scholarly journals A comparison of glucoside formation by liver preparations from the rabbit and the mouse

1974 ◽  
Vol 142 (1) ◽  
pp. 75-78 ◽  
Author(s):  
Rosalind S. Labow ◽  
Donald S. Layne
Keyword(s):  
Mouse Liver ◽  
The Other ◽  
Rabbit Liver ◽  
Ph Optimum ◽  
Liver Homogenates

Liver homogenates from mice and from rabbits transfer glucose from UDP-[6-3H]glucose, at pH7.0, to oestradiol-17α, oestradiol-17β, oestradiol-17α 3-glucuronide, p-nitrophenol and diethylstilboestrol. In the rabbit the phenolic steroids were better substrates than p-nitrophenol for the glucosyltransferase, whereas the reverse was true in the mouse. At pH8.0, rabbit liver, but not mouse liver, transferred glucose to oestradiol-17α 3-glucuronide in better yield than that at pH7.0. Evidence is presented for the presence of two glucosyltransferases in rabbit liver. One of these has a pH optimum at about 8.0, and is highly specific for oestradiol-17α 3-glucuronide, whereas the other, which has a pH optimum at about 7.0, is similar in this respect to the transferase in mouse liver.

Characterization of glycineN-methyltransferase from rabbit liver

2004 ◽  
Vol 82 (3) ◽  
pp. 369-374 ◽  
Author(s):  
Doris Kloor ◽  
Katrin Karnahl ◽  
Jost Kömpf
Keyword(s):  
Enzymatic Activity ◽  
Kinetic Data ◽  
Adenine Nucleotides ◽  
The Other ◽  
Rabbit Liver ◽  
Ph Optimum ◽  
Isolation And Purification ◽  
Endogenous Adenosine ◽  
Sds Page

The enzymatic properties of glycine N-methyltransferase from rabbit liver and the effects of endogenous adenosine nucleosides, nucleotides and methyltransferase inhibitors were investigated using a photometrical assay to detect sarcosine with o-dianisidine as a dye. After isolation and purification the denatured enzyme showed a two-banded pattern by SDS–PAGE. The enzyme was highly specific for its substrates with a pH-optimum at pH 8.6. Glycine N-methyltransferase exhibits Michaelis-Menten kinetics for its substrates, S-adenosylmethionine and glycine, respectively. The apparent Kmand Vmaxvalues were determined for both the substrates, the other substrate being present at saturating concentrations. The enzyme was strongly inhibited in the presence of S-adenosylhomocysteine, 3-deazaadenosine, and 5′-S-isobutylthio-5′-deoxyadenosine. All other inhibitors investigated, adenosine, 2′-deoxyadenosine, aciclovir, and 5′-N-ethylcarboxamidoadenosine were poor inhibitors of the methylation rection. Adenine nucleotides and vidarabin were without effect on the enzymatic activity. Based on the kinetic data glycine N-methyltransferase from rabbit liver exhibits appreciable activity at physiological S-adenosylmethionine and S-adenosylhomocysteine levels.Key words: glycine N-methyltransferase, S-adenosylhomocysteine, S-adenosylmethionine, sarcosine oxidase, peroxidase.

scholarly journals Detection of CMP-N-acetylneuraminic acid hydroxylase activity in fractionated mouse liver

1989 ◽  
Vol 263 (2) ◽  
pp. 355-363 ◽  
Author(s):  
L Shaw ◽  
R Schauer
Keyword(s):  
Submandibular Gland ◽  
Mouse Liver ◽  
High Speed ◽  
Metal Salts ◽  
Supernatant Fraction ◽  
Inhibitory Influence ◽  
Hydroxylase Activity ◽  
Acetylneuraminic Acid ◽  
Liver Homogenates ◽  
High Speed Supernatant

The finding that N-glycoloylneuraminic acid (Neu5Gc) in pig submandibular gland is synthesized by hydroxylation of the sugar nucleotide CMP-Neu5Ac [Shaw & Schauer (1988) Biol. Chem. Hoppe-Seyler 369, 477-486] prompted us to investigate further the biosynthesis of this sialic acid in mouse liver. Free [14C]Neu5Ac, CMP-[14C]Neu5Ac and [14C]Neu5Ac glycosidically bound by Gal alpha 2-3- and Gal alpha 2-6-GlcNAc beta 1-4 linkages to fetuin were employed as potential substrates in experiments with fractionated mouse liver homogenates. The only substrate to be hydroxylated was the CMP-Neu5Ac glycoside. The product of the reaction was identified by chemical and enzymic methods as CMP-Neu5Gc. All of the CMP-Neu5Ac hydroxylase activity was detected in the high-speed supernatant fraction. The hydroxylase required a reduced nicotinamide nucleotide [NAD(P)H] coenzyme and molecular oxygen for activity. Furthermore, the activity of this enzyme was enhanced by exogenously added Fe2+ or Fe3+ ions, all other metal salts tested having a negligible or inhibitory influence. This hydroxylase is therefore tentatively classified as a monooxygenase. The cofactor requirement and CMP-Neu5Ac substrate specificity are identical to those of the enzyme in high-speed supernatants of pig submandibular gland, suggesting that this is a common route of Neu5Gc biosynthesis. The relevance of these results to the regulation of Neu5Gc expression in sialoglycoconjugates is discussed.

