• Microbiology and Biotechnology Letters
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• v.40 no.4
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• pp.419-423
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• 2012

A xylanolytic bacterial strain, MX47, was isolated from rotting plant matter in soil. The strain was aerobic and gram positive, and grew between pH 6.0 and 11.0. Cells were susceptible to thiostrepton and chloramphenicol. The major fatty acids (>3%) comprised 64.55% of iso-$C_{15:0}$, 22.76% of anteiso-$C_{15:0}$, and 3.92% of iso-$C_{17:0}$. The G/C content of the DNA was 44.15 mol%. The predominant respiratory quinone was menaquinone 7 (MK-7). Searches for 16S rRNA gene sequence similarity as well as phylogenetic analyses strongly suggested that the strain should be classified to the genus Bacillus. However, its biochemical characteristics, including acid production and enzyme activities, are different from those of other Bacillus strains in the same clade, and therefore, we propose the name Bacillus sp. MX47.

• Korean Journal of Veterinary Research
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• v.57 no.3
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• pp.201-204
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• 2017

A Gram-negative, catalase- and oxidase-positive, coccus-shaped bacterium was isolated from a rabbit with keratoconjunctivitis. Colonies of the isolate were round, smooth, and exhibited hemolytic activity on 5% sheep blood agar. Scanning electron microscopy revealed 0.4 to $0.5{\mu}m$ diameter oval cocci. Partial 16S rRNA gene (1446 bp) sequence analysis demonstrated the isolate had significant homology with the Moraxella cuniculi CCUG2154 strain isolated from a rabbit in Germany in 1973. Our isolate was designated as APQAB1701. Antibiotic susceptibility tests demonstrated that APQAB1701 was sensitive to 24 antibiotics; 3 of the antibiotics (nalidixic acid, spectinomycin, and colistin) had minimal inhibitory concentrations ${\geq}32{\mu}g/mL$ against the isolate.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.3
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• pp.826-828
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• 2003

The effects of crude extract and bioactive fractions from Brachyglottis monroi on biological activity were investigated. The crude ethanol extract inhibited the growth of the Gram positive bacterium Bacillus subtilis (ATCC Strain number 19659, 1 mm zone at 150 μg/disk) and the dermatophyte Trichophyton mentagrophytes (ATCC 28185, 2 mm zone at 150 μg/disk), and toxic to P388 tumor cells (IC50 23.96 μg/ml at 75 μg/disk). Cytotoxic activity was strongly showed by Fr. 6 (P388 IC50 19.67 μg/ml at 75 μg/disk).

• Journal of Microbiology and Biotechnology
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• v.11 no.5
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• pp.756-762
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• 2001

As a component for a recirculating aquaculture system, a new strain of denitrifying bacterium was isolated from municipal sewage. The isolate was motile by means of one polar flagellum, catalase-positive, and a Gram-negative rod-shaped cell measuring $0.5-0.6{\mu}m$ in width and $1.3-1.9{\mu}m$ in length. The isolate was identified as Pseudomonas fluorescens and produced dinitrogen gas via the reduction of nitrate. The optimal growth conditions (pH, temperature, carbon source, and C/N ratio) of the isolate were found to be 6.8, $30^{\circ}C$, malate, and 3, respectively. Under optimal growth conditions of P. fluorescens, dinitrogen gas was first detected in the exponential growth phase, then a small amount of nitrite was developed and converted to dinitrogen gas in the stationary phase. Pseudomonas fluorescens cells were immobilized in modified polyvinyl alcohol (PVA) gel beads, and the maximum denitrification rate was measured as $36.6 {\mu}lN_2h^-1$ per bead with an optimum cell loading of $20mg {\mu}l^-1$ and $2\%$ sodium alginate added to the PVA gel. The operating stability of the modified PVA gel beads remained unchanged for up to 43 repeated batches.

