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1.
Yan Li Heng Yin Qing Wang Xiaoming Zhao Yuguang Du Fenglan Li 《Carbohydrate polymers》2009,75(4):612-617
NO (nitric oxide) and H2O2 (hydrogen peroxide) are important signaling molecule in plants. Brassica napus L. was used to understand oligochitosan inducing production of NO (nitric oxide) and H2O2 (hydrogen peroxide) and their physiological function. The result showed that the production of NO and H2O2 in epidermal cells of B. napus L. was induced with oligochitosan by fluorescence microscope. And it was proved that there was an interaction between NO and H2O2 with L-NAME (NG-nitro-l-arg-methyl eater), which is an inhibitor of NOS (NO synthase) in mammalian cells that also inhibits plant NO synthesis, and CAT (catalase), which is an important H2O2 scavenger, respectively. It was found that NO and H2O2 induced by oligochitosan took part in inducing reduction in stomatal aperture and LEA protein gene expression of leaves of B. napus L. All these results showed that oligochitosan have potential activities of improving resistance to water stress. 相似文献
2.
The effect of hydrogen peroxide on the survival and activity of antioxidant and associated enzymes in Saccharomyces cerevisiae has been studied. A difference found in the response of wild-type yeast strains treated with hydrogen peroxide was probably
related to the different protective effects of antioxidant enzymes in these strains. Exposure of wild-type YPH250 cells to
0.25 mM H2O2 for 30 min increased activities of catalase and superoxide dismutase (SOD) by 3.4-and 2-fold, respectively. However, no activation
of catalase in the EG103 strain, as well as of SOD in the YPH98 and EG103 wild strains was detected, which was in parallel
to lower survival of these strains under oxidative stress. There is a strong positive correlation (R
2 = 0.95) between activities of catalase and SOD in YPH250 cells treated with different concentrations of hydrogen peroxide.
It is conceivable that catalase would protect SOD against inactivation caused by oxidative stress and vice versa. Finally, yeast cell treatment with hydrogen peroxide can lead to either a H2O2-induced increase in activities of antioxidant and associated enzymes or their decrease depending on the H2O2 concentration used or the yeast strain specificity.
Published in Russion in Biokhimiya, 2006, Vol. 71, No. 9, pp. 1243–1252. 相似文献
3.
Unicellular green algae have the ability to operate in two distinctly different environments (aerobic and anaerobic), and
to photosynthetically generate molecular hydrogen (H2). A recently developed metabolic protocol in the green alga Chlamydomonas reinhardtii permitted separation of photosynthetic O2-evolution and carbon accumulation from anaerobic consumption of cellular metabolites and concomitant photosynthetic H2-evolution. The H2 evolution process was induced upon sulfate nutrient deprivation of the cells, which reversibly inhibits photosystem-II and
O2-evolution in their chloroplast. In the absence of O2, and in order to generate ATP, green algae resorted to anaerobic photosynthetic metabolism, evolved H2 in the light and consumed endogenous substrate. This study summarizes recent advances on green algal hydrogen metabolism
and discusses avenues of research for the further development of this method. Included is the mechanism of a substantial tenfold
starch accumulation in the cells, observed promptly upon S-deprivation, and the regulated starch and protein catabolism during
the subsequent H2-evolution. Also discussed is the function of a chloroplast envelope-localized sulfate permease, and the photosynthesis–respiration
relationship in green algae as potential tools by which to stabilize and enhance H2 metabolism. In addition to potential practical applications of H2, approaches discussed in this work are beginning to address the biochemistry of anaerobic H2 photoproduction, its genes, proteins, regulation, and communication with other metabolic pathways in microalgae. Photosynthetic
H2 production by green algae may hold the promise of generating a renewable fuel from nature’s most plentiful resources, sunlight
and water. The process potentially concerns global warming and the question of energy supply and demand. 相似文献
4.
