N-Acetylglucosaminyltransferase Activity in Liver, Serum, and Ovaries of Domestic Fowl

1971 ◽  
Vol 49 (6) ◽  
pp. 671-675 ◽  
Author(s):  
D. A. Gornall ◽  
A. Kuksis ◽  
L. Pinteric ◽  
Sailen Mookerjea
Keyword(s):  
Enzyme Activity ◽  
Enzyme Activities ◽  
Domestic Fowl ◽  
Cellular Membrane ◽  
Laying Hen ◽  
Assay System ◽  
Liver Homogenates ◽  
Low Levels ◽  
Increased Activity

Homogenates of the liver, serum, and ovaries of the laying hen and the liver and serum of the immature pullet were examined for N-acetylglucosaminyltransferase activity. The activity in the liver homogenates was higher in the laying hen than in the pullet while their sera showed similar low levels of enzyme activity. The homogenate of the ovary from the laying hen was also found to contain N-acetylglucos-aminyltransferase. Golgi-rich and Golgi-depleted membrane fractions were prepared from the liver homogenates of both types of fowl and examined in the assay system. The Golgi-depleted membrane fractions from the livers of both laying hen and pullet had higher enzyme activities than the corresponding Golgi-rich fractions. The N-acetylglucosaminyltransferase activities in both cellular membrane fractions were higher in the laying hen than in the pullet. The results are compatible with the hypothesis that N-acetylglucosaminyltransferase is involved in synthesis of lipoproteins and/or glycoproteins by the liver and the ovary. In contrast to the rat, the hen enzyme did not show increased activity in the presence of added CDP-choline.

Changes in 3β-hydroxy-Δ5-steroid dehydrogenase activity in granulosa tissue during the ovulatory cycle of the laying hen (Gallus domesticus)

1985 ◽  
Vol 106 (3) ◽  
pp. 269-273 ◽  
Author(s):  
D. G. Armstrong
Keyword(s):  
Enzyme Activity ◽  
Dehydrogenase Activity ◽  
Domestic Fowl ◽  
Ovarian Follicle ◽  
Laying Hen ◽  
Gallus Domesticus ◽  
Ovulatory Cycle ◽  
Lh Surge ◽  
Maximal Plasma ◽  
Steroid Dehydrogenase

ABSTRACT The object of this study was to examine changes in the activity of granulosa 3β-hydroxy-Δ5-steroid dehydrogenase during the ovulatory cycle of the domestic fowl. The enzyme activity in granulosa tissue from the largest follicle increased significantly during the period 8–14 h before an expected ovulation. The increase in activity occurs before the preovulatory surge of LH and near the time of lights off. During the 4–8 h period before an ovulation, i.e. the time of maximal plasma LH concentrations, 3β-hydroxy-Δ5-steroid dehydrogenase activity decreased in granulosa tissue from the largest follicle. This observation is explained by proposing that the enzyme is inhibited by the large amounts of progesterone found in the tissue at this time. The results indicate that important biochemical changes are taking place within granulosa tissue of the largest ovarian follicle before the preovulatory LH surge. J. Endocr. (1985) 106, 269–273

Effects of the herbicides fluometuron and prometryn on Rhizoctonia solani in soil cultures

1977 ◽  
Vol 23 (5) ◽  
pp. 617-623 ◽  
Author(s):  
H. Wayne Beam ◽  
E. A. Curl ◽  
R. Rodriguez-Kabana
Keyword(s):  
Enzyme Activity ◽  
Rhizoctonia Solani ◽  
Enzyme Activities ◽  
Soil Enzyme ◽  
Soil Enzyme Activity ◽  
Galactosidase Activity ◽  
Related Factors ◽  
Low Levels ◽  
Highly Correlated

Responses of Rhizoctonia solani to herbicides in soil cultures were assessed by measuring soil enzyme activity and other growth-related factors. Both β-galactosidase (EC 3.2.1.23) and phosphatase (EC 3.1.3.1, 3.1.3.2) activities were highly correlated with amounts of mycelium in soil. Both enzyme activities were reduced significantly by either fluometuron or prometryn at 40 μg/g of soil; the pathogen was more distinctly suppressed by fluometuron and showed a stronger tendency to overcome the effects of prometryn with time. Inhibition was also reflected in reduced utilization of glucose and less CO2-C evolved. Except for an increase in β-galactosidase activity in the presence of 1 μg fluometuron, low levels of either herbicide had little effect on the pathogen.

