共查询到20条相似文献,搜索用时 15 毫秒
1.
Jacques B. Baldensperger 《Archives of microbiology》1978,119(3):237-244
Superoxide dismutase has been purified to homogeneity from aerobically grown Thiobacillus denitrificans strain RT. It has a molecular weight of 43,000, is composed of two identical subunits which are not covalently bound, and contains 1.35 atom of iron per molecule. Absorption spectra and amino acid analysis are similar to those of other Fe-superoxide dismutases from bacteria. Aerobically and anaerobically grown cells contain the same Fe-enzyme with similar levels of activity. Manometric sulfite oxidation measurements suggest for the enzyme a protective function of sulfite against the autooxidation initiated by superoxide free radicals.Non-Standard Abbreviations DMSO
dimethyl sulfoxide
- SDS
sodium dodecyl sulfate
- SOD
superoxide dismutase 相似文献
2.
Superoxide dismutase activity was measured in different stages of growth of filarial parasites (human and cattle). The activity
was almost undetected or very low in microfilarial stage but in adult worms, the enzyme activity was high. The enzyme was
characterized to be a Cu/Zn superoxide dismutase. Most of the enzyme activity was associated with a detergent extractable
fraction of adult (Setaria) parasite. The enzyme was also detected in thein vitro released products of adult worms. The superoxide dismutase activity was completely inhibited with IgG antibody from chronic
filarial patients in contrast to IgG from normal people. Filarial patients particularly have high IgG and IgM antibody levels
to purified enzyme. However, individuals from non-filarial regions of Orissa are sero-negative for superoxide dismutase antibodies.
Antibody response to superoxide dismutase could thus be used for filarial diagnosis. 相似文献
3.
Purification and Characterization of Cu,Zn Superoxide Dismutase from Ark Shell Scapharca broughtonii
《Bioscience, biotechnology, and biochemistry》2013,77(11):2211-2216
A superoxide dismutase has been purified to apparent homogeneity from the muscular tissue of the ark shell, Scapharca broughtonii, by ammonium sulfate fractionation, and consecutive column chromatographies using DEAE-Sephadex and Sephadex G-100. This enzyme has a molecular weight of 71,700 and is composed of two identical subunits of M r 35,800, which are joined by noncovalent interactions. The purified enzyme was stable over the range of pH 5.0-10.0 at 4°C for 24 h and at temperatures below 45°C. Cyanide at 0.1 and 1 mM inhibited the activity of the superoxide dismutase 56 and 100%, but 5 mM azide caused 8% inhibition. The optical spectrum of this enzyme had a maximum at 265 nm, and the amino acid composition of the enzyme was similar to that of the other Cu, Zn superoxide dismutases except for the contents of threonine, serine, proline, and leucine. Atomic absorption spectroscopy showed that this enzyme has approximately 2 atoms of Cu2+ and Zn2+ per mole of enzyme. These results indicate that the purified enzyme from ark shell, Scapharca broughtonii, is a Cu, Zn superoxide dismutase. 相似文献
4.
Iron superoxide dismutase (Fe-SOD; EC 1.15.1.1) was isolated from the nitrogen-fixing cyanobacterium Anabaena cylindrica Lemm. Polyacrylamide gel electrophoresis separated the purified protein into three closely running, enzymatically active bands. The molecular weight of the enzyme was estimated by gel filtration to be about 40 kDa. Polyclonal antibodies were produced by immunization of rabbits with the isolated enzyme, and were purified on a column of protein A-Sepharose. The Fe-SOD antibody reacted with the purified Fe-SOD and also specifically recognized the protein in extracts of A. cylindrica. In the extracts, anti-Fe-SOD did not cross-react with Mn-SOD, an enzyme which belongs to an SOD class displaying high homology of primary and three-dimensional structure with respect to Fe-SOD. Iron superoxide dismutase was localized in heterocysts by immunogold labeling and transmission electron microscopy. These results are the first in-situ evidence for the presence of SOD in the cells specialized for nitrogenase activity.Abbreviations ELISA
enzyme-linked immunosorbent assay
- SDS
sodium dodecyl sulfate
- SOD
superoxide dismutase
- PAGE
polyacrylamide gel electrophoresis
- pI
isoelectric point
This work was supported by a C.N.R. grant. We are grateful to Dr. A. De Martino for technical assistance. 相似文献
5.
