Effect of Feeding and of DDT on the Activity of Hepatic Glucose 6-Phosphate Dehydrogenase in Two Salmonids

1969 ◽  
Vol 26 (12) ◽  
pp. 3209-3216 ◽  
Author(s):  
Donald R. Buhler ◽  
P. Benville
Keyword(s):  
Rainbow Trout ◽  
Coho Salmon ◽  
Specific Activity ◽  
Enzyme System ◽  
Regulatory Control ◽  
Hepatic Glucose ◽  
Dehydrogenase Enzyme ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Effect Of Feeding

The specific activity of liver glucose 6-phosphate dehydrogenase in yearling rainbow trout remained unchanged when the fish were starved for periods as long as 8 weeks and when starved animals were fed diets of various compositions. Injection of insulin concurrently with refeeding also failed to alter the specific activity of the enzyme in trout. The absence of a dietary or insulin influence on the teleost enzyme system is to be contrasted with studies in mammals in which the activity of hepatic glucose 6-P dehydrogenase was markedly stimulated after refeeding starved animals or injection of insulin.Ingestion of the pesticide DDT by juvenile coho salmon or adult rainbow trout also had no effect on the specific activity of liver glucose 6-P dehydrogenase and DDT failed to inhibit the rainbow trout enzyme in vitro. These results also differ considerably from those found in higher animals.These results suggest that the glucose 6-P dehydrogenase enzyme in teleosts may be under a different type of regulatory control from that found in mammals.

The Effects of Some Antibiotics on Sheep Lens Glucose 6-Phosphate Dehydrogenase in Vitro

2003 ◽  
Vol 13 (2) ◽  
pp. 155-161 ◽  
Author(s):  
Ş. Beydemir ◽  
D.N. Kulaçoğlu ◽  
M. Çiftçi ◽  
Ö.I. Küfrevioğlu
Keyword(s):  
Specific Activity ◽  
Gentamicin Sulfate ◽  
Vancomycin Hydrochloride ◽  
Dehydrogenase Enzyme ◽  
Postmortem Studies ◽  
Cefazolin Sodium ◽  
In Vitro Effects ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Sepharose 4B

Purpose To investigate the in vitro effects of gentamicin sulfate, vancomycin hydrochloride, sodium cefazolin and ceftriaxone on glucose 6-phosphate dehydrogenase enzyme (G6PD) purified from sheep lenses. Methods G6PD was purified from sheep lenses with a yield of 66.8% and a specific activity of 7.8 U/mg proteins, and 10,400-fold using ammonium sulfate fractionation and 2′,5′-ADP Sepharose 4B affinity gel. The enzyme activity was determined by Beutler's method. Results Gentamicin sulfate and vancomycin hydrochloride strongly inhibited the enzyme in vitro. The concentrations causing 50% inhibition (IC50) were 15.34, and 8.0 mM, respectively. Conversely, cefazolin sodium strongly activated this enzyme, and ceftriaxone caused milder activation. Conclusions If a patient with G6PD deficiency requires gentamicin sulfate or vancomycin hydrochloride, routine ophthalmic did not inhibit this enzyme. Postmortem studies are now needed to investigate the activity of G6PD and how it is affected by these antibiotics.

CONVERSION OF PREGNENOLONE TO PROGESTERONE BY RABBIT PLACENTA IN VITRO

1969 ◽  
Vol 61 (4) ◽  
pp. 577-584 ◽  
Author(s):  
K. Matsumoto ◽  
G. Yamane ◽  
H. Endo ◽  
K. Kotoh ◽  
K. Okano
Keyword(s):  
Isotope Dilution ◽  
Specific Activity ◽  
Enzyme System ◽  
Hydroxysteroid Dehydrogenase ◽  
Pregnant Rabbit ◽  
Dehydrogenase Enzyme ◽  
Constant Specific Activity

ABSTRACT A placental preparation from rabbits in mid-pregnancy was shown to convert 7α-3H-pregnenolone to radioactive progesterone in vitro. The extent of conversion per gram tissue by the placenta was about one hundredth of that by the ovary from the pregnant rabbit. Identification of radioactive progesterone was accomplished by reverse isotope dilution and recrystallization to constant specific activity. However, no Δ5-3β-hydroxysteroid dehydrogenase was found histochemically in the trophoblast and other tissues of the rabbit placenta. No ability to convert 7α-3H-pregnenolone to radioactive 20α-hydroxypregn-4-en-3-one, 20β-hydroxypregn-4-en-3-one, corticosterone, cortisol, androst-4-ene-3,17-dione, dehydroepiandrosterone, 17β-oestradiol and oestrone in placental preparation from rabbits could be demonstrated. The data demonstrate the presence of a 3β-ol-dehydrogenase enzyme system in the rabbit placenta.