scholarly journals The fractionation of nuclei from mammalian cells by zonal centrifugation

1968 ◽  
Vol 109 (1) ◽  
pp. 127-135 ◽  
Author(s):  
I R Johnston ◽  
A P Mathias ◽  
F. Pennington ◽  
D. Ridge
Keyword(s):  
Rat Liver ◽  
Mammalian Cells ◽  
Mouse Liver ◽  
The Other ◽  
Slow Speed ◽  
Adult Rats ◽  
Sucrose Solutions ◽  
Liver Nuclei ◽  
Effect Of Age ◽  
Zonal Rotor

1. Purified liver nuclei from adult rats separate into two main zones when centrifuged in the slow-speed zonal rotor. One zone contains diploid nuclei, the other tetraploid. 2. The effect of age on the pattern of rat liver ploidy was examined. Tetraploid nuclei are virtually absent from young animals. They increase in proportion steadily with age. Partial hepatectomy disturbs the pattern of ploidy. 3. The zonal centrifuge permits the separation of diploid, tetraploid, octaploid and hexadecaploid nuclei from mouse liver. 4. Rat liver nuclei are isopycnic with sucrose solutions of density 1·35 at 5°.

scholarly journals Studies on protein binding of antibiotics. IV. Effect of the binding of drug to 100,000*g supernatant fluid of rabbit liver homogenates on urinary excretion.

1982 ◽  
Vol 35 (11) ◽  
pp. 1603-1609
Author(s):  
YASUO WATANABE ◽  
RIEKO KITAYAMA ◽  
TOSHIO HAYASHI ◽  
YOSHIFUMI NAKASHIMA ◽  
MASASHI NOGUCHI ◽  
...  
Keyword(s):  
Protein Binding ◽  
Urinary Excretion ◽  
Rabbit Liver ◽  
Supernatant Fluid ◽  
Liver Homogenates

scholarly journals Increase of Cholinesterase Content in Mouse Liver Homogenates after Incubation.

1956 ◽  
Vol 10 ◽  
pp. 1243-1250 ◽  
Author(s):  
Karl Håkon Skamstad ◽  
Rolf Gmelin ◽  
S. Lindstedt ◽  
A. Norman ◽  
B. Thorell
Keyword(s):  
Mouse Liver ◽  
Liver Homogenates

scholarly journals Histone Adduction with Nicotine: A Bio-Ams Study

Radiocarbon ◽  
1997 ◽  
Vol 39 (3) ◽  
pp. 293-297 ◽  
Author(s):  
X. H. Wu ◽  
H. F. Wang ◽  
Y. F. Liu ◽  
X. Y. Lu ◽  
J. J. Wang ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Accelerator Mass Spectrometry ◽  
Human Exposure ◽  
Mouse Liver ◽  
Dose Range ◽  
The Other ◽  
Histone 3 ◽  
Protein Adduction ◽  
Dna Adduction

Based on the study of DNA adduction with nicotine, we have measured the mouse hepatic histone adduction with 14C-labeled nicotine in vivo by bio-accelerator mass spectrometry (bio-AMS). In the exposure of mice to nicotine, the dose range administered was from 0.2 μg to 6.0 μg kg b.w.-1, which was equivalent to a very low level of human exposure to cigarette smoke. The adducts of either histone 1 (H1) or histone 3 (H3) with nicotine in mouse liver increased markedly with increasing nicotine dose. Our results have demonstrated that in the study of protein adduction with toxic xenobiotics as a biomarker, the AMS method achieves the highest sensitivity, 4.6 × 10-17 mol (46 amol) adducts per mg H1 protein, compared to all the other methods used previously.

scholarly journals Characterization of mouse liver α-l-fucosidase. Demonstration of unusual basic isoelectric forms of the enzyme that appear to be developmentally regulated