Manuel Sanchez-Moreno Emilio Entrala Dirk Janssen Antonio Osuna 《Bioscience reports》1994,14(2):83-90
Copper-zinc superoxide dismutase fromAscaris suum (Nematoda) was purified in a new, more efficient, and faster manner. The process included differential centrifugation, fractionation with ammonium sulfate, and sodium dodecyl sulfate-polyacrylamide electrophoresis, yielding a 340-fold purification (specific activity of 47 units/mg). Optimal storage conditions, optimal pH range, thermostability, molecular weight and ultravioltet-visible absorption spectrum of the enzyme are described, and a new enzymatic model for pharmacological screening is suggested.Abbreviations (SOD)
Superoxide dismutase
- (EDTA)
Ethylenediaminetetraacetic acid
- (SDS)
Sodium dodecyl sulfate
- (NBT)
p-nitrotetrazolium blue
- (UV)
Ultraviolet 相似文献
6.
A manganese-containing superoxide dismutase (EC 1.15.1.1) was purified to homogeneity from a higher plant for the first time. The enzyme was isolated fromPisum sativum leaf extracts by thermal fractionation, ammonium sulfate salting out, ion-exchange and gel-filtration column chromatography, and preparative polyacrylamide gel electrophoresis. Pure manganese superoxide dismutase had a specific activity of about 3,000 U mg-1 and was purified 215-fold, with a yield of 1.2 mg enzyme per kg whole leaf. The manganese superoxide dismutase had a molecular weight of 94,000 and contained one g-atom of Mn per mol of enzyme. No iron and copper were detected. Activity reconstitution experiments with the pure enzyme ruled out the possibility of a manganese loss during the purification procedure. The stability of manganese superoxide dismutase at-20°C, 4°C, 25°C, 50°C, and 60°C was studied, and the enzyme was found more labile at high temperatures than bacterial manganese superoxide dismutases and iron superoxide dismutases from an algal and bacterial origin.Abbreviations NBT
nitro blue tetrazolium
- SOD
superoxide dismutase (EC 1.15.1.1) 相似文献
7.
Gabbianelli R Signoretti C Marta I Battistoni A Nicolini L 《Journal of biotechnology》2004,109(1-2):123-130
Superoxide dismutases are ubiquitous enzymes which play an important role in protecting cells against oxidative damage and which have also been shown to contribute to the pathogenicity of many bacterial species. Here we demonstrate that Vibrio cholerae, the causative agent of cholerae, expresses an active periplasmic Cu,Zn superoxide dismutase. Moreover, we have set up an expression system yielding large amounts of V. cholerae recombinant Cu,Zn superoxide dismutase in the periplasm of Escherichia coli and a procedure to obtain the enzyme in a highly purified form. Unlike the bovine enzyme, V. cholerae Cu,Zn superoxide dismutase has been proved to be highly resistant to inactivation by hydrogen peroxide. This property, which appears to be common to other bacterial enzymes of this class, might improve the ability of Cu,Zn superoxide dismutase to protect bacteria against the reactive oxygen species produced by phagocytes. 相似文献
8.