Alveolar macrophages secrete numerous mediators, playing an important role in host defence. Among these mediators, nitric
oxide (NO) and hydrogen peroxide (H2O2) are both involved in bactericidal killing and trigger the release of other cellular metabolites. We have analyzed the effect
of an atmosphere polluted with ozone (0.03–0.5 ppm v/v) on the monocytic cell line THP-1, as a model for alveolar macrophages,in vitro. NO and H2O2 were chosen to evaluate cell response to ozone. Cell injury was evaluated using lactate dehydrogenase (LDH) liberation into
the medium. An exposure to 0.5 ppm ozone proved to be more toxic to the cells, than 0.1 or 0.03 ppm, evidenced by more LDH
being liberated and cytotoxicity reaching values up to 64%. For all ozone concentrations, H2O2 production reached a peak value after 10–15 min of exposure, after which the concentration of extracellular H2O2 production diminished rapidly. The highest NO concentrations were measured with 0.5 ppm ozone, reaching a maximum value of
1460 nmol/L per 5×106 cells, which is 1.55 times higher than for nonexposed cells. Lower concentrations barely induced higher NO concentrations
compared to nonexposed cells. The results indicate that ozone effects not only the viability of human monocytes but also the
release of antibacterial and defense signaling molecules and suggest that ozone-mediated cytotoxicity may be related to the
secretion of NO and H2O2.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
5.
Li X Li H Pang X Feng H Zhi D Wen J Wang J 《Molecular and cellular biochemistry》2007,300(1-2):207-213
Production and localization of endogenous hydrogen peroxide (H2O2) were investigated in strains of Xanthomonas by histochemical analysis under electron microscopy. Even though the levels of endogenous H2O2 production were different among various strains, the produced H2O2 was localized in the cell wall of all Xanthomonas strains tested. The impairment of the level of endogenous H2O2 accumulation resulted in a significantly decreased growth rate of bacteria, regardless if the difference of the H2O2 level is originally present between wild type strains or caused by mutation of the ahpC gene of Xanthomonas. The endogenous accumulation of H2O2 positively correlates with the cell division. Interestingly, the accumulated H2O2 was also localized in the mesosome-like structure and nucleoids during the cell division cycle. Furthermore, results revealed
quantitative and dimensional changes of H2O2 accumulation in the two additional locations. These findings indicated that the additional locations of the accumulated H2O2 were closely associated with the process of cell division. Together, these results suggest that the endogenous H2O2 production plays an important role in cell proliferation of Xanthomonas. 相似文献
6.
Summary The in vivo induction of H2O2 production was tested on tobacco cell suspension cultures (Nicotiana tabacum cv. Bright Yellow-2). The measurement of H2O2 was based on the oxidation of 3,5-dichloro-2-hydroxybenzensulfonic acid by endogenous peroxidases and spectrophotometric detection after reaction with 4-aminoanti-pyrine. The phosphatase inhibitor cantharidin induced a transient increase in H2O2 synthesis. The timing of the H2O2 production, the level of induction by cantharidin and the background H2O2 production were dependent on the tobacco cell concentration used. A concentration curve of cantharidin revealed saturating kinetics for the H2O2 detection (E50=46 to 70 M, Emax=101 to 128 mol/h·g fresh weight). An inhibitor study with the tobacco BY-2 cells showed high inhibitions of the H2O2 induction with the flavin analogues diphenylene iodonium (I50=1.26M) and acridine orange and with membrane-permeative thiol reagents (N-ethyl maleimide, N-pyrene maleimide, iodoacetate); whereas the nonpermeative thiol reagentp-chloromercuribenzoic acid was ineffective. Therefore, the induction of H2O2 production with phosphatase inhibitors (cantharidin) showed comparable properties to the elicitor-induced oxidative-burst response in other plant cells.Abbreviations AcOr
acridine orange
- AOS
active-oxygen species
- BY-2
Bright Yellow-2
- pCMBS
p-chloromercuribenzoic acid
- DHBS
3,5-dichloro-2-hydroxybenzenesulfonic acid
- DMSO
dimethylsulfoxide
- DPI
diphenylene iodonium
- EtOH
ethanol
- H2O2
hydrogen peroxide
- HRP
horseradish peroxidase
- MS
Murashige and Skoog
- NEM
N-ethyl maleimide
- NPM
N-pyrene maleimide
- O
2
–
superoxide
- SOD
superoxide dismutase 相似文献
7.
