oxidation in Rats by Acting as Prooxidant Agents

2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Rodrigo Polimeni Constantin ◽  
Gilson Soares do Nascimento ◽  
Renato Polimeni Constantin ◽  
Clairce Luzia Salgueiro ◽  
Adelar Bracht ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Citric Acid ◽  
Oxygen Uptake ◽  
Fatty Acid Oxidation ◽  
Citric Acid Cycle ◽  
Acid Oxidation ◽  
Acid Cycle ◽  
Hepatic Fatty Acid ◽  
Wide Range ◽  
Hepatic Fatty Acid Oxidation

Citrus flavonoids have a wide range of biological activities and positive health effects on mammalian cells because of their antioxidant properties. However, they also act as prooxidants and thus may interfere with metabolic pathways. The purpose of this work was to evaluate the effects of three citrus flavanones, hesperidin, hesperetin, and naringenin, on several parameters linked to fatty acid oxidation in mitochondria, peroxisomes, and perfused livers of rats. When exogenous octanoate was used as substrate, hesperetin and naringenin reduced the mitochondrial NADH/NAD+ratio and stimulated the citric acid cycle without significant changes on oxygen uptake or ketogenesis. When fatty acid oxidation from endogenous sources was evaluated, hesperetin and naringenin strongly reduced the mitochondrial NADH/NAD+ratio. They also inhibited both oxygen uptake and ketogenesis and stimulated the citric acid cycle. Hesperidin, on the other hand, had little to no effect on these parameters. These results confirm the hypothesis that citrus flavanones are able to induce a more oxidised state in liver cells, altering parameters related to hepatic fatty acid oxidation. The prooxidant effect is most likely a consequence of the ability of these substances to oxidise NADH upon production of phenoxyl radicals in the presence of peroxidases and hydrogen peroxide.

scholarly journals Metabolism of Semen After Freezing [[ . The Aerobic Metabolism of Ram Spermatozoa Before and After Storage at ?79°C

1969 ◽  
Vol 22 (3) ◽  
pp. 733
Author(s):  
T O'shea
Keyword(s):  
Citric Acid ◽  
Oxygen Uptake ◽  
Sodium Acetate ◽  
Citric Acid Cycle ◽  
Cell Metabolism ◽  
Sodium Lactate ◽  
Aerobic Metabolism ◽  
Sodium Salts ◽  
Acid Cycle ◽  
Before And After

The metabolism of ram spermatozoa, incubated at 37�0 shortly after ejacula-tion and after storage overnight at -79�0, was examined using various combinations of fructose, sodium lactate, sodium acetate, and sodium salts of citric acid cycle intermediates. Although freezing depressed all indices of cell metabolism, there were few qualitative differences between the metabolism by fresh or thawed semen of the various substrates. The increased oxygen uptake of thawed spermatozoa on addition of succinate was unrelated to motility and to other parameters of metabolism.

PATHWAYS OF CARBOHYDRATE METABOLISM IN LOBSTER HEPATOPANCREAS

1962 ◽  
Vol 40 (8) ◽  
pp. 1043-1050 ◽  
Author(s):  
P. W. Hochachka ◽  
J. M. Teal ◽  
M. Telford
Keyword(s):  
Citric Acid ◽  
Oxygen Uptake ◽  
Carbohydrate Metabolism ◽  
Citric Acid Cycle ◽  
The Other ◽  
Short Term ◽  
Acid Cycle

Oxygen uptake by homogenates of lobster hepatopancreas was stimulated by the addition of Embden–Meyerhof, pentose cycle, and citric acid cycle intermediates as well as xylose. Acetate-1-C14oxidation was blocked by fluoracetate and glucose-1-C14oxidation fell by 80% with iodoacetate treatment. TPN and DPN increased glucose-1-C14oxidation by 140% and 20% and acetate-1-C14oxidation by 50% and 100% respectively. Large amounts of C14enter polysaccharide following treatment with glucose-1-C14or acetate-1-C14but very little enters after treatment with the same amount of gluconate-1-C14. Gluconate and xylose oxidation occurs in mitochondria-free preparations. In short-term tests with acetate-1-C14as substrate, most of the label in glycogen is on carbons 3 and 4 and the amount in the other positions can be explained on the basis of a 5–10% participation of the pentose cycle.

PATHWAYS OF CARBOHYDRATE METABOLISM IN LOBSTER HEPATOPANCREAS

1962 ◽  
Vol 40 (1) ◽  
pp. 1043-1050 ◽  
Author(s):  
P. W. Hochachka ◽  
J. M. Teal ◽  
M. Telford
Keyword(s):  
Citric Acid ◽  
Oxygen Uptake ◽  
Carbohydrate Metabolism ◽  
Citric Acid Cycle ◽  
The Other ◽  
Short Term ◽  
Acid Cycle

Oxygen uptake by homogenates of lobster hepatopancreas was stimulated by the addition of Embden–Meyerhof, pentose cycle, and citric acid cycle intermediates as well as xylose. Acetate-1-C14oxidation was blocked by fluoracetate and glucose-1-C14oxidation fell by 80% with iodoacetate treatment. TPN and DPN increased glucose-1-C14oxidation by 140% and 20% and acetate-1-C14oxidation by 50% and 100% respectively. Large amounts of C14enter polysaccharide following treatment with glucose-1-C14or acetate-1-C14but very little enters after treatment with the same amount of gluconate-1-C14. Gluconate and xylose oxidation occurs in mitochondria-free preparations. In short-term tests with acetate-1-C14as substrate, most of the label in glycogen is on carbons 3 and 4 and the amount in the other positions can be explained on the basis of a 5–10% participation of the pentose cycle.

EFFECT OF SERUM GONADOTROPHIN ON DEHYDROGENASES OF THE CITRIC ACID CYCLE IN THE OVARY OF THE RAT

1963 ◽  
Vol 42 (4) ◽  
pp. 480-484 ◽  
Author(s):  
B. Eckstein ◽  
R. Landsberg
Keyword(s):  
Citric Acid ◽  
Citric Acid Cycle ◽  
Age Groups ◽  
Succinic Dehydrogenase ◽  
Immature Rat ◽  
Acid Cycle ◽  
Immature Rats ◽  
Rat Ovary

ABSTRACT The succinic, malic and isocitric dehydrogenases in the ovary of immature and mature, normal and serum gonadotrophin injected rats were examined. The Qo2 of these enzymes were markedly enhanced in the gonadotrophin injected rats of both age groups, except in the case of succinic dehydrogenase in the ovary of the immature rats, where a slight non-significant decrease was noted. It is concluded that in the mature rat ovary, gonadotrophin administration stimulates the activity of all the examined dehydrogenases of the citric acid cycle, whereas in the immature rat ovary, at least the isocitric- and malic dehydrogenases are thus stimulated.

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