Biochem Mol Biol Int
· 1999 Mar · PMID 10204074
·
Publisher ↗
Anion transport activity and thermotropic behavior of Band 3 are found to be altered after binding of concanavalin (Con A) to human erythrocyte ghosts and isolated Band 3. At lower Con A concentration, the rate coefficie...Anion transport activity and thermotropic behavior of Band 3 are found to be altered after binding of concanavalin (Con A) to human erythrocyte ghosts and isolated Band 3. At lower Con A concentration, the rate coefficients of anion transport enhance with increasing Con A concentration, while noticeable changes of the largest calorimetric endotherm of human erythrocyte membranes termed the C transition (Band 3) can not be observed. With 50 micrograms/ml of Con A, the rate coefficient of Con A-modified ghosts increases 34.4% in comparison with that of normal ghosts. Binding of Con A in lower concentration to ghosts bring about increase of fluidity of lipid which maybe contribute to increase anion transport via Band 3. At higher Con A concentration, the C transition tend to lower temperature with increase in Con A concentration, the C transition is shifted from 69.25 degrees C to 66.25 degrees C with 2.5 mg/ml Con A. It is suggested that the Con A-modified Band 3 possess a looser structure than normal one.
Lee YT, Kim DH, Suh JY
… +4 more, Chung JH, Lee BL, Lee Y, Choi BS
Biochem Mol Biol Int
· 1999 Mar · PMID 10204073
·
Publisher ↗
Tenecin 3, an antifungal protein, previously isolated from the insect Tenebrio molitor, inhibits growth of the fungus Candida albicans. However, the antifungal mechanism and functions of tenecin 3 remain unknown. As an i...Tenecin 3, an antifungal protein, previously isolated from the insect Tenebrio molitor, inhibits growth of the fungus Candida albicans. However, the antifungal mechanism and functions of tenecin 3 remain unknown. As an initial step to study the mechanism and functions, physical and structural properties of tenecin 3 were examined by circular dichroism (CD) analysis and 2D nuclear overhauser effect spectroscopy. These analyses suggest that tenecin 3 has a propensity of random structure with very loose turn-like elements. The CD results also indicate that this random structural propensity is not significantly affected by temperature, pH, and by the presence of organic solvents or sodium dodecyl sulfate (SDS) micelles. However, the hydrodynamic studies suggest that tenecin 3 is not in extended form in spite of its random structural feature.
Syed FB, Joshi BN, SivaRaman H
… +2 more, Khire JM, Khan MI
Biochem Mol Biol Int
· 1999 Mar · PMID 10204072
·
Publisher ↗
A lectin was isolated from Agrobacterium radiobacter cell surface and purified. It is a monomer of 40 kDa as shown by SDS-PAGE. The lectin has a pI of 9.15 and amino acid composition of the lectin shows that 44% of the a...A lectin was isolated from Agrobacterium radiobacter cell surface and purified. It is a monomer of 40 kDa as shown by SDS-PAGE. The lectin has a pI of 9.15 and amino acid composition of the lectin shows that 44% of the amino acids are hydrophobic. The lectin agglutinates rabbit erythrocytes but does not agglutinate human erythrocytes. It does not show specificity for monosaccharides except for D-glucosamine. Fetuin and its N-linked glycopeptide also inhibit the activity of the lectin but greater inhibition is shown by locust bean gum and Nicotiana tobaccum (tobacco) tissue extracts.
Biochem Mol Biol Int
· 1999 Mar · PMID 10204071
·
Publisher ↗
Aspartate kinase (AK) activity is regulated by light. The activity was more in light exposed barley seedlings than those grown in the dark. The light effect was manifested even with small exposures of 5 min duration and...Aspartate kinase (AK) activity is regulated by light. The activity was more in light exposed barley seedlings than those grown in the dark. The light effect was manifested even with small exposures of 5 min duration and red light was more effective than white light in this respect. The effect of 5 min red light could be reversed by a 5 min pulse of far-red light indicating the involvement of phytochrome in this response. The phytochrome is also involved in long term light effects (24 hr exposures with white light). Ca++ takes part in the signal transduction pathway for this light response. Western blot analysis using antibodies raised against the purified lysine- and threonine-sensitive AK isoenzymes from spinach leaves showed no cross reaction with the antibodies to the threonine-sensitive AK in the dark and 5 min far-red light exposed seedlings. But the protein band was detected in the white and red lights. Northern blot analysis of seedlings grown under dark and exposed to white, red and far-red lights and probed with the gene encoding aspartokinase-homoserine dehydrogenase (AKHSD) protein indicated that the gene was differentially expressed. In dark grown seedlings, AKHSD transcript was in low concentration as compared to white light where the transcript concentration was high. A 5 min red light pulse increased the transcript concentration significantly in contrast to 5 min far-red light. The transcript concentration was reduced when 5 min red light was followed by a 5 min far-red light pulse. The AK activity in dark-raised seedlings is attributed to the presence of only one isoenzyme that is sensitive to lysine but insensitive to Ca++ and calmodulin (CAM). In both white and red light exposed seedlings, three isoenzymes of AK were detected. Two of these were sensitive to threonine while one was sensitive to lysine. Both of the threonine sensitive isoenzymes were activated by Ca++ and CAM. Also one of these isoenzymes seems to be located and synthesized in chloroplasts because its synthesis was completely inhibited by chloramphenicol but not by cycloheximide.