Effects of short-term heat stress on oxidative damage and responses of antioxidant system in Lilium longiflorum 总被引:2,自引:0,他引:2
This paper aims to determine the changes in reactive oxygen species (ROS) and the responses of the lily (Lilium longiflorum L.) antioxidant system to short-term high temperatures. Plants were exposed to three levels of heat stress (37°C, 42°C, 47°C)
for 10 h when hydrogen peroxide (H2O2) and superoxide (O2−) production rate along with membrane injury indexes, and changes in antioxidants were measured. Compared with the control
(20°C), electrolyte leakage and MDA concentration varied slightly after 10 h at 37°C and 42°C, while increased significantly
at 47°C. During 10 h at 37°C and 42°C, antioxidant enzyme activities, such as SOD, POD, CAT, APX and GR, were stimulated and
antioxidants (AsA and GSH concentrations) maintained high levels, which resulted in low levels of O2− and H2O2 concentration. However, after 10 h at 47°C, SOD, APX, GR activities and GSH concentration were similar to the controls, while
POD, CAT activities and AsA concentration decreased significantly as compared with the control, concomitant with significant
increase in O2− and H2O2 concentrations. In addition, such heat-induced effects on antioxidant enzymes were also confirmed by SOD and POD isoform,
as Cu/ZnSOD maintained high stability under heat stress and the intensity of POD isoforms reduced with the duration of heat
stress, especially at 47°C. It is concluded that in lily plants, the oxidative damage induced by heat stress was related to
the changes in antioxidant enzyme activities and antioxidants. 相似文献
8.
Plant peroxidases (POD) reduce hydrogen peroxide (H2O2) in the presence of an electron donor. Extracellular POD can also induce H2O2 production and may perform a significant function in responses to environmental stresses via the regulation of H2O2 in plants. We previously described the isolation of 10 POD cDNA clones from cell cultures of sweetpotato (Ipomoea batatas). Among them, the expression of the swpa4 gene was profoundly induced by a variety of abiotic stresses and pathogenic infections (Park et al. in Mol Gen Genome 269:542–552
2003; Jang et al. in Plant Physiol Biochem 42:451–455 2004). In the present study, transgenic tobacco (Nicotiana tabacum) plants overexpressing the swpa4 gene under the control of the CaMV 35S promoter were generated in order to assess the function of swpa4
in planta. The transgenic plants exhibited an approximately 50-fold higher POD specific activity than was observed in control plants.
Both transient expression analysis with the swpa4-GFP fusion protein and POD activity assays in the apoplastic washing fluid
revealed that the swpa4 protein is secreted into the apoplastic space. In addition, a significantly enhanced tolerance to
a variety of abiotic and biotic stresses occurred in the transgenic plants. These plants harbored increased lignin and phenolic
content, and H2O2 was also generated under normal conditions. Furthermore, they showed an increased expression level of a variety of apoplastic
acidic pathogenesis-related (PR) genes following enhanced H2O2 production. These results suggest that the expression of swpa4 in the apoplastic space may function as a positive defense signal in the H2O2-regulated stress response signaling pathway. 相似文献
9.
In the last few years, the role of reactive oxygen species as signaling molecules has emerged, and not only as damage-related
roles. Here, we analyzed how root hydraulic properties were modified by different hydrogen peroxide (H2O2) concentrations applied exogenously to the root medium. Two different experimental setups were employed: Phaseolus vulgaris plants growing in hydroponic or in potted soils. In both experimental setups, we found an increase of root hydraulic conductance
(L) in response to H2O2 application for the first time. Twenty millimolar was the threshold concentration of H2O2 for observing an effect on L in the soil experiment, while in the hydroponic experiment, a positive effect on L was observed at 0.25 mM H2O2. In the hydroponic experiment, a correlation between increased L and plasma membrane aquaporin amount and their root localization was observed. These findings provide new insights to study
how several environmental factors modify L. 相似文献
10.