Exposure to 2,4,6-trinitrotoluene (TNT) has been shown to cause induction of cataract in which oxidative stress plays a critical role. From bovine lens we purified to homogeneity and identified an enzyme that catalyzes the reduction of TNT, resulting in the production of reactive oxygen species. The final preparation of TNT reductase showed a single band with a subunit molecular weight of 38 kDa on SDS-PAGE. Sequence data from peptides obtained by digestion with lysylendopeptidase Achromobacter protease I (API) revealed that TNT reductase is identical to zeta-crystallin. Superoxide anions were formed during reduction of TNT by zeta-crystallin, though negligible enzyme activity or protein content for superoxide dismutase, a superoxide scavenging enzyme, was found in the lens. Thus, the present results suggest that the induction of cataracts by TNT may be associated with increased oxidative stress, as a result of reductive activation of TNT generating superoxide anions, there being minimal antioxidant enzyme activity for defense against reactive oxygen species exogenously produced in the lens. 相似文献
9.
Ning-Ning Song Yan Zheng Shi-Jin E Duo-Chuan Li 《Journal of microbiology (Seoul, Korea)》2009,47(1):123-130
A superoxide dismutase (SOD) gene of Thermoascus aurantiacus var. levisporus, a thermophilic fungus, was cloned, sequenced, and expressed in Pichia pastoris and its gene product was characterized. The coding sequence predicted a 231 residues protein with a unique 35 amino acids
extension at the N-terminus indicating a mitochondrial-targeting sequence. The content of Mn was 2.46 μg/mg of protein and
Fe was not detected in the purified enzyme. The enzyme was found to be inhibited by NaN3, but not by KCN or H2O2. These results suggested that the SOD in Thermoascus aurantiacus var. levisporus was the manganese superoxide dismutase type. In comparison with other MnSODs, all manganese-binding sites were also conserved
in the sequence (H88, H136, D222, H226). The molecular mass of a single band of the enzyme was estimated to be 21.7 kDa. The
protein was expressed in tetramer form with molecular weight of 68.0 kDa. The activity of purified protein was 2,324 U/mg.
The optimum temperature of the enzyme was 55°C and it exhibited maximal activity at pH 7.5. The enzyme was thermostable at
50 and 60°C and the half-life at 80°C was approximately 40 min. 相似文献
10.
Superoxide dismutase has been purified to homogeneity from Lens esculenta cotyledons and shoots. The two forms appeared to be identical. The purified enzyme contained two electrophoretically distinct bands. It contained two ions of Cu and two ions of Zn. Gel filtration experiments indicate a molecular weight of about 33,000. The spectrum of ultraviolet and visible regions and electron paramagnetic resonance were similar to those of Cu-Zn mammalian superoxide dismutase. 相似文献
11.
N. N. Gessler A. V. Sokolov V. Ya. Bykhovsky T. A. Belozerskaya 《Applied Biochemistry and Microbiology》2002,38(3):205-209
The addition of menadione into the medium during cultivation ofNeurospora crassa in the dark activated its constitutive superoxide dismutase. Exposure to light not only activated superoxide dismutase and catalase, but also increased the content of neurosporaxanthin. Superoxide dismutase activity in the mixed (+/–) cultures of Blakeslea trispora synthesizing -carotene in the dark was much lower than that inNeurospora crassa. The superoxide dismutase activity and catalase activity further decreased in oxidative stress with a parallel increase in the content of -carotene. Our results indicate that neurosporaxanthin possesses photoprotective properties in Neurospora crassa. In Blakeslea trispora (+/–) fungi, -carotene acts as a major antioxidant during inactivation of enzymes that detoxify reactive oxygen species. 相似文献
12.