Nagi MN, Alam K, Badary OA
… +3 more, al-Shabanah OA, al-Sawaf HA, al-Bekairi AM
Biochem Mol Biol Int
· 1999 Jan · PMID 10092955
·
Publisher ↗
Thymoquinone (TQ) is the major active component of the volatile oil of Nigella sativa seeds. The effects of TQ on carbon tetrachloride (CCl4)-induced hepatotoxicity was investigated in male Swiss albino mice. Carbon tetr...Thymoquinone (TQ) is the major active component of the volatile oil of Nigella sativa seeds. The effects of TQ on carbon tetrachloride (CCl4)-induced hepatotoxicity was investigated in male Swiss albino mice. Carbon tetrachloride (20 microliters/Kg, i.p.) injected into mice, induced damage to liver cells and was followed by the increase in serum alanine aminotransferase (ALT) activity after 24 h. Oral administration of TQ in a single dose (100 mg/Kg) resulted in significant (p < 0.001) protection against the hepatotoxic effects of CCl4. TQ was tested as a substrate for mice hepatic DT-diaphorase in the presence of NADH. TQ appears to undergo reduction to dihydrothymoquinone (DHTQ). Reduction rates as a function of protein (liver homogenate) and substrate (TQ) concentrations are reported. An apparent K(m) of 0.1 mM and an apparent Vmax of 74 mumol/min/g liver were measured. TQ and DHTQ inhibited the in vitro non-enzymatic lipid peroxidation in liver homogenate (induced by Fe(3+)-ascorbate) in a dose dependent manner. In this in vitro model DHTQ was more potent in comparison with TQ and butylated hydroxytoluene (BHT). The IC50 for DHTQ, TQ and BHT were found to be 0.34, 0.87 and 0.58 microM respectively. The data suggest that the in vivo protective action of TQ against CCl4-induced hepatotoxicity may be mediated through the combined antioxidant properties of TQ and its metabolite DHTQ.
Biochem Mol Biol Int
· 1999 Jan · PMID 10092954
·
Publisher ↗
To evaluate the possibility that the protooncogene c-myc plays a role in ventral prostate, the effects of castration have been investigated at a beginning of a period by Northern blot hybridization and the levels of c-my...To evaluate the possibility that the protooncogene c-myc plays a role in ventral prostate, the effects of castration have been investigated at a beginning of a period by Northern blot hybridization and the levels of c-myc mRNA were also compared with mRNA of androgen-regulated genes, C1 and TRPM-2. Levels of c-myc mRNA in ventral prostate increased with maximal stimulation reached at 6 hours (early induction) and 48 hours (late induction) after castration, respectively. The level of C1 mRNA did not change and TRPM-2 was not detected at early induction of c-myc mRNA after castration. The level of early induction of c-myc mRNA after castration was increased in ventral prostate treated with cycloheximide, but it was almost reduced by actinomycin-D pretreatment. Administration of androgen at the time of castration prevented early induction of c-myc mRNA. These results suggest that protooncogene c-myc is differentially regulated in ventral prostate after castration.