1985 ◽  
Vol 230 (1) ◽  
pp. 75-82 ◽  
Author(s):  
L D Laury-Kleintop ◽  
I Damjanov ◽  
J A Alhadeff
Keyword(s):  
Postnatal Development ◽  
Liver Enzyme ◽  
Human Liver ◽  
Mouse Liver ◽  
Kinetic Studies ◽  
Total Activity ◽  
Cross Reactivity ◽  
Ph Optimum ◽  
Neuraminidase Treatment ◽  
Mouse Tissues

Mouse tissues contain unusual basic isoelectric forms of α-L-fucosidase (with approximate isoelectric points of 8.3 and 9.0) in addition to the usual acidic and neutral forms previously described in tissues of other species. These unusual forms are very prominent in placenta and foetal tissues and comprise approx, 50-80% of total activity up to 11 days of postnatal development. By 15 days of postnatal development, the basic forms are diminished in amount and comprise not more than 25% of total activity. Neuraminidase treatment of adult mouse liver α-L-fucosidase led to significantly decreased amounts of acidic forms and increased amounts of the basic forms, suggesting that these forms are chemically related at least in part by sialic acid residues. Comparative kinetic studies on mouse liver, human liver and mouse placental α-L-fucosidases indicated that they have the same Km (0.05-0.06 mM) for 4-methylumbelliferyl α-L-fucopyranoside but different pH optima and thermostability properties. Mouse liver α-L-fucosidase has one pH optimum (5.5) and an acidic shoulder (centred around pH 4.0) compared with two distinct optima (4.3 and 6.8) for the human liver enzyme. Mouse placental α-L-fucosidase has a pH-activity curve comparable with that of the mouse liver enzyme except that the acidic shoulder is absent. Mouse liver α-L-fucosidase is considerably more thermolabile after preincubation at 50 degrees C than are the human liver and mouse placental enzymes, which gave similar thermodenaturation curves. Immunochemical studies indicated that mouse and human α-L-fucosidases are dissimilar antigenically but exhibit some cross-reactivity. The IgG fraction of antibody prepared in goat against human liver α-L-fucosidase was ineffective by itself in immunoprecipitating mouse liver α-L-fucosidase, but 63% and 72% of the mouse liver and placental enzymes respectively could be immunoprecipitated in the double-antibody experiments under conditions that immunoprecipitated 92% of the human liver enzyme.

scholarly journals Separation of oestrone UDP-glucuronyltransferase and p-nitrophenol UDP-glucuronyltransferase activities

1978 ◽  
Vol 171 (3) ◽  
pp. 659-663 ◽  
Author(s):  
R H Tukey ◽  
R E Billings ◽  
T R Tephly
Keyword(s):  
Deae Cellulose ◽  
The Other ◽  
Rabbit Liver ◽  
Transferase Activity ◽  
Deae Cellulose Column ◽  
Cellulose Column

Rabbit liver UDP-glucuronyltransferase activity was resolved into two separate fractions on DEAE-cellulose, one containing most of the transferase activity toward oestrone and the other most of the activity toward p-nitrophenol. These two activities were completely separated by rechromatography of each fraction on a second DEAE-cellulose column.

LINGCOD MUSCLE PHOSPHOMONOESTERASES: I. ACID PHOSPHATASES THAT HYDROLYZEp-NITROPHENYL PHOSPHATE

1960 ◽  
Vol 38 (1) ◽  
pp. 605-612 ◽  
Author(s):  
Neil Tomlinson ◽  
R. A. J. Warren
Keyword(s):  
Metal Ions ◽  
The Other ◽  
Acid Phosphatases ◽  
Free Base ◽  
Ph Optimum ◽  
Ophiodon Elongatus ◽  
Nitrophenyl Phosphate ◽  
Diethylaminoethyl Cellulose ◽  
Ph Range ◽  
Acid Phosphomonoesterase

Five fractions (A to E), each possessing acid phosphomonoesterase activity, were separated from an aqueous extract of the muscle of lingcod (Ophiodon elongatus) by stepwise chromatography on diethylaminoethyl cellulose in the free-base form.Fraction A required Zn++or Mn++for activity, was inhibited by heparin, and had its pH optimum at 6.0. Fraction E required Zn++for activity, was not inhibited by heparin, and had its pH optimum at 5.5. Fractions B, C, and D did not require metal ions for activity, and were distinguished from each other by differences in response to pH, cysteine, ethylenediaminetetraacetate, fluoride, and tartrate.The pH range over which fraction A was active was shifted to slightly higher values when Mn++was the activator rather than Zn++. Also, A was inhibited strongly by cysteine when activated by Zn++, but not when activated by Mn++. Data are presented that indicate these differences were due to different properties of the activating ions, rather than to the presence in fraction A of two enzymes, one activated by Zn++and the other by Mn++.

Sign in / Sign up

Export Citation Format

Share Document