• Microbiology and Biotechnology Letters
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• v.9 no.2
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• pp.91-97
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• 1981

A thermophilic soil isolate Bacillus sp. Y-127 was selected for the production of thermostable amylase. The strain was used for the enzyme production and the thermostable amylase was characterized. The optimum cultural conditions for the enzyme production were 6$0^{\circ}C$ at pH 7.0 for 32 hours using a mineral medium containing 2% soluble starch and 0.2% yeast extract. The extra-cellular enzyme was purified about 123-folds with about 6% recovery. The purified enzyme was stable at pH between 4.0 and 7.0, and temperature up to 6$0^{\circ}C$.

• Microbiology and Biotechnology Letters
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• v.29 no.3
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• pp.134-141
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• 2001

A bacterial strain KP-364 producing extracellular keratinolytic protease was isolated from the soil of the poultry fac-tory. It was identified as Pseudomonas sp. based on its morphological and physiological characteristics, The optimal culture conditions for the production of keratinolytic protease by Pseudomonas sp. KP-364 were investigated. The composition of optimal medium for the keratinolytic protease was 2.0% glucose, 0.5% soybean meal. 0.5% $NaNO_3$ and 0.2% KCI Optimal initial pH for production of Keratinolytic protease production were 6.5 and $37^{\circ}C$ respec- tively. The keratinolytic protease production reached a maximum of 1,270 U/ml/hr after 48 hours cultivation under the optimal culture conditions.

• Korean Journal of Environmental Biology
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• v.22 no.4
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• pp.487-493
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• 2004

To investigate the antifungal activity related protein in pesticidal bacteria, a bacterial strain LTD was isolated from soil collected at Gimje in Jeonbuk province, Korea, and identified as Bacillus subtilis LTD based on a API50 CHB kit and 168 rDNA sequencing. It has an antifungal activity against 9 plant pathogenic fungi in a paper disc assay. The antifungal activity- deficient mutant, B. subtilis mLTD was induced at a 5 kGy dose of $^{60}Co$ gamma radiation. Using the two-dimensional electrophoresis and the matrix assisted laser desorption ionization time-of-flight mass spectrometry, the comparison analysis of proteins between the wild and mutant were performed. A major intracellular serine proteinase IspA (MW: 32.5 kDa), a NAD (P) H dehydrogenase (MW: 20.0 kDa), and a stage II sporulation protein AA, SpoIIAA (MW: 14.3kDa) were detected only in the B. subtilis LTD. These results suggested that the functions of these proteins found only in the B. subtilis LTD could. be closely related to the antifungal activity against plant pathogenic fungi.

• Journal of Microbiology and Biotechnology
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• v.14 no.5
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• pp.938-943
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• 2004

A gene responsible for the chlorothalonil-biotransformation was cloned from the chromosomal DNA of Ochrobactrum anthropi SH35B, an isolated bacterium strain from soil. We determined the nucleotide sequences and found an open reading frame for glutathione S-transferase (GST). The drug-hypersensitive Escherichia coli KAM3 cells transformed with a plasmid carrying the GST gene can grow in the presence of chlorothalonil. The GST of O. anthropi SH35B was expressed in E. coli and purified by affinity chromatography. The fungicide chlorothalonil was rapidly transformed by the purified GST in the presence of glutathione. No significant difference in the chlorothalonil-biotransformation effect was observed among the thiol compounds (cysteine, reduced glutathione, and $\beta$-mercaptoethanol). Thus, the result reported here is the first evidence on the chlorothalonil-biotransformation by conjugation with the cellular free thiol groups, especially glutathione, catalyzed by the bacterial GST.

• Microbiology and Biotechnology Letters
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• v.8 no.1
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• pp.27-32
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• 1980

We isolated a strain of Pseudomonas sp. from soil to utilize furfuryl alcohol as a carton source by enrichment culture. Alcohol dehydrogenase from this bacteria was purified 700-fold by Sephadex G-200 and affinity column chromatography to be homogeneous by electrophoresis and analytical centrifugation. This enzyme had a molecular weight of 120,000 and was composed of four subunits consisting of 266 amino acid residues. The optimal pH of the enzyme was pH 8.5 to 9, and the optimal temperature was, 45$^{\circ}C$. This enzyme was stable at 55$^{\circ}C$, but lost 80% of its activity in 10min at 6$0^{\circ}C$.