Fumiyoshi Abe Takeshi Miura Takahiko Nagahama Akira Inoue Ron Usami Koki Horikoshi 《Biotechnology letters》2001,23(24):2027-2034
Thirteen yeast strains were isolated from deep-sea sediment samples collected at a depth of 4500 m to 6500 m in the Japan Trench. Amongst them, strain N6 possessed high tolerance against Cu2+ and could grow on yeast extract/peptone/dextrose/agar containing 50 mM CuSO4. Analysis of the 18S rDNA sequence indicates strain N6 belongs to the genus Cryptococcus. In contrast, the type strain of C. albidus, a typical marine yeast Rhodotorula ingeniosa and Saccharomyces cerevisiae did not grow at high concentrations of CuSO4. Superoxide dismutase (SOD) catalyzes the scavenging of superoxide radicals. The activity of SOD in cell extract of strain N6 was very weak (<1 mU g–1 total protein) when the strain was grown in the absence of CuSO4. However, the activity was stimulated (25.8 mU g–1 total protein) when cells were grown with 1 mM CuSO4 and further enhanced to 110 mU g–1 total protein with 10 mM CuSO4. Catalase activity was increased only 1.4 or 1.1-fold with 1 mM or 10 mM CuSO4 in the growth medium, respectively. These results suggest that SOD may have a role in the defensive mechanisms against high concentrations of CuSO4 in strain N6. 相似文献
13.
Superoxide dismutase catalyzes the breakdown of superoxide radical anion and provides the first line of defense against oxygen
toxicity. Its vital importance has made it the subject of numerous investigations. Several assays have been proposed for the
detection and quantitation of superoxide dismutase activity, but their use has remained controversial and no comparative studies
have been reported. In this investigation, three commonly used methods for the measurement of superoxide dismutase activity
were compared to assay the enzyme in Crocus sativus L. corm extract. The methods, based on the competition between the enzyme itself and a superoxide scavenger, involved cytochrome
c reduction, nitro blue tetrazolium reduction, and pyrogallol autooxidation, respectively. Because of its accuracy, reproducibility,
simplicity, and cost benefit, the latter method was preferred.
The text was submitted by the authors in English. 相似文献
14.
Hua YW Chi MC Lo HF Hsu WH Lin LL 《Journal of industrial microbiology & biotechnology》2004,31(6):273-277
Bacillus stearothermophilus leucine aminopeptidase II (LAPII) was fused at its C-terminal end with the raw-starch-binding domain of Bacillus sp. strain TS-23 -amylase. The chimeric enzyme (LAPsbd), with an apparent molecular mass of approximately 61 kDa, was overexpressed in IPTG-induced Escherichia coli cells and purified to homogeneity by nickel-chelate chromatography. The purified enzyme retained LAP activity and adsorbed raw starch. LAPsbd was stable at 70°C for 10 min, while the activity of wild-type enzyme was completely abolished under the same environmental condition. Compared with the wild-type enzyme, the twofold increase in the catalytic efficiency for LAPsbd was due to a 218% increase in the k
cat value. 相似文献
15.
Superoxide dismutase activity was demonstrated for 6 strains of 3 propionibacteria species. Rather high level of superoxide dismutase activity found in propionibacteria was in accordance with high level of catalase activity reported for propionibacteria previously. Both these activities were shown to have cytozolic localization. For the first time peroxidase activity was detected in gel-fractionated crude cell extracts of propionibacteria. The ability to produce superoxide radicals in NADH-dependent oxidation system was revealed for three strains of the bacteria. The level of superoxide production by the membrane particles of the propionic acid bacteria correlated with the levels of superoxide dismutase and catalase activities and was the lowest for Propionibacterium shermanii. The ability to perform monovalent oxygen reduction during succinate oxidation was not revealed. The intact cells of P. globosum, P. vannielii, P. shermanii apparently did not excrete superoxide radicals into culture fluid during respiration. 相似文献
16.
Glutamine synthetase (GS) (EC 6.3.1.2) has been purified 67-fold fromNocardia corallina. The apparentM
r of the GS subunit was approximately 56,000. Assuming the enzyme is a typical dodecamer this indicates a particle mass for the undissociated enzyme of 672,000. The GS is regulated by adenylylation and deadenylylation, and subject to feedback inhibition by alanine and glycine. The pH profiles assayed by the -glutamyl transferase method were similar for NH4
+-treated and untreated cell extracts and an isoactivity point was not obtained from these curves. GS activity was repressed by (NH4)2SO4 and glutamate. Cells grown in the presence of glutamine, alanine, proline and histidine had enhanced levels of GS activity. The GS ofN. corallina cross-reacted with antisera prepared against GS from a Gram-negativeThiobacillus ferrooxidans strain but not with antisera raised against GS from a Gram-positiveClostridium acetobutylicum strain. 相似文献
17.