THE UPTAKE OF (6,7-3H) 17β-OESTRADIOL BY TISSUES OF THE DOMESTIC FOWL

1969 ◽  
Vol 60 (2) ◽  
pp. 199-209 ◽  
Author(s):  
R. A. Hawkins ◽  
P. J. Heald ◽  
Patricia Taylor
Keyword(s):  
Pituitary Gland ◽  
Intravenous Injection ◽  
Domestic Fowl ◽  
Physiological State ◽  
Laying Hen ◽  
Adult Bird

ABSTRACT A limited investigation of the distribution of radioactivity in the tissues of the adult laying hen has been made at differing times after intravenous injection of (6,7-3H) 17β-oestradiol. Uptake by all tissues examined was maximal between 2.0 and 4.0 minutes after injection. There was a marked retention of radioactivity by the oviduct and the liver. Of cerebral tissues examined the uptake of radioactivity was greatest in the pituitary gland. This uptake varied according to the physiological state of the bird. Calculations based on the rates of clearance of intravenous (6,7-3H) 17β-oestradiol indicate that in the adult bird the rate of secretion by the ovary is of the order of 1–2.0 mg oestradiol/24 h.

AN INCREASED RATE OF CHOLESTEROL BIOSYNTHESIS WITH MICROSOME FRACTIONS OF LIVER FROM KETOTIC GUINEA PIGS

1962 ◽  
Vol 40 (1) ◽  
pp. 1749-1762 ◽  
Author(s):  
F. Sauer
Keyword(s):  
Young Adult ◽  
Guinea Pigs ◽  
Cholesterol Synthesis ◽  
Cholesterol Biosynthesis ◽  
Maximum Activity ◽  
Sterol Synthesis ◽  
Differential Centrifugation ◽  
Microsome Fraction ◽  
Liver Homogenates ◽  
Increased Activity

Cholesterol synthesis was studied in liver fractions obtained by differential centrifugation from young, adult, and ketotic guinea pigs. Both 10,000 × g and 105,000 × g sediment was required for maximum activity. Incubations were carried out in the presence of appropriate liver fractions from young guinea pigs in order to overcome the low rates of cholesterol synthesis in liver homogenates from adult guinea pigs. Microsome fractions from ketotic hyperlipemic guinea pigs actively promoted sterol synthesis when incubated with mitochondria plus supernatant from young guinea pigs, while microsome fractions from adult controls (fed or starved) decreased the rate of sterol synthesis in the same incubation system. The results of this investigation indicate that microsomes from hyperlipemic ketotic guinea pigs do not have a block in cholesterol synthesis characteristic of microsomes from starved animals, and that this microsome fraction has increased activity of HMG-CoA2reductase, one of the key enzymes of cholesterol synthesis.

scholarly journals Enzyme Histochemical Studies of Adipose Tissue in Porcine Yellow Fat Disease

1974 ◽  
Vol 11 (6) ◽  
pp. 465-476 ◽  
Author(s):  
L. H. J. C. Danse ◽  
W. A. Steenbergen-Botterweg
Keyword(s):  
Enzyme Activity ◽  
Adipose Tissue ◽  
Acid Phosphatase ◽  
Nonspecific Esterase ◽  
Cell Structures ◽  
Increased Activity

Adipose tissue of piglets with yellow fat disease had increased activity of nonspecific esterase, 5-nucleotidase, and acid phosphatase. Since these enzymes are associated with different cell structures and damage to these structures can result in increased enzyme activity, they are criteria for pathogenetic study of yellow fat disease.

scholarly journals Rat uterine microbiochemistry: metabolic enzyme activities stimulated by 17-beta-estradiol are localized in epithelial cells.

1987 ◽  
Vol 35 (6) ◽  
pp. 657-662 ◽  
Author(s):  
J P Holt ◽  
E Rhe
Keyword(s):  
Enzyme Activity ◽  
Smooth Muscle ◽  
Epithelial Cells ◽  
Dose Response ◽  
Enzyme Activities ◽  
Time Course ◽  
Citrate Synthase ◽  
Ovariectomized Rats ◽  
Similar Response ◽  
Estradiol Treatment

