• KSBB Journal
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• v.18 no.6
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• pp.517-521
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• 2003

Superoxide dismutase which is metalloenzyme that decomposes superoxide radicals into hydrogen peroxide and molecular oxygen. Vitreoscilla has FeSOD. Expression of FeSOD to paraquat was largely constitutive. This suggests that the basal level of FeSOD is sufficient to provide protection against superoxide generated during normal aerobic metabolism. Induction of SOD by iron supports that insertion of the active site metal into the corresponding apoprotein. The effect of paraquat on induction by iron seemed that iron brought the synergism effect in SOD activity with paraquat. It suggests that the relief of growth inhibition is due to protection against the lethality of O$_2$afforded by the elevated SOD. There may be control of FeSOD activity posttranslationally. Posttranslation control of enzyme function is particularly feasible for a metalloenzyme, for which conversion of apo- to holoenzyme may be the rate-limiting or regulatory step.

• Journal of Microbiology and Biotechnology
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• v.10 no.5
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• pp.700-706
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• 2000

Iron- and zinc-containing superoxide dismutase (FeZnSOD) and nickel-containing superoxide dismutase (NiSOD) are cytoplamic enzymes in Streptomyces griseus. The sodF gene coding for FeZnSOD was cloned from genomic Southern hybridization analysis with a 0.5-kb DNA probe, which was PCR-amplified with facing primers corresponding to the N-terminal amino acid of the purified FeZnSOD of S. griseus and a C-terminal region which is conserved among bacterial FeSODs and MnSODs. The sodF open reading frame (ORF) was comprised of 213 amino acid (22,430 Da), and the deduced sequence of the protein was highly homologous (86% identity) to that of FeZnSOD of Streptomyces coelicolor. The FeZnSOD expression of exponentially growing S. griseus cell was approximately doubled as the cell growth reached the early stationary phase. The growth-associated expression of FeZnSOD was mainly controlled at the transcriptional level, and the regulation was exerted through the 110 bp regulatory DNA upstream from the ATG initiation codon of the sodF gene.

• Korean Journal of Microbiology
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• v.52 no.2
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• pp.230-235
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• 2016

This study was carried out to analyze the differences in enzyme activity and stability between the native Fe superoxide dismutase (FeSOD) and the 6xHis-tagged superoxide dismutase (6xHis-FeSOD) of Streptomyces subrutilus P5. The optimum pHs for both native FeSOD and 6xHis-FeSOD were 7, while the pH range of the activity was narrower for the 6xHis-FeSOD. The native FeSOD was stable at pH 4-9, but the 6xHis-FeSOD lost its stability at pH > 9. The temperatures of the optimum activities were same for both types of enzymes. However, the heat stability of the 6xHis-FeSOD was clearly decreased; even at $20^{\circ}C$ the enzyme lost the activity after 360 min. In contrast, the native FeSOD was stable after 720 min at below $40^{\circ}C$. $H_2O_2$ inhibition was occurred already at 0.5 mM for the 6xHis-tagged enzyme. Therefore, from the results that the 6xHis-FeSOD retained the enzyme activity at pH 6-7 and $20-40^{\circ}C$, it can be assumed that the protein structure became destabilized under different storage conditions and sensitive to the enzyme inhibitor.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.6
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• pp.1020-1026
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• 1994

Pseudomonas plycolor was used to investigated the optimal culture condition to examine the various properties of superoxide dismutase (SOD). this SOD was inhibited by $H_2O_2$, azide ion, but not by cyanide ion. This result indicates that the enzyme might be a Fe-SOD. The composition of optimal culture medium for the enzyme production was 3% of glycerin, 1% of polypeptone, 0.5% of meat extract, 0.2% of KCI and the initial ph was 9.0 . The cultivation for the enzyme production was carried out in 500ml shaking flask containing 100ml of the optimal medium at $30^{\circ}C$ on a reciprocal shaker. The enzyme production reached maximum at 15hrs of cultivation and then declined sharply afterward.

• Korean Journal of Plant Resources
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• v.12 no.3
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• pp.234-239
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• 1999

The isoenzyme patterns and activities of superoxide dismutase(SOD) were investigated from leaves of Araliaceae plants. Of the eight isoenzymes, two isoenzymes(SOD 4 and SOD 6) were prevalent to leaves of Araliaceae plants. The patterns of these two isoenzymes were most various in the leaves of Acanthopanax senticosus for. inermis, while their activity was highest in the leaves of A. koreanum. These two isoenzymes were respectively identified as Fe-SOD and CuZn-SOD, based on selective inhibition with KCN or$H_2O_2$. The SOD isoenzyme patterns did not differed among stem barks, root barks and leaves of A. koreanum. However, the activities of Fe-SOD and CuZn-SOD were higher in the root bark and in leaves, respectively. Both of Fe-SOD and CuZn-SOD were stable for 1 hr at 30-4$0^{\circ}C$, while unstable above 5$0^{\circ}C$.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.4
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• pp.504-511
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• 1995

