• Journal of Radiation Industry
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• v.8 no.2
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• pp.105-109
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• 2014

This study was conducted to investigate the sensitivity of Arthrobacter sp. PAMC 25486 to various mutagens. ${\gamma}-ray$, UV-ray, Ethyl methane sulfonate (EMS) and hydrogen peroxide ($H_2O_2$) were used as mutagen, and the survival rate of Arthrobacter sp. was measured at various doses of ${\gamma}-ray$ and UV-ray, and concentrations of EMS and $H_2O_2$. Decimal reduction dose ($D_{10}$ value) of Arthrobacter sp. was determined 370 Gy for a gamma irradiation treatment, 0.019 J for a UV ray, 2.5 mM for EMS, and 230 mM for $H_2O_2$. This result will be applied for the development of superior mutant strain of Arctic bacteria producing valuable compounds.

• The Korean Journal of Food And Nutrition
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• v.10 no.1
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• pp.117-121
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• 1997

The glucose isomerase productivity of Arthrobacter sp. L-3 was studied. glucose plus xylose showed higher productivity of glucose isomerase than any other carbon sources. Yeast extract showed higher productivity of glucose isomerase than any other nitrogen sources. The optimum culture time for the production of glucose isomerase was 40hrs.

• Microbiology and Biotechnology Letters
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• v.18 no.4
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• pp.360-367
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• 1990

The several glycoside hydrolysing enzymes related to rutin degradation are found to be rhamnosidase, glucosidase and rutinosidase. Rutinosidase was purified to electrophoretic homogeneity from cell extracts of rutin-degrading strain, MT-57, which was identified as a Arthrobacter sp. Its molecular weight was estimated to be 42, 000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and 40, 000 by gel filtration. The optimum pH for enzyme was found to be 7.5, and relatively stable in alkaline solution. The optimum temperature for enzyme was $45^{\circ}C$, being stable up to $50^{\circ}C$ for 20 min. The Bm value of enzyme for rutin was 0.5 $\mu \textrm m$. The enzyme activity was increased by the chelating agent such as EDTA, $NaN_3$, and 8-hydroxyquinoline, was strongly inhibited by $CO_{2+}, Ni^{2+}$, and $Cu^{2+}$. The enzyme had high substrate specificity in the rutinoside.

• Korean Journal of Environmental Agriculture
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• v.34 no.2
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• pp.139-148
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• 2015

BACKGROUND: The aim of this study was to isolate and identify algicidal bacterium that tends to kill the toxic dinoflagellate Alexandrium catenella, and to determine the algicidal activity and algicidal range of algicide. METHODS AND RESULTS: Among of algicidal bacteria isolated in this study, NH-3 isolate was the strongest algicidal activity against A. catenella. NH-3 isolate was identified on the basis of biochemical characteristics and analysis of 16S rRNA gene sequences. The NH-3 isolate showed over 99% homology with Arthrobacter oxydans, and was designated as Arthrobacter sp. NH-3. The optimal culture conditions were $25^{\circ}C$, initial pH 7.0, and 2.0% (w/v) NaCl concentration. The algicidal activity of Arthrobacter sp. NH-3 was significantly increased to maximum value in the late of logarithmic phase. Arthrobacter sp. NH-3 showed algicidal activity through indirect attack, which excreted active substance into the culture filtrate. When 10% culture filtrate of NH-3 was applied to A. catenella, 100% of algal cells were destroyed within 30 h. In addition, the algicidal activities were increased in dose and time dependent manners. The pure algicide was isolated from the ethyl acetate extract of the culture filtrate of NH-3 by using silica gel column chromatography and high performance liquid chromatography (HPLC). We investigated the algicidal activity of this algicide on the growth of harmful algal bloom (HAB) species, including A. catenella. As a result, it showed algicidal activity against several HAB species at a concentration of $100{\mu}g/mL$ and had a relatively wide host range. CONCLUSION: Taken together, our results suggest that Arthrobacter sp. NH-3 and its algicide could be a candidate for controlling of toxic and harmful algal blooms.

• Microbiology and Biotechnology Letters
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• v.23 no.1
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• pp.68-74
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• 1995

A bacterial strain A-6 producing the high level of an extracellular inulin fructotransfe rase(depolymerizing)(EC 2.4.1.93) which converts inulin into di-D-fructofuranose dianhydride III (DFAIII) was isolated from soil. The isolated strain could be classified as a species belonging to the genus Arthrobacter based on its morphological and physiological characteristics identified in this work. Production of the enzyme was induced by inulin, and the highest activity was detected in the slightly acidic medium supplemented with 2.5% inulin and 0.1% trypton as a sole carbon and a nitrogen source, respectively. Under the optimal conditions, the enzyme activity in the culture supernatant reached approximately 60 uints/ml after 96 hours of cultivation. The optimum pH and temperature for the crude enzyme preparation from Arthrobacter sp. A-6 were pH 5.0 and 60$\circ$C , respectively. The DFA produced by the action of the inulin fructotransferase was confirmed to be DFAIII by paper chromatography, HPLC and $^{13}$C-NMR spectroscopy.