• Journal of Microbiology and Biotechnology
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• v.19 no.5
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• pp.474-481
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• 2009

A novel microorganism, designated as LG12, was isolated from soil based on its ability to use acrylic acid as the sole carbon source. An electron microscopic analysis of its morphological characteristics and phylogenetic classification by 16S rRNA homology showed that the LG12 strain belongs to Rhodococcus erythropolis. R. erythropolis LG12 was able to metabolize a high concentration of acrylic acid (up to 40 g/l). In addition, R. erythropolis LG12 exhibited the highest acrylic acid-degrading activity among the tested microorganisms, including R. rhodochrous, R. equi, R. rubber, Candida rugosa, and Bacillus cereus. The effect of the culture conditions of R. erythropo/is LG12 on the production of 3-hydroxypropionic acid (3HP) from acrylic acid was also examined. To enhance the production of 3HP, acrylic acid-assimilating activity was induced by adding 1 mM acrylic acid to the culture medium when the cell density reached an $OD_{600}$ of 5. Further cultivation of R. erythropo/is LG 12 with 40 g/l of acrylic acid resulted in the production of 17.5 g/l of 3HP with a molar conversion yield of 44% and productivity of 0.22 g/l/h at $30^{\circ}C$ after 72 h.

• Journal of Microbiology and Biotechnology
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• v.19 no.8
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• pp.836-844
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• 2009

A denitrification bacterium was isolated from riverbed soil and identified as Ochrobactrum sp., whose specific enzymes for denitrification metabolism were biochemically assayed or confirmed with specific coding genes. The denitrification activity of strain G3-1 was proportional to glucose/nitrate balance, which was consistent with the theoretical balance (0.5). The modified graphite felt cathode with neutral red, which functions as a solid electron mediator, enhanced the electron transfer from electrode to bacterial cell. The porous carbon anode was coated with a ceramic membrane and cellulose acetate film in order to permit the penetration of water molecules from the catholyte to the outside through anode, which functions as an air anode. A non-compartmented electrochemical bioreactor (NCEB) comprised of a solid electron mediator and an air anode was employed for cultivation of G3-1 cells. The intact G3-1 cells were immobilized in the solid electron mediator, by which denitrification activity was greatly increased at the lower glucose/nitrate balance than the theoretical balance (0.5). Metabolic stability of the intact G3-1 cells immobilized in the solid electron mediator was extended to 20 days, even at a glucose/nitrate balance of 0.1.

• Applied Biological Chemistry
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• v.30 no.1
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• pp.40-45
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• 1987

Degradation of polychlorinated biphenyls(PCBs) and organochlorine pesticides by Alcaligenes aquamarinus has been studied and also degradation product of PCB-42 was investigated by TLC and GC. The less chlorinated members of PCBs such as Aroclor 1016 was degraded readily by the strain and rates of the microbial degradation of several organochlorine pesticides were found to decrease in the order of p,p'-DDT, r-BHC and Thiolix. Approximately 40 percent of PCB-42 was degraded when incubated with non-autoclaved soil for 25 days at $25^{\circ}C$. The yellow compound from PCB-42 was tentatively identified as p-chlorobenzoic acid.

• Microbiology and Biotechnology Letters
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• v.29 no.1
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• pp.43-49
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• 2001

Indole and its derivatives form a class of toxic recalcitrant environmental pollutants, Abacte-rium, strain KL-9 was isolated from soil with indole as a sole source of carbon and nitrogen. KL-9 was identified as Acinetobacter sp. on the basis of 16 S rRNA gene sequence, fatty acid and quinone compositions. This identification was also confirmed by the ability of carbon source utilization and other biochemical tests. The growth of Acinetobacter sp. KL-9 was fastest with 0.3mg/ml of indole as was inhibited by higher than 0.5mg/ml of indole in the medium, KL-9 with indole also produced indigo. The formation of indigo was stimulated inthe presence of glucose, which is not a growth-suppoting carbon source for KL-9. Additional biotransformation evidence showed that anthranilate is an intermediate for the degradation of indole KL-9.

• Journal of Microbiology and Biotechnology
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• v.11 no.2
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• pp.242-250
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• 2001

A Gram-positive bacterium (strain JB-13) that was isolated from soil as a producer of cyclodextrin glucanotransferase (CGTase) [EC 2.4.1.19] was identified as Panibacillus sp. JB-13. This CGTase could catalyze the transglucosylation reaction from soluble starch to L-ascorbic acid (AA). A main product formed by this enzyme with ${\alpha}-glucosidase$ was identified as $2-O-{\alpha}-D-glucopyranosyl{\;}_{L}-ascorbic$ acid (AA-2G) by the HPLC profile and the elemental analysis. CGTase was purified to homogeneity using ammonium sulfate fractionation, ion-exchange chromatography on DEAE-Seohadex A-50, and gel chromatography on Sephacryl S-200HR. The molecular weight was determined to be 66,000 by both gel chromatography and SDS-PAGE. The isoelectric point of the purified enzyme was 5.3. The optimum pH and temperature was PH 7.0 and $45^{\circ}C$ respectively. The enzyme was stable in the range of pH 6-9 and at temperatures of $75{\circ}C$ or less in the presence of 15 mM ${CaCl_2}.\;{Hg^2+},\;{Mn^+2},{Ag^+},\;and\;{Cu^2+}$ all strongly inhibited the enzyme's activity.