Miranda-Duarte A, Valdés-Flores M, Miranda-Zamora R
… +3 more, Díaz-Zagoya JC, Kofman-Alfaro SH, Cuevas-Covarrubias SA
Biochem Mol Biol Int
· 1999 Jan · PMID 10092953
·
Publisher ↗
The enzyme steroid sulfatase (STS) hydrolyses 3-beta-hydroxysteroid sulfates. The female-male STS activity ratio is 1.04-1.7:1 in several cell lines in adults and reaches 2:1 in prepubertal subjects. In fibroblasts, STS...The enzyme steroid sulfatase (STS) hydrolyses 3-beta-hydroxysteroid sulfates. The female-male STS activity ratio is 1.04-1.7:1 in several cell lines in adults and reaches 2:1 in prepubertal subjects. In fibroblasts, STS values in X-chromosome abnormalities show a partial positive correlation according to the number of X-chromosomes. X-linked ichthyosis (XLI) carriers, with only one copy of the STS gene, present lower STS levels than normal controls. This study analyzes the STS activity in leukocytes of 46,Xi(Xq); 45,X; XLI carriers and normal controls using 7-[3H]-dehydroepiandrosterone sulfate as substrate. X-monosomy (1.07 +/- 0.18 pmol/mg protein/h), Xq isochromosome (1.02 +/- 0.12 pmol/mg protein/h) and normal females (1.03 +/- 0.11 pmol/mg protein/h) had similar STS values (p > 0.05). XLI-carriers and males showed the lowest STS levels (0.34 +/- 0.04 pmol/mg protein/h, p < 0.001 and 0.82 +/- 0.14 pmol/mg protein/h, p < 0.05, respectively). Female-male STS activity ratio in leukocytes was 1.3:1. These data indicate that a complex mechanism regulates the STS expression depending on each type of cell line.
Raugei G, Degl'Innocenti D, Chiarugi P
… +3 more, Solito E, Modesti A, Ramponi G
Biochem Mol Biol Int
· 1999 Jan · PMID 10092952
·
Publisher ↗
In a previous paper we observed a direct involvement of acylphosphatase in differentiation, associated with enhanced levels of the enzyme in the cell. We have here investigated the subcellular localization of the two kno...In a previous paper we observed a direct involvement of acylphosphatase in differentiation, associated with enhanced levels of the enzyme in the cell. We have here investigated the subcellular localization of the two known acylphosphatase isoforms during this process. We show that in C2C12 myoblast cells, muscle type acylphosphatase accumulates in the nucleus during differentiation. The same pattern of accumulation is observed also in K562 erythroleukemia cells, although at a lower extent: this fact indicates that this phenomenon is not restricted to muscular cells but rather it could be of general importance in the differentiative process. The common type acylphosphatase, showing an 8-fold increase in the cytoplasm during differentiation, does not accumulate in the nucleus, suggesting distinct roles of the two isoenzymes in this process.
Biochem Mol Biol Int
· 1999 Jan · PMID 10092951
·
Publisher ↗
The widely accepted model of reaction center /RC/ functioning is proved to come into contradiction with some recent data. In particular, it cannot explain why only a minor part of electronic excitations (approximately 10...The widely accepted model of reaction center /RC/ functioning is proved to come into contradiction with some recent data. In particular, it cannot explain why only a minor part of electronic excitations (approximately 10%) escapes from excited RC special pairs back to antenna BChls. Therefore we believe that the model must be substantially modernized. In 1981 we developed a new model/1,2/. We suggested a femtosecond state to precede primary e-transfer reaction due to reorientation of water molecule dipole in the electric field of excited RC dimer. This mechanism is responsible for energy trapping before the primary e-transport occurs. During last years his mechanism got support from various experimental works. Now this polarization model claims to fit all reliable experimental data at least in bacterial photosynthesis.
Bramucci M, Miano A, Quassinti L
… +3 more, Maccari E, Murri O, Amici D
Biochem Mol Biol Int
· 1999 Jan · PMID 10092950
·
Publisher ↗
This study was conducted to determine the presence of the angiotensin converting enzyme in commercial sera used in cell culture medium. The aim of the research was to bring the presence of proteinases (angiotensin conver...This study was conducted to determine the presence of the angiotensin converting enzyme in commercial sera used in cell culture medium. The aim of the research was to bring the presence of proteinases (angiotensin converting enzyme) to cell culture users' knowledge and to give some data for solving problems about the development of peptides as useful drugs. The enzymes, purified from foetal bovine, adult bovine, foetal equine, adult equine, and human sera, showed molecular weights of about 170 kDa. Captopril and lisinopril inhibited enzyme activities at nanomolar concentrations. The enzymes were able to hydrolyze, with different efficiency, angiotensin I, bradykinin and epidermal mitosis inhibiting pentapeptide. The heat inactivation of commercial sera at 56 degrees C for 30 min showed a reduction of ACE activity of about 35-80%. Therefore, the presence of ACE activity in commercial sera can influence the activity of biological peptides tested on cell lines cultured "in vitro."
