scholarly journals The removal of cytosolic-type aldehyde dehydrogenase from preparations of sheep liver mitochondrial aldehyde dehydrogenase and the unusual properties of the purified mitochondrial enzyme in assays

1984 ◽  
Vol 224 (1) ◽  
pp. 163-169
Author(s):  
S Allanson ◽  
F M Dickinson
Keyword(s):  
Aldehyde Dehydrogenase ◽  
The Other ◽  
Ph Gradient ◽  
Mitochondrial Enzyme ◽  
Sheep Liver ◽  
Species Being ◽  
Gradient Chromatography ◽  
Lag Phases

The pI approximately 5.2 isoenzymes of mitochondrial aldehyde dehydrogenase were separated from the other isoenzymes by pH-gradient chromatography on DEAE-Sephacel. The pI approximately 5.2 material is immunologically identical with cytosolic aldehyde dehydrogenase. It also shows sensitivity to 20 microM-disulfiram and insensitivity to 4M-urea in assays. These and other criteria seem to establish that the material is identical with the cytosolic enzyme. Mitochondrial enzyme that had been purified to remove pI approximately 5.2 isoenzymes shows concentration-dependent lag phases in assays. These effects are possibly due to the slow establishment of equilibrium between tetramer and either dimers or monomers, with the dissociated species being intrinsically more active than the tetramer.

scholarly journals Reaction between sheep liver mitochondrial aldehyde dehydrogenase and various thiol-modifying reagents

1989 ◽  
Vol 261 (1) ◽  
pp. 281-284 ◽  
Author(s):  
K M Loomes ◽  
T M Kitson
Keyword(s):  
Aldehyde Dehydrogenase ◽  
Related Compound ◽  
Physiological Responses ◽  
Enzymic Activity ◽  
Cysteine Residues ◽  
Mitochondrial Enzyme ◽  
Step Process ◽  
Cytoplasmic Enzyme ◽  
Sheep Liver

Sheep liver mitochondrial aldehyde dehydrogenase reacts with 2,2′-dithiodipyridine and 4,4′-dithiodipyridine in a two-step process: an initial rapid labelling reaction is followed by slow displacement of the thiopyridone moiety. With the 4,4′-isomer the first step results in an activated form of the enzyme, which then loses activity simultaneously with loss of the label (as has been shown to occur with the cytoplasmic enzyme). With 2,2′-dithiodipyridine, however, neither of the two steps of the reaction has any effect on the enzymic activity, showing that the mitochondrial enzyme possesses two cysteine residues that must be more accessible or reactive (to this reagent at least) than the postulated catalytically essential residue. The symmetrical reagent 5,5′-dithiobis-(1-methyltetrazole) activates mitochondrial aldehyde dehydrogenase approximately 4-fold, whereas the smaller related compound methyl l-methyltetrazol-5-yl disulphide is a potent inactivator. These results support the involvement of mixed methyl disulphides in causing unpleasant physiological responses to ethanol after the ingestion of certain antibiotics.

scholarly journals The use of pH-gradient ion-exchange chromatography to separate sheep liver cytoplasmic aldehyde dehydrogenase from mitochondrial enzyme contamination, and observations on the interaction between the pure cytoplasmic enzyme and disulfiram

1981 ◽  
Vol 199 (3) ◽  
pp. 573-579 ◽  
Author(s):  
F M Dickinson ◽  
G J Hart ◽  
T M Kitson
Keyword(s):  
Ion Exchange ◽  
Aldehyde Dehydrogenase ◽  
Active Sites ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Ph Gradient ◽  
Original Activity ◽  
Covalent Interaction ◽  
Cytoplasmic Enzyme ◽  
Sheep Liver

1. Sheep liver cytoplasmic aldehyde dehydrogenase can be purified from contamination with the mitochondrial form of the enzyme by pH-gradient ion-exchange chromatography. The method is simple, reproducible and efficient. 2. The purified cytoplasmic enzyme retains about 2% of its original activity in the presence of a large excess of disulfiram. This suggests that the disulfiram-reactive thiol groups are not essential for covalent interaction with the aldehyde substrate during catalysis, as has sometimes been suggested. 3. Between 1.5 and 2.0 molecules of disulfiram per tetrameric enzyme molecule account for the observed loss of activity, suggesting that the enzyme may have only two functional active sites. 4. Experiments show that disulfiram-modified enzyme retains the ability to bind NAD+ and NADH.

scholarly journals The separation of sheep liver cytoplasmic and mitochondrial aldehyde dehydrogenases by isoelectric focusing, and observations on the purity of preparations of the cytoplasmic enzyme, and their sensitivity towards inhibition by disulfiram

1979 ◽  
Vol 179 (3) ◽  
pp. 709-712 ◽  
Author(s):  
F M Dickinson ◽  
S Berrieman
Keyword(s):  
Isoelectric Focusing ◽  
Aldehyde Dehydrogenase ◽  
Liver Enzymes ◽  
Mitochondrial Enzyme ◽  
Selective Precipitation ◽  
Aldehyde Dehydrogenases ◽  
Cytoplasmic Enzyme ◽  
Sheep Liver ◽  
Ph Range