This study was conducted to investigate the superoxide dismutase (SOD) characteristics and antioxidant activity by nonenzymatic(Fe$^{2+}$/Ascorbate) and Fe$^{3+}$-ADP/NADPH method in perilla(Perilla frutescens var. japonica Hara.) and jaso(Perilla frutescens Briton var. acuta Kudo.) leaves. The characteristics were evaluated by the nitro blue tetrazolium reduction method. Perilla leaves contained three or four major SODs depending on the varieties. The inhibitor test indicated that the Perilla leaves contained two Cu /ZnSODs and one or two FeSODs, but Jaso leaves have only Cu/ZnSOD. However, no varietal differences were detected in the Cu /ZnSOD isozyme patterns. FeSODs, however, showed different varietal isozyme patterns through the different combinations of the two FeSOD isozymes. Among MeOH extractes, "mil yang 2" showed very strong antioxidant activity. Relatively large differences in the levels of SOD and antioxidant activity detected in the Perilla varietites. There was significantly different in the comparison between perilla leaves and red jaso leaves.s.etween perilla leaves and red jaso leaves.

• Journal of Microbiology and Biotechnology
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• v.14 no.4
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• pp.859-862
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• 2004

An isolate of Pseudomonas putida has been found to aggressively colonize root tips and induce plant resistance to Fusarium wilt. However, P. putida mutants lacking Fe-superoxide dismutase (SOD) or both FeSOD and MnSOD activities are less competitive in root tip colonization. In the current study, the growth of an FeSOD mutant was found to be more sensitive than that of the wild-type or a MnSOD mutant to oxidative stress imposed by paraquat treatment and culturing with the soil fungus Talaromyces flavus, which generates reactive oxygen species. Also, the loss of culturability with an aging stationary-phase culture was greater for a double SOD mutant than an FeSOD mutant, while no reduction in culturability was observed with the wild-type and a MnSOD mutant under the same protracted stationary-phase conditions. Accordingly, it was concluded that FeSOD activity is the major form of SOD in P. putida and plays an essential role in survival under stress conditions when increased oxidative stress is encountered.

• Journal of Microbiology
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• v.39 no.3
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• pp.232-235
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• 2001

Electrophoretic resolution of superoxide dismutase (SOD) from the highly UV-resistant bacteria, Deinococcus species revealed multiple forms of superoxide dismutases (SODs) in D. radiodurans, D. grandis, and D. proteolyticus, as judged from electrophoretic properties and metal cofactors. A single SOD occurred in both D. radiophilus and D. radiopugnans. Deinococcal SODs were either MnSOD, FeSOD or cambialistic Mn/FeSOD. The unique SOD profile of each mesophilic Deinococcus species, multiplicity and metal cofactors would be valuable in identifying Deinococcus species.

• Korean Journal of Microbiology
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• v.50 no.3
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• pp.179-184
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• 2014

Mitigation of heavy metal toxicity by iron containing superoxide dismutase (FeSOD) of Streptomyces subrutilus P5 was investigated. For E. coli $DH5{\alpha}$, the survival rate in the presence of 0.1 mM lead ions was only 7% after 120 min; however, with the addition of $0.1{\mu}M$ of purified native FeSOD the survival rate increased to 39%. This detoxification effect was also shown with 0.01 mM copper ions (survival increased from 6% to 50%), and the effect was stronger than with the use of EDTA. E. coli M15[pREP4] producing 6xHis-tagged FeSOD was constructed, and this showed an increase in survival rates throughout the incubation time; in the presence of 0.1 mM lead ions,the final increase at 60 min was from 3% to 19%. The FeSOD absorbed about 123 g-atom lead per subunit; therefore, we suggest that FeSOD could sequestrate toxic heavy metals to enhance bacterial survival against heavy metal contamination.

• Journal of Crop Science and Biotechnology
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• v.10 no.1
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• pp.8-12
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• 2007

All accessions of Rehmannia glutinosa show the unique characteristic of intrinsic tolerance to paraquat. The higher level of endogenous superoxide dismutase(SOD) activity and its increase upon paraquat treatment indicated the involvement of SOD in the tolerance mechanism to paraquat in R. glutinosa. In this study, we examined the isoform-specific response of SOD to oxidative stresses and hormones. Six SOD isoforms were found in the leaf, and they were identified as two MnSODs(named MnSOD I and MnSOD II, in order of increasing mobility), one FeSOD and three Cu/ZnSODs(named Cu/ZnSOD I, Cu/ZnSOD II, and Cu/ZnSOD III, in order of increasing mobility). MnSOD I, MnSOD II, FeSOD, Cu/ZnSOD I, Cu/ZnSOD II, and Cu/ZnSOD III, contributed to 4, 11, 7, 15, 30, and 32% of the total SOD activity, respectively. Total SOD activity levels in the leaf were increased by 4, 24, and 21% by paraquat, salicylic acid(SA), and yeast extract(YE), respectively, but little by ethephon. Six SOD isoforms responded differentially to these stresses and hormones. The activities of all the isoforms were increased by YE and SA except that of MnSOD I which was decreased by SA. The activities of MnSOD I, FeSOD, and CuZnSOD I were increased by paraquat. These results suggest that amelioration of oxidative stresses by SOD is fine-tuned by the differential expression of isoforms in R. glutinosa.