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1.
Distribution of polyamines and their related catabolic enzyme in etiolated and light-grown leguminosae seedlings 总被引:3,自引:0,他引:3
Diamine-oxidase (DAO; EC 1.4.3.6) activity and di-and polyamine levels were estimated along the epicotyl and root of light-grown and etiolated lentil (Lens culinaris Medicus) and pea (Pisum sativum L.) seedlings. The activity of DAO was higher in etiolated epicotyls than in lightgrown ones. In both species there was a positive correlation between DAO activity and the diamine (putrescine and cadaverine) levels along the whole epicotyl and root. Polyamine (spermine and spermidine) distribution seemed to be associated with the meristematic and elongating zone of the epicotyl and root. The physiological function of DAO is discussed in relation to its possible role in providing hydrogen peroxide to peroxidase-dependent reactions occurring in the cell wall.Abbreviations CAD
cadaverine
- DA
diamine
- DAO
diamine oxidase
- PA
polyamine
- PUT
putrescine
- SPD
spermidine
- SPM
spermine 相似文献
2.
Electron-microscopic cytochemical localization of diamine and polyamine oxidases in pea and maize tissues 总被引:1,自引:0,他引:1
An electron-microscopic cytochemical method was used to localize diamine oxidase (DAO) in pea and polyamine oxidase (PAO) in maize (Zea mays L.). The method, based on the precipitation of amine-oxidase-generated H2O2 by CeCl3, was shown to be specific for DAO and PAO and permitted their localization in plant tissues with a high degree of resolution. Both enzymes are localized exclusively in the cell wall. Both DAO- and PAO-activity staining is most intense in the middle lamellar region of the wall and in cells exhibiting highly lignified walls. The oxidases could provide H2O2 for peroxidase-mediated cross-linking reactions in the cell wall and may, in this capacity, play a role in the regulation of plant growth.Abbreviations AG
1-aminoguanidine
- AT
3-amino-1,2,4-triazole
-
-HEH
-hydroxyethylhydrazine
- DAO(s)
diamine oxidase(s)
- PAO(s)
polyamine oxidase(s)
- Put
putrescine
- Spd
spermidine
- Spm
spermine
The authors wish to thank Nancy Piatczyc for the technical assistance with electron-microscopy studies. We are grateful to Dr. Stanley J. Roux, University of Texas at Austin, for providing us with samples of maize cell-wall exudates. This work was supported by grants to R.D.S from the National Aeronautics and Space Administration (NAGW-1049 and NAGW-1382). 相似文献
3.
Occurrence of diamine oxidase in the apoplast of pea epicotyls 总被引:4,自引:0,他引:4
Most of the diamine oxidase (EC 1.4.3.6) present in pea (Pisum sativum L. cv. Rondo) epicotyls is found in the fluid obtained by centrifuging pea epicotyl sections previously infiltrated under vacuum with a buffer solution. No detectable amount of the cytoplasmic enzyme glucose-6-phosphate dehydrogenase is present in this fluid, showing that there is very little contamination by cell contents. Polyacrylamide-gel electrophoresis and specific-activity data indicate that diamine oxidase is the most plentiful protein in the extracellular solution obtained from pea epicotyl sections and that an active process is involved in the selective transfer of the enzyme outside the cell. The possible involvement of diamine oxidase in the supply of H2O2 to peroxidase-catalyzed reactions occurring inside the cell wall is discussed.Abbreviations DAO
diamine oxidase
- Glc6P
glucose-6-phosphate 相似文献
4.
R Manjunath S I Chung A B Mukherjee 《Biochemical and biophysical research communications》1984,121(1):400-407
Uteroglobin, a progesterone induced, pregnancy related protein, can be incorporated into higher molecular weight proteins by human placental Factor XIIIa. This process is time dependent, requires CaCl2 and can be inhibited by the addition of polylysine, dansylcadavarine or histamine. Crosslinking of uteroglobin into higher molecular weight proteins can also be brought about by guinea pig liver transglutaminase. Such a process may be involved in the modification of epididymal spermatozoa to suppress their antigenicity. 相似文献
5.
The involvement of amino acid residues previously proposed on the basis of structural data to have roles in the ferroxidase and diamine oxidase activities of human ceruloplasmin was investigated. Variants of human ceruloplasmin, in which residues proposed to be involved in electron transfer and/or iron-binding had been altered by site-directed mutagenesis, were expressed in HEK293 cells. E633A and E597A/H602A variants exhibited reduction in both activities by 50–60% compared to recombinant wild-type ceruloplasmin. The variant E935A/H940A had reduced ferroxidase activity (50%) but unaltered diamine oxidase activity, whereas the variant E971A exhibited enhanced diamine oxidase activity. For the L329M variant, both activities were identical to those of wild-type ceruloplasmin. 相似文献
6.