Conversion of Flavanone to Flavone, Dihydroflavonol and Flavonol with an Enzyme System from Cell Cultures of Parsley

1981 ◽  
Vol 36 (9-10) ◽  
pp. 742-750 ◽  
Author(s):  
L. Britsch ◽  
W. Heller ◽  
H. Grisebach
Keyword(s):  
Microsomal Fraction ◽  
Specific Activity ◽  
Enzyme System ◽  
High Specific Activity ◽  
Cell Suspension Cultures ◽  
Soluble Enzyme ◽  
Enzyme Preparations ◽  
Malonyl Coa ◽  
In Vitro Biosynthesis

Abstract Soluble enzyme preparations from irradiated cell suspension cultures of parsley (Petroselinum hortense Hoffm.) catalyse the conversion of flavanone to flavone, dihydroflavonol and flavonol. These reactions require 2-oxoglutarate, Fe2+ and ascorbate as cofactors. In the presence of these cofactors conversion of dihydroflavonol to flavonol was also observed. With this system in vitro biosynthesis of radioactive flavone, dihydroflavonol and flavonol from [2-14C]malonyl-CoA and 4-coumaroyl-CoA in good yield and with high specific activity is possible.We postulate that synthesis of flavone and flavonol from flavanone proceeds via 2-hydroxy-and 2,3-dihydroxyflavanone, respectively, with subsequent dehydration.The microsomal fraction of the parsley cells contains an NADPH-dependent flavanone 3'-hydroxylase.

scholarly journals Effects of some antibiotics on glucose 6-phosphate dehydrogenase in sheep liver

2012 ◽  
Vol 47 (No. 10 - 11) ◽  
pp. 283-288 ◽  
Author(s):  
M. Çiftci ◽  
V. Turkoglu ◽  
S. Aldemir
Keyword(s):  
Gel Electrophoresis ◽  
Enzyme Purification ◽  
Specific Activity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sheep Liver ◽  
Sds Page ◽  
In Vitro Effects ◽  
Glucose 6 Phosphate Dehydrogenase ◽  
Sepharose 4B

In vitro effects of penicillin, sulbactam, cefazolin, and amikacine on the activity of the enzyme glucose-6-phosphate dehydrogenase in sheep liver were investigated. Glucose 6-phosphate dehydrogenase was purified from sheep liver, using a simple and rapid method. The purification consisted of two steps, preparation of homogenate and 2’, 5’-ADP Sepharose 4B affinity chromatography. As a result of the two consecutive procedures, the enzyme, having the specific activity of 11.76 EU/mg proteins, was purified with a yield of 35.72% and 1.913 fold. In order to control the enzyme purification SDS polyacrylamide gel electrophoresis (SDS-PAGE) was done. SDS-PAGE showed a single band for the enzyme. In addition, I50 values of the antibiotics were determined by plotting activity % vs. antibiotic concentrations. I50 values were 17.71 mM for penicillin, 27.38 mM for sulbactam, 28.88 mM for cefazolin, and 30.59 mM for amikacine.

A Leukocytolytic Factor Isolated from Cultures of Aeromonas salmonicida

1977 ◽  
Vol 34 (8) ◽  
pp. 1118-1125 ◽  
Author(s):  
D. W. Fuller ◽  
K. S. Pilcher ◽  
J. L. Fryer
Keyword(s):  
Rainbow Trout ◽  
Virulence Factors ◽  
Coho Salmon ◽  
Virulent Strain ◽  
Deae Cellulose ◽  
Aeromonas Salmonicida ◽  
Salmo Gairdneri ◽  
Amino Sugars ◽  
Avirulent Strain

A substance characterized as a glycoprotein, isolated from the supernatant fluids of broth cultures of Aeromonas salmonicida by a combination of ammonium sulfate and ethanol precipitations followed by chromatography on DEAE-cellulose, was cytolytic for rainbow trout (Salmo gairdneri) leukocytes, and antigenic when injected into rabbits. The ratio of protein to hexose determined by analysis of the purified fraction was between 0.35 and 0.45, and small amounts of amino sugars were detected. A virulent strain of A. salmonicida produced much more of this factor than an avirulent strain. This factor was cytolytic for leukocytes in vitro and also produced a pronounced leukopenia when injected intravenously in adult rainbow trout. When injected in small coho salmon (Oncorhyncus kisutch) 8–13 cm long together with about one LD50 of live A. salmonicida 36 of 40 fish succumbed to the combination, whereas only 14 of 40 died from an injection of the bacterium alone. Thus, the pathogenicity of the organism was enhanced, presumably by increasing the susceptibility of the host. Hence, this glycoprotein apparently is one of the virulence factors of this bacterium. Key words: leukocytolytic factor, Aeromonas salmonicida, glycoprotein, virulence factor

scholarly journals Activity of key enzymes involved in glucose and triglyceride catabolism during bovine oocyte maturation in vitro