Preparations of sheep liver cytoplasmic aldehyde dehydrogenase obtained by published methods were found by analytical isoelectric focusing in the pH range 5–8 to contain 5–10% by weight of the mitochondrial aldehyde dehydrogenase. Under the conditions used the pI of the cytoplasmic enzyme is 6.2 and that of the mitochondrial enzyme 6.6. The mitochondrial enzyme can be removed from the preparation by selective precipitation of the cytoplasmic enzyme with (NH4)2SO4. Kinetic experiments and inhibition experiments with disulfiram show that the properties of the two sheep liver enzymes are so different that the presence of 10% mitochondrial enzyme in preparations of the cytoplasmic enzyme can introduce serious errors into results. Our results suggest that the presence of 10 microM-disulfiram in assays may completely inactivate the pure cytoplasmic enzyme. This result is in contrast with a previous report [kitson (1978) Biochem. U. 175, 83–90].

scholarly journals Neomillspaughia hondurensis (Polygonaceae), a new species from Central America

Phytotaxa ◽  
2013 ◽  
Vol 144 (2) ◽  
pp. 56
Author(s):  
JUAN JAVIER ORTIZ-DÍAZ ◽  
ITZIAR ARNELAS ◽  
JUAN TUN ◽  
JOSÉ SALVADOR FLORES
Keyword(s):  
New Species ◽  
Central America ◽  
The Other ◽  
Comprehensive Comparison ◽  
Species Being ◽  
A New Species

A new species Neomillspaughia hondurensis (Polygonaceae) from Honduras is described and illustrated. This species is morphologically and ecollogicaly different from the other two currently known Neomillspaughia species, being more related to N. emarginata than to N. paniculata. A comprehensive comparison and a key for the three species are provided. Se describe e ilustra la nueva especie Neomillspaughia hondurensis (Polygonaceae) de Honduras. Esta especie es morfológicamente y ecológicamente diferente de las dos únicas especies de Neomillspaughia, estando más relacionada con N. emarginata que con N. paniculata. Se proporciona información comparativa de la nueva especie con las especies relacionadas y una clave para la identificación de las mismas.

scholarly journals Intercalibration of different light-traps and bulbs used in moth monitoring in northern Europe

1998 ◽  
Vol 9 (1) ◽  
pp. 37-51 ◽  
Author(s):  
Reima Leinonen ◽  
Guy Söderman ◽  
Juhani Itämies ◽  
Seppo Rytkönen ◽  
Ilpo Rutanen
Keyword(s):  
The Other ◽  
Northern Europe ◽  
Mercury Vapour ◽  
Light Traps ◽  
Mercury Vapour Lamp ◽  
Species Being ◽  
Tungsten Lamp

Four different combinations of light-traps and bulbs were tested during the summer 1996 in Kainuu, northern Finland: a Jalas model with a 160-W (J/160W) blended light lamp or a 125-W (J/125W) mercury vapour lamp, a Ryrholm trap with a 125-W (R/125W) mercury vapour lamp and a Rothamsted trap with a 200-W tungsten lamp (G/200W). The traps were rotated between four sites every night, but were kept in the same position for the fifth night in order to prevent the possible influence of moonlight. The longest distance between the traps was 150m, and there was no direct visibility between any of them. Three orders were inspected, i.e. Lepidoptera, Coleoptera and Hemiptera, the total numbers of individuals and species being as follows: 20857/425, 862/101 and 1868/58. G/200W collected significantly fewer moths than the other traps. In some cases, J/125W collected significantly more moths and less species than the J/160W design. The R/125W design collected significantly more species than the J/160W design. Similar differences in the effectiveness of the lamps and traps were found in the case of Coleoptera and Hemiptera. Alpha diversities showed the same trend.

scholarly journals A MARXIST READING OF LITTLE FIRES EVERYWHERE (2017) BY CELESTE NG

2020 ◽  
Vol 9 (3) ◽  
Author(s):  
Dwi Mayang Sagita ◽  
Delvi Wahyuni
Keyword(s):  
Literary Theory ◽  
Human Body ◽  
Karl Marx ◽  
The Other ◽  
The Novel ◽  
Surrogate Mother ◽  
Female Protagonists ◽  
Species Being

This thesis is an analysis of a novel written by Celeste Ng entitled Little Fires Everywhere (2017). This analysis looks at the commodification and alienation that is experienced by women who involved in surrogacy and adoption. This analysis employes Marxist literary theory to explain the phenomena in the novel. The analysis focuses on two issues of commodification and alienation that are proposed by Karl Marx as seen through two female protagonists which are Mia Warren and Bebe Chow. This analysis also depends a lot on the narrator to determine which parts of the novel are used as the data. The result of the study shows that Mia Warren experienced commodification of the human body and four kinds of alienation such as alienation from the product of labor, alienation from the act of production, alienation from the species being, and alienation from other people bacause she becomes a surrogate mother. The other protagonist, Bebe Chow, also experienced four kinds of alienation because her child is adopted.

