• BMB Reports
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• v.36 no.3
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• pp.282-287
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• 2003

The production of superoxide dismutase (SOD) varied in Deinococcus radiophilus, the UV resistant bacterium, depending upon different phases of growth, UV irradiation, and superoxide treatment. A gradual increase in total SOD activity occurred up to the stationary phases. The electrophoretic resolution of the SOD in cell extracts of D. radiophilus at each growth phase revealed the occurrence of MnSOD throughout the growth phases. The SOD profiles of D. radiophilus at the exponential phase received oxidative stress by the potassium superoxide treatment or UV irradiation also revealed the occurrence of a single SOD. However, these treatments caused an increase in SOD activity. The data strongly suggest that D. radiophilus has only one species of SOD as a constitutive enzyme, which seems to be a membrane-associated protein.

• Korean Journal of Microbiology
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• v.30 no.6
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• pp.483-487
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• 1992

Among a few number of UV-resistant isolated form various environmental sources (10), we made a comparative physio-chemoanalytical study on one of spherical bacteria isolated from air dust, presumably Deinococcus sp. (CM strain 29) with an UV resistant bacterium, Deinococcus radiophilus ATCC 27603 as the reference strain. Our isolate of UV resistant coccus, Deinococcus sp. CM 29 and D. radiophilus ATCC 27603 showed more than 75% matching coefficient in metabolic activity of various substrates. The most predominant cellular fatty acid of both strains was palmitoleic acid (C 16 :1, cis 9), but the detail fatty acid profiles were slightly dissimilar to each other. Cell-bound arange pigment seemed to be an identical chemicals on spectrophotometric analysis. L-ornithine was detected as cell-wall amino acid in both strains. Galactose was detected as cell-wall sugar in D. radiophilus ATCC 27603, whereas glucose in Deinococcus sp. CM 29. G-C molar ratio of both strains was comparable, 63-65%.

• 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.

• BMB Reports
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• v.31 no.2
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• pp.144-148
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• 1998

A bifunctional catalase-peroxidase, designated catalase-2, of a UV resistant Deinococcus radiophilus was purified to electrophoretic homogeneity by both chromatographic and electrophoretic methods. Its molecular weight was 310 kDa and composed of a tetramer of 80 kDa subunits. The catalase-2 exerted its optimal activity at $30^{\circ}C$ and around pH 9. Its $K_m$ value for $H_{2}0_{2} $ was about 10 mM. It showed the typical ferric heme spectrum with maximum absorption at 403 nm which shifted to 419 nm in the presence of cyanide. The ratio of A40i' A2S0 was 0.48. Fifty percent inhibition of the enzyme activity was observed at $4.6{\times}10^{-6}$, $7.7{\times}10^{-6}$, and $3.0{\times}10^{-6}$ M of NaCN, $NaN_3$, and $NH_{2}OH$, respectively. The enzyme was thermostable and not sensitive to 3-amino-1,2,4-triazole. Treatment of the enzyme with ethanol-chloroform caused a partial loss (30%) of its activity. The catalase-2 was distinct from the Deinococcal bifunctional catalase-3 in a number of properties, particularly in its molecular structure and substrate affinity.

• Journal of Microbiology
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• v.33 no.3
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• pp.239-243
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• 1995

Deinococcus radiophilus, an UV resistant bacterium seemed to contain three issoenzymes of catalase. Among them, the samllest and most abundant species in cell-free extract, catalase-3 which also exhibited peroxidase activity was purified to electrophoretic homogeneity (145-fold purification) by chromatographic procedures. Its molecular weight was 155 kDa composed of four 38 kDa subunits. The $K_{m}$ value of catalase-3 for H$\_$2/O$\_$2/ was approximately 0.5 mM. This enzyme showed a typical ferric heme spectrum with maximum absorption at 405 nm. Upon binding to cyanide, the 405 nm peak shifted to 420 nm. Catalase-3 was very sensitive to inhibitors of heme proteins, such as cyanide, azide and hydroxylamine. A ratio of A$\_$405/A$\_$28O/ was 0.5 Catalase-3 was active over a wide range of pH, between pH 7 and 10. The enzyme was rather heat-labile and partially sensitive to edthanol-chloroform treatment, but resistant to 3-amino-1, 2, 4-triazole. Catalase-3 of D. radiophilus, which is a bifunction catalatic peroxidatic enzyme seemed to share certain molecular properties with the typical catalase and the catalase-[roxidase along with its own unique features.