Massa S. Petruccioli M. Brocchi Giada F. Altieri Clelia Sinigaglia Milena Spano G. 《World journal of microbiology & biotechnology》2001,17(3):287-291
The antibacterial effect of different glucose oxidase (GOX)/glucose combinations was studied on two food-poisoning organisms, enterotoxic Escherichia coli PM 015 and Salmonella derby BP 177. Growth of E. coli in nutrient broth (NB) was clearly inhibited by 4.0 mg/ml glucose after 24 h when combined with 2.0 U/ml GOX and after 48 h when combined with 0.5 or 1.0 U/ml GOX. Salmonella derby was more resistant than E. coli, but showed clear growth inhibition only after 48 h when inoculated in tubes where 2 mg glucose/ml and 2 U GOX/ml (or 4 mg glucose/ml and 1 U GOX/ml) were combined. In order to understand if the enzyme effect on microbial growth can be attributed to hydrogen peroxide or to pH decrease as a result of the production of gluconic acid, catalase (CAT) was added to GOX/glucose system. Since CAT decomposes H2O2 to H2O and O2, the antibacterial effect was ascribed to a pH decrease as a result of gluconic acid in the system. 相似文献
11.
Anna Źróbek-Sokolnik Han Asard Kamilla Górska-Koplińska Ryszard J. Górecki 《Acta Physiologiae Plantarum》2009,31(1):43-49
Generation of reactive oxygen species (ROS) constitutes an important first reaction under many stress conditions in plants.
We demonstrate that Nicotiana tabacum L. cv. Bright Yellow 2 (TBY-2) cells in suspension cultures, generate superoxide radical and hydrogen peroxide upon treatment
with cadmium and zinc. Addition of catalase and N,N-diethyldithiocarbamate (DDC) decreased the level of H2O2, whereas superoxide dismutase (SOD) induced a slight increase of the H2O2 production. The effects of catalase, DDC and SOD on the heavy metal-induced ROS production indicate that it occurs outside
of the cells, and that at least part of the hydrogen peroxide is produced by dismutation of the superoxide radical (O2
·−). The effect of pretreatment of the cell cultures with commonly used mammalian NADPH oxidase inhibitors was also tested.
Strong inhibitions of cadmium and zinc-mediated ROS production were obtained with the flavoprotein inhibitors—diphenylene
iodonium (DPI) and quinacrine and with an inhibitor of b-type cytochromes—imidazol. Membrane permeable-N-ethyl maleimide (NEM) and iodoacetate, and membrane non-permeable thiol reagents—para-chloromercuribenzoic acid (pCMBS) also
inhibited the ROS production. These results suggested that the enzyme responsible for cadmium and zinc-induced ROS production
in tobacco cells contains a flavocytochrome. They also show the importance of intra- and extracellular thiol groups in the
observed stress reaction. The induction of ROS production with heavy metals showed properties comparable to the elicitor-induced
oxidative burst in other plant cells. 相似文献
12.
In Arabidopsis thaliana leaves a strong increase of H2O2 content was induced by application of methyl jasmonate (JAMe) through the root system, but the induction only slightly depended
on JAMe concentration. The activity of superoxide dismutase and ascorbic acid peroxidase increased at lower JAMe concentrations
and decreased at higher ones. Catalase activity decreased proportionally to JAMe concentration (in comparison with control
plants). The sum of ascorbic acid and dehydroascorbate content at 10−6 M JAMe was similar to the control, but at higher concentrations it increased, especially due to a higher ascorbate accumulation.
Methyl jasmonate applied directly to the extract of leaves (in vitro experiment) also induced a strong increase in H2O2 level, even at a low concentration (10−8 M). Since lower JAMe concentrations induced weak superoxide dismutase and did not change catalase and peroxidase activity,
it is suggested that in this case a high level of hydrogen peroxide was not the result of the activity of the mentioned enzymes.
JAMe-induction of H2O2 increase at the highest JAMe concentration resulted from SOD activity. Our in vivo and in vitro experiments suggest that jasmonate can influence oxidative stress not only through gene expression but also by its direct
effect on enzyme activity. 相似文献
13.