Superoxide Dismutases: II. Purification and Quantitative Relationship with Water-soluble Protein in Seedlings
下载免费PDF全文
![点击此处可从《Plant physiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Superoxide dismutase was purified from pea (Pisum sativum L., cv. Wando) seeds and corn (Zea mays L., cv. Michigan 500) seedlings. The purified pea enzyme eluting as a single peak from gel exclusion chromatography columns contained the three electrophoretically distinct bands of superoxide dismutase characterizing the crude extract. The purified corn enzyme eluted as the same peak as the pea enzyme, and contained five of the seven active bands found in the crude extract. The similar molecular weights and the cyanide sensitivities of these bands indicated that they are probably isozymes of a cupro-zinc superoxide dismutase. One of the remaining corn bands was shown to be a peroxidase. 相似文献
18.
Purification and properties of mangano-superoxide dismutase from a strain of alkaliphilic Bacillus 总被引:1,自引:0,他引:1
Yoshihiro Hakamada Kenzo Koike Tohru Kobayashi Susumu Ito 《Extremophiles : life under extreme conditions》1997,1(2):74-78
A mangano-superoxide dismutase (EC 1.15.1.1) was purified to homogeneity from a strain of alkaliphilic Bacillus for the first time. The purified protein, with an isoelectric point of pH 4.5, had a molecular mass of approximately 50 kDa
and consisted of two identical subunits (25 kDa). The N-terminal amino acid sequence was Ala-Tyr-Lys-Leu-Pro-Glu-Leu-Pro-Tyr-Ala-Ala-Asn-Ala-Leu-Glu-Pro-His-Ile-Asp-Glu-Ala.
The optimum pH and temperature for the reaction were 7.5 and 35°C, respectively. The properties of the superoxide dismutase
were compared with those of the enzyme from thermophilic Bacillus stearothermophilus.
Received: September 3, 1996 / Accepted: October 4, 1996 相似文献
19.
Miyamoto E Watanabe F Charles TC Yamaji R Inui H Nakano Y 《Archives of microbiology》2003,180(2):151-154
High activity (>60 munit/mg protein) of 5-deoxyadenosylcobalamin-dependent methylmalonyl-CoA mutase (EC 5.4.99.2) was constantly found during growth of a strain of the root-nodule-forming bacterium Sinorhizobium meliloti harboring an extra plasmid-encoded copy of the methylmalonyl-CoA-mutase-encoding bhbA gene. The enzyme was purified to homogeneity and characterized. The purified enzyme was found to be a colorless apo-form. The apparent molecular weight of the enzyme was calculated to be 165,000±5,000 by Superdex 200 HR gel filtration. SDS-PAGE of the purified enzyme resolved one protein band with an apparent molecular mass of 80.0±2.0 kDa, indicating that the S. meliloti enzyme is composed of two identical subunits. The NH2-terminal sequence was identical to that predicted from the bhbA nucleotide sequence. Monovalent cations were required for enzyme activity.Abbreviations AdoCbl 5-Deoxyadenosylcobalamin - KPB Potassium phosphate buffer - MCM Methylmalonyl-CoA mutase - PVDF Polyvinylidene difluoride 相似文献
20.
Superoxide dismutase of anaerobic purple sulfur bacterium, Chromatium vinosum, was purified to a homogeneous state. The enzyme contains two atoms of iron per mole and has a molecular weight of 41,000. It is composed of two identical subunits. Amino acid composition, absorption spectra, and the reaction rate constant with O2? are also similar to those of the Fe-superoxide dismutases from aerobes. The enzyme is sensitive to hydrogen peroxide and methylene blue-sensitized photooxidation. The functional and evolutional aspects of superoxide dismutase in anaerobes are discussed. 相似文献