• Proceedings of the Microbiological Society of Korea Conference
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• 2001.11a
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• pp.61-73
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• 2001

• Proceedings of the Zoological Society Korea Conference
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• 1994.10a
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• pp.221.2-221
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• 1994

No Abstract, See Full Text

• BMB Reports
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• v.33 no.5
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• pp.412-416
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• 2000

The obligate aerobic Deinococcus are highly resistant against lethal effect of UV-and ionizing-radiation. Only five mesophilic Deinococcus species, i. e. D. radiodurans, D. radiophilus, D. proteolyticus, D. radiopugnans, and D. grandis are known. Since an indispensable role of catalase has been suggested in protecting cells against oxidative stress and UV radiation, Deinococcal catalase activity of each species and electrophoretic profiles of catalases were investigated on gel. Total catalase activity was varied among the species in the aerobically grown culture at stationary phase. The occurrence of multiple forms of catalases with different molecular weights in four species of Deinococcus and of a single catalase in D. radiopugnans suggests that each species shows the unique catalase profiles on gel. Some Deinococcal catalases also exhibit peroxidase activity. Since Deinococcus spp. are less-distinct to each other in their morphology, biochemical and physiological properties, the catalase profiles on PAGE would be useful in identifying the species of Deinococcus.

• Proceedings of the Zoological Society Korea Conference
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• 1996.10a
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• pp.208.2-208
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• 1996

No Abstract, See Full Text

• Journal of Microbiology
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• v.45 no.4
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• pp.318-325
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• 2007

Glucose 6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49) in Deinococcus radiophilus, an extraordinarily UV-resistant bacterium, was investigated to gain insight into its resistance as it was shown to be involved in a scavenging system of superoxide $(O_2^{-1})$ and peroxide $(O_2^{-2})$ generated by UV and oxidative stresses. D. radiophilus possesses two G6PDH isoforms: G6PDH-1 and G6PDH-2, both showing dual coenzyme specificity for NAD and NADP. Both enzymes were detected throughout the growth phase; however, the substantial increase in G6PDH-1 observed at stationary phase or as the results of external oxidative stress indicates that this enzyme is inducible under stressful environmental conditions. The G6PDH-1 and G6PDH-2 were purified 122- and 44-fold (using NADP as cofactor), respectively. The purified G6PDH-1 and G6PDH-2 had the specific activity of 2,890 and 1,033 U/mg protein (using NADP as cofactor) and 3,078 and 1,076 U/mg protein (using NAD as cofactor), respectively. The isoforms also evidenced distinct structures; G6PDH-1 was a tetramer of 35 kDa subunits, whereas G6PDH-2 was a dimer of 60kDa subunits. The pIs of G6PDH-1 and G6PDH-2 were 6.4 and 5.7, respectively. Both G6PDH-1 and G6PDH-2 were inhibited by both ATP and oleic acid, but G6PDH-1 was found to be more susceptible to oleic acid than G6PDH-2. The profound inhibition of both enzymes by ${\beta}-naphthoquinone-4-sulfonic$ acid suggests the involvement of lysine at their active sites. $Cu^{2+}$ was a potent inhibitor to G6PDH-2, but a lesser degree to G6PDH-1. Both G6PDH-1 and G6PDH-2 showed an optimum activity at pH 8.0 and $30^{\circ}C$.