Lactate dehydrogenase (LDH; EC 1.1.1.27), citrate synthase (CS; EC 4.1.3.7), and beta-hydroxyacyl-CoA-dehydrogenase (beta-OH-acyl-CoA-DH; EC 1.1.1.35) activities were determined in each of the three major cell types of rat uterus, i.e., epithelial, stromal, and smooth muscle, using quantitative microanalytical techniques. Adult ovariectomized rats were treated with 17-beta-estradiol to determine the time course and dose response (0.025-50 micrograms/300-g rat) effect of estrogen on enzyme activity of each type of uterine cell. The use of "oil well" and enzyme-cycling microtechniques to determine the time course and the dose responses of enzyme activity changes required microassays involving 1595 microdissected single cell specimens. Estradiol treatment increased epithelial LDH, CS and beta-OH-acyl-CoA-DH activity but had no effect on these enzymes in the stroma or in smooth muscle cells. The estradiol-stimulated peak enzyme activities on Day 4 in the intervention group are compared with those in the ovariectomized rat controls as follows: LDH, 44.5 +/- 3.5 vs 22.3 +/- 3.9; CS, 3.5 +/- 0.2 vs 1.5 +/- 0.6; beta-OH-acyl-CoA-H, 3.5 +/- 0.32 vs 2.2 +/- 0.2 (mean +/- standard deviation; mol/kg/hr). Stromal cell activities (LDH, 7.4 +/- 1.0; CS, 1.2 +/- 0.2; beta-OH-acyl-CoA-DH, 0.9 +/- 0.1) were significantly lower than epithelial cell levels and were similar to smooth muscle levels. Therefore, even in the ovariectomized animal epithelial cells have markedly higher metabolic activity compared with adjacent cells. The enzyme activities are expressed as moles of substrate reacting per kilogram of dry weight per hour. All three enzymes exhibited a 17-beta-estradiol-induced dose response between 0.025-0.15 micrograms/300-g rat. The three enzymes studied all had similar response patterns to estrogen. The effect of estradiol was restricted to epithelial cells, with enzyme activities increasing to maximal levels after approximately 96 hr of hormone treatment. This study therefore not only confirms the specific and differential metabolic responses of uterine cells to estradiol treatment, but clearly demonstrates that marked metabolic differences exist between epithelial cells and stromal or smooth muscle uterine cells.

Change Analysis of Enzyme Activity under Different Conditions of Film Remnant in Soil

2012 ◽  
Vol 518-523 ◽  
pp. 39-43
Author(s):  
Xiao Guang Zhao ◽  
Yuan Yuan Guan ◽  
Wen Yu Huang
Keyword(s):  
Enzyme Activity ◽  
Enzyme Activities ◽  
Scientific Basis ◽  
Soil Enzyme ◽  
Soil Microorganism ◽  
Soil Enzyme Activities ◽  
Change Analysis ◽  
Soil Material ◽  
The Relationship

In this paper, simulated experiments were performed in pots by using soil materials in different conditions of film remnant. Based on the research on soil microorganism quantity trends of soil enzyme activities were analyzed systematically: soil without film remnant, soil with film remnant for 5, 10, 15 and 20 years. By analyzing crop progress, the relationship with soil material was studied, in order to provide scientific basis for the variation laws between different conditions of film remnant and the activity of soil enzyme.

scholarly journals Enzymic transfer of glucose and xylose from uridine diphosphate glucose and uridine diphosphate xylose to bilirubin by untreated and digitonin-activated preparations from rat liver

1972 ◽  
Vol 129 (3) ◽  
pp. 619-633 ◽  
Author(s):  
J. Fevery ◽  
P. Leroy ◽  
K. P. M. Heirwegh
Keyword(s):  
Enzyme Activities ◽  
Metal Ion ◽  
Glucuronic Acid ◽  
Uridine Diphosphate ◽  
No Formation ◽  
Cell Extracts ◽  
Straight Line ◽  
Standard Assay ◽  
Diphosphate Glucose ◽  
Liver Homogenates

1. Digitonin-treated and untreated homogenates, cell extracts and washed microsomal preparations from liver of Wistar R rats are capable of transferring sugar from UDP-glucose or UDP-xylose to bilirubin. No formation of bilirubin glycosides occurred with UDP-galactose or d-glucose, d-xylose or d-glucuronic acid as the sources of sugar. 2. Procedures to assay digitonin-activated and unactivated bilirubin UDP-glucosyltransferase and bilirubin UDP-xylosyltransferase were developed. 3. In digitonin-activated microsomal preparations the transferring enzymes had the following properties. Both enzyme activities were increased 2.5-fold by pretreatment with digitonin. They were optimum at pH6.6–7.2. Michaelis–Menten kinetics were followed with respect to UDP-glucose. In contrast, double-reciprocal plots of enzyme activity against the concentration of UDP-xylose showed two intersecting straight-line sections corresponding to concentration ranges where either bilirubin monoxyloside was formed (at low UDP-xylose concentrations) or where mixtures of both the mono- and di-xyloside were synthesized (at high UDP-xylose concentrations). Both enzyme activities were stimulated by Mg2+; Ca2+ was slightly less, and Mn2+ slightly more, stimulatory than Mg2+. Of the activities found in standard assay systems containing Mg2+, 58–78% (substrate UDP-glucose) and 0–38% (substrate UDP-xylose) were independent of added bivalent metal ion. Double-reciprocal plots of the Mg2+-dependent activities against the concentration of added Mg2+ were linear. 4. In comparative experiments the relative activities of liver homogenates obtained with UDP-glucuronic acid, UDP-glucose and UDP-xylose were 1:1.5:2.7 for untreated preparations and 1:0.29:0.44 after activation with digitonin. 5. Bilirubin UDP-glucuronyltransferase was protected against denaturation by human serum albumin, whereas bilirubin UDP-xylosyltransferase was not. 6. Digitonin-treated and untreated liver homogenates from Gunn rats were inactive in transferring sugar to bilirubin from UDP-glucuronic acid (in agreement with the work of others), UDP-glucose or UDP-xylose.