• Korean Journal of Environmental Agriculture
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• v.34 no.3
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• pp.244-251
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• 2015

BACKGROUND: Recent studies have described the importance of bacteria that can degrade polycyclic aromatic hydrocarbons (PAHs). Here we screened bacterial isolates from commercial gasoline for PAH degraders and characterized their ability to degrade PAHs, lipids and proteins as well as their enantioselective epoxide hydrolase activity, salt tolerance, and seawater survival. METHODS AND RESULTS: One hundred two bacteria isolates from commercial gasoline were screened for PAH degraders by adding selected PAHs on to the surface of agar plates by the sublimation method. A clear zone was found only around the colonies of PAH degraders, which accounted for 13 isolates. These were identified as belonging to Bacillus sp., Brevibacterium sp., Micrococcus sp., Corynebacterium sp., Arthrobacter sp., and Gordonia sp. based on 16S rRNA sequences. Six isolates belonging to Corynebacterium sp., 3 of Micrococcus sp., Arthrobacter sp. S49, and Gordonia sp. H37 were lipid degraders. Arthrobacter sp. S49 was the only isolate showing high proteolytic activity. Among the PAH-degrading bacteria, Arthrobacter sp. S49, Brevibacterium sp. S47, Corynebacterium sp. SK20, and Gordonia sp. H37 showed enantioselective epoxide hydrolase activity with biocatalytic resolution of racemic styrene oxide. Among these, highest enantioselective hydrolysis activity was seen in Gordonia sp. H37. An intrinsic resistance to kanamycin was observed in most of the isolates and Corynebacterium sp. SK20 showed resistance to additional antibiotics such as tetracycline, ampicillin, and penicillin. CONCLUSION: Of the 13 PAH-degraders isolated from commercial gasoline, Arthrobacter sp. S49 showed the highest lipid and protein degrading activity along with high active epoxide hydrolase activity, which was the highest in Gordonia sp. H37. Our results suggest that bacteria from commercial gasoline may have the potential to degrade PAHs, lipids, and proteins, and may possess enantioselective epoxide hydrolase activity, high salt tolerance, and growth potential in seawater.

• Journal of Microbiology and Biotechnology
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• v.6 no.6
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• pp.402-406
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• 1996

Inulin fructotransferase (depolymerizing) (EC 2.4.1.93) was purified 34-fold from the culture broth of Arthrobacter sp. A-6 by using a combination of ammonium sulfate fractionation, DEAE-Sepharose CL-6B chromatography and Sephacryl S-200 gel filtration. The purified enzyme converts inulin into di-D-fructofuranose dianhydride III(DFA III) and small quantities of fructo-oligosaccharides. The temperature and pH optima of the enzyme were $70^{\circ}C$ and 6.0, respectively. Molecular weight of the enzyme was determined to be 49 kDa by 12$%$ SDS-polyacrylamide gel electrophoresis, and 145 kDa by Sephacryl S-200gel filtration. This indicates that the functional inulin fructotransferase of Arthrobacter sp. A-6 has a homomeric trimer structure. The enzyme had an isoelectric point of pH 4.6. The N-terminal amino acid sequence of the purified enzyme subunit was Ala-Asp-Asn-Pro-Asp-Gly(\ulcorner)-Ser-Asn-Met(or Glu)-Tyr-Asp-Val.

• Journal of the Korean Applied Science and Technology
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• v.39 no.6
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• pp.831-838
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• 2022

An auxin-producing bacteria, KSD16, KSD33, and KSD36 were isolated from agricultural soil. The strain KSD16, KSD33, and KSD36 was classified as a strain of Arthrobacter sp. based on phylogenetic analysis of 16S rRNA gene. The isolated KDS16, KDS33, and KSD36 was confirmed to produce indole-3-acetic acid (IAA), which is one of the auxin hormones. When the concentration of IAA was assessed the maximum concentration of IAA, 206.62 mg L^-1, was detected from the culture broth incubated in R2A medium containing 0.1% L-tryptophan for 48 h at 28 ℃. To study the effect of IAA producing bacteria on germination rate, seeds of Mung bean were prepared for each treatment. KSD16, KSD33, and KSD36 showed significant increase in root length and number of adventitious roots than the controls. To investigate the growth-promoting effects on the crops, Arthrobacter species were placed in water cultures and seed pots of mung beans. In consequence, the seed germination of mung beans was 73.4% higher than the control.

• Korean Journal of Microbiology
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• v.50 no.1
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• pp.67-72
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• 2014

Minimal broth containing nicotine as a sole carbon source (MB/N) was used to isolate novel nicotine-degrading bacterial strains from tobacco plants and field soils. Comparative analysis of 16S rRNA gene sequence, phenotypic test and morphological tests showed that the position of these isolates were in the genus Arthrobacter of the family Micrococcaceae. The highest 16S rRNA gene sequence similarity of the isolate NU11 and NU15 to type strains in the genus Arthrobacter were Arthrobacter equi (98.2%) which was presumably a novel strain and Arthrobacter nicotinovorans (99.8%), respectively. Both strain NU11 and NU15 showed rod shaped, Gram-positive characteristics and catalase activity, but did not show oxidase activity. The novel strain NU11 was found to degrade efficiently nicotine in MB/N medium by the analysis of UV absorption spectra and could be used as an organism in bioremediation technique.

• Korean Chemical Engineering Research
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• v.54 no.1
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• pp.140-144
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• 2016

In this study, the physical factors for amylase production by Arthrobacter sp. were optimized using response surface methodology(RSM). Antarctic microorganism Arthrobacter sp. PAMC 27388 was obtained from the Polar and Alpine Microbial Collection(PAMC) at the Korea Polar Research Institute. This microorganism was confirmed for the excretion of amylase with Lugol's solution. The amylase activity was after flask culture was as low as 1.66 mU/L before optimization. The physical factors including the inoculum volume, the initial culture pH, and the medium volume were chosen to be optimized for the enhanced amylase production. The calculated results using RSM indicate that the optimal physical factors were 2.49 mL inoculum volume, 6.85 pH and 42.87 mL medium volume with a predicted amylase production of 2.84 mU/L. The experimentally obtained amylase activity was 2.50 mU/L, which was a 150% increase compared to the level before optimization.