Bjelaković G Beninati S Pavlović D Sokolović D Stojanović I Jevtović T Bjelaković GB Nikolić J Basić J 《Amino acids》2007,33(3):525-529
Summary. Our study was undertaken to elucidate the effects of selenomethionine (SeMet) on polyamine metabolism in regenerating rat
liver tissue, as useful model of rapidly growing normal tissue. We have examined the levels of spermine, spermidine and putrescine
in liver tissue. At the same time we have evaluated the activities of polyamine oxidase (PAO) and diamine oxidase (DAO), the
catabolic enzymes of polyamine metabolism.
The obtained results suggest that polyamine levels in regenerating liver tissue, at 7th day after two-thirds partial hepatectomy, were higher in comparison with control group. The administration of selenomethionine
to hepatectomized animals during seven days, in a single daily dose of 2.5 μg/100 g body weight, increases the amount of spermine
and spermidine; the level of putrescine does not change under the influence of SeMet in regenerating rat liver tissue.
PAO activity is lower in regenerating hepatic tissue than in control group. Supplementation of hepatectomized animals with
SeMet significantly decreases the activity of this enzyme. DAO activity was significantly higher in hepatectomized and in
operated animals treated with SeMet compared to the sham-operated and control ones.
The differential sensitivity observed in our model of highly proliferating normal tissue to SeMet, compared with the reported
anticancer activity of this molecule is discussed. 相似文献
7.
Guibin Ma Andrey Ilyukhin Julius Glaser Imre Tth Lszl Zkny 《Inorganica chimica acta》2001,320(1-2):92-100
The formation of three [Tl(en)n]3+ complexes (n=1–3) in a pyridine solvent has been established by means of 205Tl and 1H NMR. Their stepwise stability constants based on concentrations, Kn=[Tl(en)n 3+]/{[Tl(en)n−1 3+]·[en]}, at 298 K in 0.5 M NaClO4 ionic medium in pyridine, were calculated from 205Tl NMR integrals: log K1=7.6±0.7; log K2=5.2±0.5 and log K3=2.64±0.05. Linear correlation between both the 205Tl NMR shifts and spin–spin coupling 205Tl–1H versus the stability constants has been found and discussed. A single crystal with the composition [Tl(en)3](ClO4)3 was synthesized and its structure determined by X-ray diffraction. The Tl3+ ion is coordinated by three ethylenediamine ligands via six N-donor atoms in a distorted octahedral fashion. 相似文献
8.
Osmotic stress-induced changes in cell wall peroxidase activity and hydrogen peroxide level in roots of rice seedlings 总被引:1,自引:0,他引:1
The changes in activity of peroxidase (POD) extracted from the cellwalls and the level of H2O2 in rice seedling rootstreatedwith mannitol and their correlation with root growth were investigated.Increasing concentrations of mannitol from 92 to 276 mM, which isiso-osmotic with 50 to 150 mM NaCl, progressively reduced rootgrowth and increased POD activities extracted from the cell walls of riceroots.The reduction of growth was also correlated with an increase inH2O2 level. Both diamine oxidase (DAO) and NADHperoxidase(NADH-POD) are known to be responsible for the generation ofH2O2. Mannitol treatment increased DAO but not NADH-PODactivities in roots of rice seedlings, suggesting that DAO contributes to thegeneration of H2O2 in the cell walls of mannitol-treatedroots. An increase in the level of H2O2 and the activityof POD extracted from the cell walls of rice roots preceded root growthreduction caused by mannitol. An increase in DAO activity coincided with anincrease in H2O2 in roots caused by mannitol. Since DAOcatalyses the oxidation of putrescine, the demonstration that mannitolincreasesthe activity of DAO in roots is consistent with those that mannitol decreasesthe level of putrescine. In conclusion, cell-wall stiffening catalysed by PODispossibly involved in the regulation of root growth reduction caused bymannitol. 相似文献
9.
Natalie St. Fleur 《Inorganica chimica acta》2009,362(5):1571-1745
Several alkynyl(tricarbonyl)diaminerhenium complexes were prepared from corresponding halo complexes and silver acetylides. With the diamine N,N′-dimethylpiperazine the compounds were found to be sufficiently stable to allow synthetic transformations on the acetylide ligand as well as purification by chromatography and subsequent substitution of the diamine ligand by stronger ligands such as phenanthrolines or isocyanides. 相似文献
10.