Reproduction ◽  
2002 ◽  
pp. 675-681 ◽  
Author(s):  
P Cetica ◽  
L Pintos ◽  
G Dalvit ◽  
M Beconi
Keyword(s):  
Enzymatic Activity ◽  
Pentose Phosphate Pathway ◽  
In Vitro Maturation ◽  
Specific Activity ◽  
Lipolytic Activity ◽  
Cumulus Cells ◽  
Pentose Phosphate ◽  
Key Enzymes ◽  
Glucose 6 Phosphate Dehydrogenase

Little is known about the metabolic profile of cumulus-oocyte complexes (COCs) during maturation. The aim of this study was to determine the differential participation of enzymatic activity in cumulus cells and the oocyte during in vitro maturation of bovine oocytes, by measuring the activity of key enzymes involved in the regulation of glycolysis (phosphofructokinase), the pentose phosphate pathway (glucose-6-phosphate dehydrogenase) and lipolysis (lipase). COCs were matured in medium 199 plus 10% (v/v) steer serum for 22-24 h at 39 degrees C in 5% CO(2):95% humidified air. Phosphofructokinase, glucose-6-phosphate dehydrogenase and lipase activities were measured in immature and in vitro matured COCs, denuded oocytes and cumulus cells, respectively. Phosphofructokinase and glucose-6-phosphate dehydrogenase activities (enzymatic units) remained constant during in vitro maturation of COCs, but there was a significant decrease in lipase activity (units) (P < 0.05), as activity in cumulus cells decreased significantly (P < 0.05). For the three enzymes studied, enzyme activity (units) remained unchanged in the oocyte during in vitro maturation. Specific activity increased in the oocyte (P < 0.05) and decreased in cumulus cells as a result of maturation (P < 0.05). In cumulus cells, phosphofructokinase was the most abundant of the three enzymes followed by glucose-6-phosphate dehydrogenase and then lipase (P < 0.05), whereas in the denuded oocyte this order was reversed (P < 0.05). Thus, the metabolism of cumulus cells is adapted to control the flow of metabolites toward the oocyte, which maintains its enzymatic activity even when dissociated from cumulus cells during maturation. The high activity of phosphofructokinase in cumulus cells indicates that glucose is metabolized mainly via the glycolytic pathway in these cells. The greater relative activity of glucose-6-phosphate dehydrogenase recorded in the oocyte indicates that glucose uptake could be directed mainly toward the pentose phosphate pathway. The marked lipolytic activity concentrated in the oocyte indicates an active participation in lipid catabolism during maturation.

The Nature of Hepatic Cytochrome P-450 Induced in Hexachlorobenzene-Fed Rats

1978 ◽  
Vol 55 (5) ◽  
pp. 461-469
Author(s):  
G. H. Blekkenhorst ◽  
L. Eales ◽  
N. R. Pimstone
Keyword(s):  
Catalytic Properties ◽  
Enzyme System ◽  
Spectral Studies ◽  
Time Intervals ◽  
Female Wistar Rats ◽  
Kinetics Of ◽  
Cytochrome P 450 ◽  
Effect Of Feeding ◽  
Hepatic Cytochrome

1. The effect of feeding with a diet containing 0.2% (w/w) hexachlorobenzene on hepatic and urinary porphyrins and hepatic cytochrome P-450 was studied at various time intervals in female Wistar rats. 2. Hexachlorobenzene administration for 45 days resulted in the development of porphyria in rats, which biochemically closely resembles symptomatic porphyria in humans, with elevation of urinary uroporphyrin excretion, hepatic uroporphyrin content, and hepatic cytochrome P-450 content, in addition to appearance of porphyrins of the isocoproporphyrin (P1) series in the faeces. 3. Spectral studies of the induced hepatic cytochrome P-450 at 45 days with carbon monoxide and ethyl isocyanide as ligands indicated the presence of a greater admixture of a haemoprotein distinct from cytochrome P-450. 4. Study in vitro of the kinetics of two reactions, namely aminopyrine N-demethylation and 3,4-benzpyrene hydroxylation, catalysed by the hepatic microsomal cytochrome P-450-dependent enzyme system, suggested that hexachlorobenzene induced a form of cytochrome P-450 with different catalytic properties from those of forms induced by either phenobarbital or 3-methylcholanthrene.

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