scholarly journals GENOME SIZE IN THREE SPECIES OF Glandularia AND THEIR HYBRIDS

2019 ◽  
Vol 30 (2) ◽  
pp. 47-54
Author(s):  
M.R. Ferrari ◽  
E.J. Greizerstein ◽  
L. Poggio
Keyword(s):  
Genome Size ◽  
Dna Content ◽  
High Frequency ◽  
Parental Species ◽  
The Other ◽  
F1 Hybrids ◽  
Homoeologous Pairing ◽  
The Relationship ◽  
Species Being ◽  
Homoeologous Chromosomes

In this work the relationship between genome size of Glandularia species and the meiotic configurations found in their hybrids are discussed. Glandularia incisa (Hook.) Tronc., growing in two localities of Corrientes and Córdoba provinces, Argentina, with different ecological conditions, showed inter-population variability of the 2C-value. The DNA content found in the Corrientes locality (2.41 pg) was higher than that obtained in the Córdoba locality (2.09 pg) which has more stressful environmental conditions than the former. These values are statistically different from those that were found in Glandularia pulchella (Sweet) Tronc. from Corrientes (1.43 pg) and in Glandularia perakii Cov. et Schn from Córdoba (1.47 pg). The DNA content of the diploid F1 hybrids, G. pulchella × G. incisa and G. perakii × G. incisa, differed statistically from the DNA content of the parental species, being intermediate between them. Differences in the frequency of pairing of homoeologous chromosomes were observed in the hybrids; these differences cannot be explained by differences in genome size since hybrids with similar DNA content differ significantly in their meiotic behavior. On the other hand, the differences in the DNA content between the parental species justify the presence of a high frequency of heteromorphic open and closed bivalents and univalents with different size in the hybrids. Key words: Intra-specific DNA content variability, homoeologous pairing, heteromorphic bivalents

scholarly journals Studies on the mechanism of sheep liver cytosolic aldehyde dehydrogenase

1985 ◽  
Vol 225 (1) ◽  
pp. 159-165 ◽  
Author(s):  
F M Dickinson
Keyword(s):  
Aldehyde Dehydrogenase ◽  
Kinetic Studies ◽  
Dissociation Reaction ◽  
Quenching Effect ◽  
Sheep Liver ◽  
Association Reaction ◽  
Hydrolysis Of

The dissociation of the aldehyde dehydrogenase X NADH complex was studied by displacement with NAD+. The association reaction of enzyme and NADH was also studied. These processes are biphasic, as shown by McGibbon, Buckley & Blackwell [(1977) Biochem. J. 165, 455-462], but the details of the dissociation reaction are significantly different from those given by those authors. Spectral and kinetic experiments provide evidence for the formation of abortive complexes of the type enzyme X NADH X aldehyde. Kinetic studies at different wavelengths with transcinnamaldehyde as substrate provide evidence for the formation of an enzyme X NADH X cinnamoyl complex. Hydrolysis of the thioester relieves a severe quenching effect on the fluorescence of enzyme-bound NADH.

scholarly journals Impact of the column on effluent pH in cation exchange pH gradient chromatography, a practical study

2020 ◽  
Vol 1626 ◽  
pp. 461350 ◽  
Author(s):  
Evelin Farsang ◽  
Krisztián Horváth ◽  
Alain Beck ◽  
Qi Wang ◽  
Matthew Lauber ◽  
...  
Keyword(s):  
Cation Exchange ◽  
Ph Gradient ◽  
Gradient Chromatography

scholarly journals The effect of disulfiram on the aldehyde dehydrogenases of sheep liver

1975 ◽  
Vol 151 (2) ◽  
pp. 407-412 ◽  
Author(s):  
T M Kitson
Keyword(s):  
Ph Dependence ◽  
Maximum Velocity ◽  
Enzyme Reaction ◽  
Thiol Group ◽  
Inhibitory Effect ◽  
Mitochondrial Enzyme ◽  
Aldehyde Dehydrogenases ◽  
Sheep Liver ◽  
Rate Profile

1. The effect of disulfiram on the activity of the cytoplasmic and mitochondrial aldehyde dehydrogenases of sheep liver was studied. 2. Disulfiram causes an immediate inhibition of the enzyme reaction. The effect on the cytoplasmic enzyme is much greater than on the mitochondrial enzyme. 3. In both cases, the initial partial inhibition is followed by a gradual irreversible loss of activity. 4. The pH-rate profile of the inactivation of the mitochondrial enzyme by disulfiram and the pH-dependence of the maximum velocity of the enzyme-catalysed reaction are both consistent with the involvement of a thiol group. 5. Excess of 2-mercaptoethanol or GSH abolishes the effect of disulfiram. However, equimolar amounts of either of these reagents and disulfiram cause an effect greater than does disulfiram alone. It was shown that the mixed disulphide, Et2N-CS-SS-CH2-CH2OH, strongly inhibits aldehyde dehydrogenase. 6. The inhibitory effect of diethyldithiocarbamate in vitro is due mainly to contamination by disulfiram.

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