Biochem Mol Biol Int
· 1999 Jan · PMID 10092949
·
Publisher ↗
Doxyl stearate spin probes which differed in the attachment of the nitroxide free radical to the fatty acid have been used to study membrane fluidity in ozone-treated bovine erythrocytes and liposomes. Analysis of EPR sp...Doxyl stearate spin probes which differed in the attachment of the nitroxide free radical to the fatty acid have been used to study membrane fluidity in ozone-treated bovine erythrocytes and liposomes. Analysis of EPR spectra of spin labels incorporated into lipid bilayer of the erythrocyte membranes indicates an increase in the mobility and decrease in the order of membrane lipids. In isolated erythrocyte membranes (ghosts) the most significant changes were observed for 16-doxylstearic acid. In intact erythrocytes statistically significant were differences for 5-doxylstearic acid. The effect of ozone on liposomes prepared from a lipid extract of erythrocyte lipids was marked in the membrane microenvironment sampled by all spin probes. Ozone apparently leads to alterations of membrane dynamics and structure but does not cause increased rigidity of the membrane.
Akahori A, Gabryelak T, Jóźwiak Z
… +1 more, Gondko R
Biochem Mol Biol Int
· 1999 Jan · PMID 10092948
·
Publisher ↗
Fish erythrocytes were used to elucidate the effect of zinc ions on the cell antioxidant defence system. It was detected that an increase of the Zn2+ concentration (0.01-1 mM) leads to a marked decrease (p < 0.05) in the...Fish erythrocytes were used to elucidate the effect of zinc ions on the cell antioxidant defence system. It was detected that an increase of the Zn2+ concentration (0.01-1 mM) leads to a marked decrease (p < 0.05) in the catalase and the glutathione peroxidase activities. We observed a loss of 14-39% activity of glutathione peroxidase, and 16-20% diminution for catalase. No significant changes were found in case of the superoxide dismutase. Incubation of red blood cells with zinc brought about a decrease of the erythrocyte thiol group content. Treatment of carp erythrocytes with zinc ions also resulted in enhanced hemolysis and in the induction of significant (p < 0.001) changes in the intracellular glucose level. The increase of glucose concentration in the erythrocytes was correlated with increased concentration of metal in the incubation medium. It was proposed that Zn could affect transport systems across the red blood cells and therefore increased the permeability of the membranes to small molecules (e.g. hexose), and led to hemolysis. Zinc ions could act as a potential cell toxicant, leading to disturbances in functions of the antioxidant defence system and to alterations in the erythrocyte membrane properties.
Biochem Mol Biol Int
· 1999 Jan · PMID 10092947
·
Publisher ↗
The effect of 11 sulfosuccinic acid ester surfactants on the abiotrophic developmental forms of the asexual spores of Plasmopara halstedii was determined. The strength and the selectivity of the effect was separated by t...The effect of 11 sulfosuccinic acid ester surfactants on the abiotrophic developmental forms of the asexual spores of Plasmopara halstedii was determined. The strength and the selectivity of the effect was separated by the spectral mapping technique and the relationship between the biological activities and physico-chemical parameters of anionic surfactants was elucidated by stepwise regression analysis. It was established that the plasmalemma of cell wall less zoospores showed the highest and the resting zoosporangia the lowest average sensitivity toward the surfactants. The biological efficacy of surfactants was highly different the di-n-octyl ester being the most effective. Calculations proved that both the strength and selectivity of the biological activity mainly depends on the lipophilicity of the molecule and, to a lesser extent, on the electronic parameters.
Srikanth V, Aruldhas MM, Srinivasan N
… +2 more, Govindarajulu P, Balasubramanian K
Biochem Mol Biol Int
· 1999 Jan · PMID 10092946
·
Publisher ↗
Chronic alcohol abuse is often associated with reproductive disorders. Sperm monosaccharides play an indispensable role in sperm-egg interactions and fertilization. Ethanol (3 g/kg body weight as 25%, v/v) was given by g...Chronic alcohol abuse is often associated with reproductive disorders. Sperm monosaccharides play an indispensable role in sperm-egg interactions and fertilization. Ethanol (3 g/kg body weight as 25%, v/v) was given by gastric intubation twice daily for 30 days while in another group, rats which had been treated with ethanol were withdrawn from treatment for a further period of 30 days, in order to assess the reversibility of the ethanol-induced effects. Epididymal ethanol content, sperm monosaccharides and the fertility of ethanol treated and ethanol withdrawn rats were assessed. Ethanol ingestion caused a significant decrease in sperm monosaccharides suggesting defective glycosylation of sperm surface proteins. Sperm monosaccharides and fertility were returned to normal following the withdrawal of ethanol. Ethanol-induced changes in sperm monosaccharides may be one of the reasons for the reduced fertility of ethanol treated rats.