14.
Plantago is the most important genus of Plantaginaceae family and is used in traditional medicine around the world for different purposes.
Plantago coronopus L., Plantago major L., Plantago media L. and Plantago lanceolata L. are most commonly used species of Plantago in traditional medicine in Turkey. The main goal of this study was to investigate the eventual anti-mitotic and anti-genotoxic
effects of P. lanceolata L. leaf aqueous extracts (15 g/L and 30 g/L) on Allium cepa L. root tip meristem cells which were treated with 0.7% hydrogen peroxide. For this purpose, two different experiments were
performed under the same conditions. In the first experiment, Allium cepa onion bulbs were treated with 0.7% H2O2 for 1 h. After the H2O2 treatment, the onion bulbs were treated with two different concentrations (15 g/L and 30 g/L) of P. lanceolata extracts for 24 h. In the second experiment, A. cepa onion bulbs were treated with two different extract concentrations (15 g/L and 30 g/L) for 24 h and then with 0.7% H2O2 for 1 h. The test concentrations were determined according to doses which are recommended in alternative medicinal usage
by people. As positive and negative control 0.7% H2O2 and tap water was used, respectively. As a result, it was determined that aqueous extracts reduced mitotic index and chromosome
aberrations in treatment groups in comparison with controls. These results showed that P. lanceolata aqueous extracts have anti-mitotic and anti-genotoxic effects. 相似文献
15.
Jacek Patykowski 《Acta Physiologiae Plantarum》2006,28(6):589-598
The aim of the research was to estimate the sensitivity of tomato tissue and spore from necrotrophic isolate of B. cinerea on H2O2. The influence of exogenic H2O2 and B. cinerea on plant tissue and on the activity of peroxidases (PO), catalase (CAT) and superoxide dismutase (SOD) in apoplastic tomato
leaves fraction were investigated.
It was proved that 40 mM H2O2 damaged the cells of a host, and inhibited in vitro germination of B.cinerea spores. Complete inhibition of germination was observed after the use 100 mM H2O2. In the presence of spores H2O2 was decomposed to H2O and O2. Trace activity of catalase was observed in a solution of spores used for inoculation. Necrosis which appeared on the leaves
after 40 mM H2O2 treatment resembled hypersensitive response. On the leaves pretreated at this concentration the development of infection
was observed. The H2O2 concentration harmful for the tissues, stimulated the PO activity measured with NADH — responsible for generation of ·O
2
−
, as well as with syringaldazine (S) and ferulic acid (FA), substrates characteristics of forms lignifying and strengthening
the cell wall. Clear increase in CAT activity, resulting from infection and early pretreatment with H2O2 was observed in apoplast. No effect on SOD activity was observed.
A hypothesis may be put forward, that germinating spores produce enzymes which allow them to decompose H2O2 generated in apoplast, so there is little likelihood that B. cinerea can be directly inhibited by reactive oxygen forms (ROS) during initial stages of infection. Necrotic lesions resembling
HR generated by exogenous H2O2 as well as induction of activity of apoplastic plant enzymes, particularly PO connected with strengthening and lignification
of cell wall, were not sufficient factors to inhibit fungal expansion. 相似文献
16.
Ni Chen Yan Liu Xin Liu Juan Chai Zhong Hu Guangqin Guo Heng Liu 《Plant Molecular Biology Reporter》2009,27(3):321-333
17.
Adriana G. Prat Caroline Bolter Ulises Chavez Charles Taylor William Chefurka Julio F. Turrens 《Free radical biology & medicine》1991,11(6)
One of the most precise methods of determining hydrogen peroxide (H2O2) formation by biological systems is based on measuring the rate of enzyme-substrate complex formation between H2O2 and cytochrome c peroxidase (CCP). The main problem with this method is that CCP is not commercially available and has to be prepared in the laboratory. We have modified some currently available methods for purifying a highly active preparation of CCP in about 4 d. It includes a batch extraction of protein using DEAE-sepharose followed by concentration either by lyophilization or by passing the extract through a small DEAE-sepharose column instead of by ultrafiltration. The concentrated preparation is passed through a Sephadex G-75 column and the final CCP crystallized against water. The final preparations had a purity index (PI, ratio of absorbance at 408 nm/280 nm, equivalent to heme/protein ratio) above 1.2. These changes make the overall procedure very simple, preserving enzyme activity and spectral properties. In addition, we point out that special care has to be taken to eliminate cytochrome c from crude CCP extracts. Cytochrome c not only introduces an artifact when determining PI, but is also may act as a hydrogen donor for CCP when monitoring H2O2 formation, thus decreasing the sensitivity of this method. 相似文献
18.