scholarly journals Interaction of soluble glucosyl- and mannosyl-transferase enzyme activities in the synthesis of a glucomannan

1972 ◽  
Vol 129 (3) ◽  
pp. 645-655 ◽  
Author(s):  
J. S. Heller ◽  
C. L. Villemez
Keyword(s):  
Enzyme Activity ◽  
Enzyme Activities ◽  
Enzyme Preparation ◽  
The Other ◽  
Acceptor Molecule ◽  
Soluble Enzyme ◽  
Phaseolus Aureus ◽  
Polymeric Product ◽  
Sugar Nucleotide ◽  
Solubilized Enzyme

A neutral-detergent-solubilized-enzyme preparation derived from Phaseolus aureus hypocotyls contains two types of glycosyltransferase activity. One, mannosyltransferase enzyme activity, utilizes GDP-α-d-mannose as the sugar nucleotide substrate. The other, glucosyltransferase enzyme activity, utilizes GDP-α-d-glucose as the sugar nucleotide substrate. The soluble enzyme preparation catalyses the formation of what appears to be a homopolysaccharide when either sugar nucleotide is the only substrate present. A β-(1→4)-linked mannan is the only polymeric product when only GDP-α-d-mannose is added. A β-(1→4)-linked glucan is the only polymeric product when only GDP-α-d-glucose is added. In the presence of both sugar nucleotides, however, a β-(1→4)-linked glucomannan is formed. There are indications that endogenous sugar donors may be present in the enzyme preparation. There appear to be only two glycosyltransferases in the enzyme preparation, each catalysing the transfer of a different sugar to the same type of acceptor molecule. The glucosyltransferase requires the continual production of mannose-containing acceptor molecules for maintenance of enzyme activity, and is thereby dependent upon the activity of the mannosyltransferase. The mannosyltransferase, on the other hand, does not require the continual production of glucose-containing acceptors for maintenance of enzyme activity, but is severely inhibited by GDP-α-P-glucose. These properties promote the synthesis of β-(1→4)-linked glucomannan rather than β-(1→4)-linked glucan plus β-(1→4)-linked mannan when both sugar nucleotide substrates are present.

scholarly journals Establishment of a Gastric Cell-Based Assay System for Exploring Inhibitors of Octanoylated Ghrelin Production

2013 ◽  
Vol 18 (9) ◽  
pp. 1035-1042 ◽  
Author(s):  
Shigeru Oiso ◽  
Miyuki Nobe ◽  
Yuhei Yamaguchi ◽  
Shigeru Umemoto ◽  
Kazuo Nakamura ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Butyric Acid ◽  
Posttranslational Modification ◽  
Culture Medium ◽  
Octanoic Acid ◽  
Assay System ◽  
Heptanoic Acid ◽  
Ags Cells ◽  
Gastric Cell ◽  
Low Levels

Ghrelin, a gastric hormone, is a growth hormone-releasing peptide. Its serine-3 acylation with octanoic acid is essential for its orexigenic activity, and therefore, inhibition of the acylation of ghrelin may help in decreasing appetite and preventing obesity. This study aimed to establish a human gastric cell-based assay system to evaluate candidate inhibitors of octanoylated ghrelin production. In human gastric carcinoma AGS cells, obligatory factors for the posttranslational modification of ghrelin, such as certain prohormone convertases responsible for processing of proghrelin to the mature ghrelin and the enzyme-catalyzing acyl-modification of ghrelin, were well expressed, but ghrelin was expressed at low levels. Accordingly, we transfected a ghrelin-expressing vector into AGS cells and isolated a stable ghrelin-expressing cell line (AGS-GHRL8). AGS-GHRL8 cells secreted octanoylated ghrelin in accordance with the concentrations of octanoic acid in the culture medium. Given that ingested heptanoic acid is used for the acyl-modification of ghrelin, we evaluated whether heptanoic acid inhibits production of octanoylated ghrelin in AGS-GHRL8 cells. Butyric acid was used as a control. Indeed, heptanoic acid predictably decreased the secretion of octanoylated ghrelin, whereas butyric acid did not. The AGS-GHRL8 line established in this study will facilitate the screening of inhibitors of octanoylated ghrelin production.

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