Biochem Mol Biol Int
· 1999 Jan · PMID 10092945
·
Publisher ↗
There is a notable discrepancy between the FAS (fatty acid synthase) activity of four types of fowl (egg chicken, meat chicken, egg duck, and meat duck) with distinctively different body fat levels. There is a 14.8 fold...There is a notable discrepancy between the FAS (fatty acid synthase) activity of four types of fowl (egg chicken, meat chicken, egg duck, and meat duck) with distinctively different body fat levels. There is a 14.8 fold difference per unit body weight between the maximum and minimum FAS activities. The three major factors affecting this discrepancy are liver weight per unit body weight, which is 2.3 times greater in meat ducks than in egg chickens, the amount of FAS protein per gram of liver, which is 1.85 times greater in meat ducks than in egg chickens, and the FAS specific activity in meat ducks, which is 3.5 times greater in meat ducks than in egg chickens. Within the same species of egg chickens, the abdomen fat per kg of body weight at 470 days after egg production is 66 times greater than 90 days before egg production and the liver FAS activity is increased 9.6 fold. The 9.6 fold FAS activity increase resulted from an increase in the specific activity, since the liver weight per kilogram of body weight remained constant at approx. 20 grams and the FAS weight per gram of liver also remained constant at approx. 4.5 mg. This shows that the control of the basic FAS activity level which is closely related to the level of body fat does not mainly arise from genetic control. For the same kind of fowl, the control of the basic FAS activity level occurs after gene expression. It is suggested that control may be imposed in the folding phase when new peptides give rise to functional proteins.
Zajoncová L, Frébort I, Luhová L
… +3 more, Sebela M, Galuszka P, Pec P
Biochem Mol Biol Int
· 1999 Jan · PMID 10092944
·
Publisher ↗
Kinetic properties of novel amine oxidase isolated from sainfoin (Onobrychis viciifolia) were compared to those of typical plant amine oxidase (EC 1.4.3.6) from lentil (Lens culinaris). The amine oxidase from sainfoin wa...Kinetic properties of novel amine oxidase isolated from sainfoin (Onobrychis viciifolia) were compared to those of typical plant amine oxidase (EC 1.4.3.6) from lentil (Lens culinaris). The amine oxidase from sainfoin was active toward substrates, such as 1,5-diaminopentane (cadaverine) with K(m) of 0.09 mM and 1,4-diaminobutane (putrescine) with K(m) of 0.24 mM. The maximum rate of oxidation for cadaverine at saturating concentration was 2.7 fold higher than that of putrescine. The amine oxidase from lentil had the maximum rate for putrescine comparable to the rate of sainfoin amine oxidase with the same substrate. Both amine oxidases, like other plant Cu-amine oxidases, were inhibited by substrate analogs (1,5-diamino-3-pentanone, 1,4-diamino-2-butanone and aminoguanidine), Cu2+ chelating agents (diethyltriamine, 1,10-phenanthroline, 8-hydroxyquinoline, 2,2'-bipyridyl, imidazole, sodium cyanide and sodium azide), some alkaloids (L-lobeline and cinchonine), some lathyrogens (beta-aminopropionitrile and aminoacetonitrile) and other inhibitors (benzamide oxime, acetone oxime, hydroxylamine and pargyline). Tested by Ouchterlony's double diffusion in agarose gel, polyclonal antibodies against the amine oxidase from sainfoin, pea and grass pea cross-reacted with amine oxidases from several other Fabaceae and from barley (Hordeum vulgare) of Poaceae, while amine oxidase from the filamentous fungus Aspergillus niger did not cross-react at all. However, using Western blotting after SDS-PAGE with rabbit polyclonal antibodies against the amine oxidase from Aspergillus niger, some degree of similarity of plant amine oxidases from sainfoin, pea, field pea, grass pea, fenugreek, common melilot, white sweetclover and Vicia panonica with the A. niger amine oxidase was confirmed.