Hydrogen peroxide and lignification 总被引:26,自引:0,他引:26
The production of hydrogen peroxide in plant tissue is demonstrated quickly with a simple histochemical test. The test solution, 50 mM potassium iodide in a 4% (w/v) potato starch suspension, is applied to the cut surface of the tissue to be tested. Hydrogen peroxide oxidizes iodide ions to iodine; the iodine is complexed by the starch to form a blue-purple color. This test detects hydrogen peroxide production in cells undergoing lignification, i.e. tracheary elements and phloem fibers, and in some epidermal cells. In addition there is a rapid production of hydrogen peroxide in crushed cells. The test is negative under (i) anaerobic conditions and (ii) in the presence of catalase. 相似文献
19.
Roman Przymusiński Renata Rucińska-Sobkowiak Bogna Ilska Edward A. Gwóźdź 《Acta Physiologiae Plantarum》2007,29(5):411-416
In an earlier work using tissue printing method, we found that the PR-10 stress protein was observed in leaf petiole of lupin
seedling where lead was not detected (Przymusiński et al. 2001). These results suggested the presence of substance(s) mediating a signal transduction from directly affected cells to distant
organs. As the hydrogen peroxide was found to be involved in signal transduction pathway, in the present paper, we analysed
the level of H2O2 in the organ of lupin seedlings exposed to Pb2+ with spectrophotometric method and tissue printing technique. It was unequivocally demonstrated that the level of H2O2 and the activity of peroxidase increased in every tested organ of lead-treated lupin seedling. Both the level of H2O2 and the activity of POX were correlated with amount of Pb2+ ions in the cells (Przymusiński et al. 2001) and decreased in tissues more and more distant from the site of metal application. On the other hand, there was no correlation
between the histological localization of H2O2 and peroxidase. Our results seem to confirm the hypothesis that H2O2 may act as a signalling substance involved in the induction of PR protein synthesis. It was indicated that there is high
degree of correlation between the localization of H2O2 and the histological localization of PR-10 proteins (Przymusiński et al. 2001) in every tested organ of lupin seedling. The presented hypothesis is also supported by the fact that H2O2 and PR-10 proteins are detected in organs and tissues where Pb2+ was not found at all. 相似文献
20.
Linchuan Zhao Liangen Shi 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2009,152(4):339-345
Recent work has demonstrated that hydrogen peroxide functions as a signaling molecule controlling different essential processes in plants and mammals, which can be produced by superoxide dismutase (SOD) and xanthine oxidase (XO) and decomposed by catalase (CAT), respectively. Progeny diapause of the silkworm, Bombyx mori, is induced by diapause hormone (DH) and the expression of DH gene in the maternal generation has been determined. In order to investigate the relationship between the metabolism of H2O2 and the expression of DH gene, level of H2O2 and activities of SOD, XO and CAT between univoltine and polyvoltine strains, which can produce diapause and non-diapause eggs, respectively, at embryonic and pupal stages were measured. Our results showed that there were significant differences in the metabolism of hydrogen peroxide between two strains and between embryonic and pupal stages. Compared to polyvoltine strain, level of hydrogen peroxide in univoltine strain was significantly higher from stage 19 to stage 21 but lower from stage 24 to stage 29 and the whole pupal stage (Fig. 1). Variations of hydrogen peroxide indicated that hydrogen peroxide may be involved in the active release of DH and the progeny diapause decision by DH rather than the expression of DH gene. 相似文献