Lee Y, Hong M, Kim YJ
… +6 more, Kim JW, Kim CH, Lee KS, Chang SY, Lim JS, Choe IS
Biochem Mol Biol Int
· 1999 Jan · PMID 10092943
·
Publisher ↗
A chromosomal DNA sequence harboring a processed AK2B pseudogene was isolated from a human genomic library. It was a variant of the AK2B gene sequence including several point mutations, deletions, and insertions. The nuc...A chromosomal DNA sequence harboring a processed AK2B pseudogene was isolated from a human genomic library. It was a variant of the AK2B gene sequence including several point mutations, deletions, and insertions. The nucleotide sequence of the ORF of the AK2B pseudogene predicted a truncated form of the AK2B mutant suggesting that the processed pseudogene is nonfunctional. A repetitive sequence, AAAAGAGAG, found in the 5' and 3' flanking regions of the pseudogene and the poly(A) tract in the 3' end junction suggest that a mRNA of AK2B may have been converted to the processed pseudogene by retrotransposition events. Previously, it was suggested that an adenylate kinase (AK) 2 related gene on chromosome 2, confirmed by Southern analysis using somatic cell hybrid cell lines, may be a processed pseudogene. It is proposed that the processed pseudogene isolated in this study may be the AK2 related nonfunctional gene localized on human chromosomes 2.
Bessiere P, Bancel F, Cottin P
… +1 more, Ducastaing A
Biochem Mol Biol Int
· 1999 Jan · PMID 10092942
·
Publisher ↗
The effects of pressure on mu and m-calpain stability and specific activity have been examined. Activity and stability of these neutral calcium-dependent heterodimeric proteinases were studied using an in-house built bio...The effects of pressure on mu and m-calpain stability and specific activity have been examined. Activity and stability of these neutral calcium-dependent heterodimeric proteinases were studied using an in-house built bioreactor allowing on-line spectrophotometric monitoring with retention of pressure. Both isozymes were founded to be rather baro-sensitive with t1/2 at 1500 bar of 6 min and 11 min for mu and m-calpain respectively. Activity measurements under pressure showed a biphasic behavior for both proteinases with a slight activation for pressure up to 500 bar and 750 bar for m and mu-calpain respectively. Activation volume changes indicated that the proteolytic reaction was alternatively favored and disfavored by pressure due to catalytic step activation associated with enzyme-substrate binding step being continuously inhibited by pressure. Furthermore, autoproteolysis of calpain, a calcium dependent phenomenon was inhibited by application of pressure indicating that pressure inhibition of proteolytic activity could also be due to Ca2(+)-binding decrease under pressure. Implication of these results with catalytic mechanism of these heterodimeric proteinases is also discussed.
Harvey KA, Siddiqui RA, Reeves M
… +4 more, Kovala T, Dugan M, Akard LP, English D
Biochem Mol Biol Int
· 1999 Jan · PMID 10092941
·
Publisher ↗
Phosphatidic acid and its hydrolysis product, diacylglycerol, play potentially vital roles as extracellular messengers in numerous cellular systems and may play a key role in regulating hematopoiesis. In this study, we d...Phosphatidic acid and its hydrolysis product, diacylglycerol, play potentially vital roles as extracellular messengers in numerous cellular systems and may play a key role in regulating hematopoiesis. In this study, we describe an ecto-phosphatidic acid phosphohydrolase that potentially regulates cellular responses to phosphatidic acid on bone marrow derived human hematopoietic progenitors. We partially purified hematopoietic progenitor ecto-PAPase using a novel in-gel phosphatase assay and then characterized the enzyme on phenotypically defined subpopulations of hematopoietic CD34+ progenitors isolated by flow cytometry. The most pronounced PAPase activity was confined to uncommitted CD34+/CD38+ hematopoietic progenitors, which lacked the expression of other lineage-associated antigens. We conclude that hematopoietic progenitor cells at various stages of maturation possess a potent ecto-PAPase, an enzyme well positioned to regulate progenitor cell growth and differentiation induced by phosphatidic acid and related lipids.
Biochem Mol Biol Int
· 1999 Jan · PMID 10092940
·
Publisher ↗
In the present work, we have determined the steady-state kinetic constants for yeast alcohol dehydrogenase-catalyzed oxidation of allyl alcohol (H2C = CH.CH2OH) and ethylene glycol (HOCH2.CH2OH) with NAD+, at pH 8.0; als...In the present work, we have determined the steady-state kinetic constants for yeast alcohol dehydrogenase-catalyzed oxidation of allyl alcohol (H2C = CH.CH2OH) and ethylene glycol (HOCH2.CH2OH) with NAD+, at pH 8.0; also, a kinetic mechanism for the former reaction was determined at the same pH. In addition, it was found that acrolein is a potent inhibitor of yeast alcohol dehydrogenase.