• Journal of Microbiology and Biotechnology
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• v.9 no.5
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• pp.646-649
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• 1999

A thermophilic bacterium producing D-stereospecific dipeptidase was isolated from Korean soil samples. The enzyme hydrolyzed the peptide bond between D-alanyl-D-alanine (D-Ala-D-Ala). The isolated bacterial strain was rod shaped, gram-positive, motile, and formed an endospore. Morphological and physiological characteristics suggested this microorganism a thermophilic Bacillus species, and was named as Bacillus sp. BCS-l. The production of D-stereospecific dipeptidase was growth-associated and optimal at $55^{\circ}C$. The enzyme was applied for the synthesis of D-amino acid-containing peptide, N-benzyloxycarbonyl-L-aspartyl-D-alanine benzyl ester (Z-L-Asp-D-AlaOBzl), as a model reaction. A thermodynamically controlled synthesis of Z-L-Asp-D-AlaOBzl was achieved in an organic solvent.

• Journal of Microbiology and Biotechnology
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• v.22 no.4
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• pp.541-546
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• 2012

The biodegradation of phenol in laboratory-contaminated soil was investigated using the Gram-positive soil bacterium Corynebacterium glutamicum. This study showed that the phenol degradation caused by C. glutamicum was greatly enhanced by the addition of 1% yeast extract. From the toxicity test using Daphnia magna, the soil did not exhibit any hazardous effects after the phenol was removed using C. glutamicum. Additionally, the treatment of the phenol-contaminated soils with C. glutamicum increased various soil amino acid compositions, such as glycine, threonine, isoleucine, alanine, valine, leucine, tyrosine, and phenylalanine. This phenomenon induced an increase in the seed germination rate and the root elongation of Avena sativa (oat). This probably reflects that increased soil amino acid composition due to C. glutamicum treatment strengthens the plant roots. Therefore, the phenol-contaminated soil was effectively converted through increased soil amino acid composition, and additionally, the phenol in the soil environment was biodegraded by C. glutamicum.

• Journal of Microbiology and Biotechnology
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• v.14 no.2
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• pp.312-316
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• 2004

Five strains, producing bacterial thermostable L-arabinose isomerase, were isolated from Korean soil samples obtained from compost under high temperature circumstances. Among these strains, the CBG-Al showed the highest L-arabinose isomerase activity at $60^\circ{C}$ and was selected as a D-tagatose producing strain from D-galactose. This strain was identified as Geobacillus thermodenitrificans based on the 16S rRNA analysis, and biological and biochemical characteristics. The isolated strain was aerobic, rod-shaped, Gram-positive, nonmotile, and an endospore-forming bacterium. No growth was detected in culture temperature below $40^\circ{C}$. The maximum growth temperature and maximum temperature of enzyme activity were $75^\circ{C}$ and $65^\circ{C}$, respectively. In metal ion effects, $Ca^{2+}$ was the most effective enzyme activator with the reaction rate by 150%. In a 5-1 jar fermentor with 3-1 MY medium, L-arabinose isomerase activity was growth-associated and pH decreased rapidly after the initial logarithmic phase.

• Microbiology and Biotechnology Letters
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• v.32 no.4
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• pp.362-365
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• 2004

The fucoidan from Laminaria relicollected at Wando in Korea was purified with the yield of 2.3% in mass. The monosaccharide composiof the purified fucoidan was nearly identical to that of the commercial standard: fucose 63.71 %, xylose 22.98%, galactose 6.62%, mannose 0.24%, and uronic acid 3.26%. Microorganisms capable of degrading the purified fucoidan were isolated from the colonies on the minimal medium containing 0.2% of purified fucoidan as a sole carbon source. Of these isolates, a strain showing a relatively higher capability to degrade fucoidan, up to 63%, was partially characterized as a Gram positive, aerobic, moderately halophilic marine bacterium.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.1
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• pp.250-253
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• 2004

The effects of crude extracts from medicinal plants on biological activity were investigated. The crude ethanol extract of H. paucistipula inhibited the growth of the Gram positive bacterium Bacillus subtilis ATCC 19659, (2 mm inhibition zone at 150 ㎍/disc) and the dermatophyte Trichophyton mentagrophytes ATCC 28185, (7 mm inhibition zone at 150 ㎍/disc), and toxic to P388 murine leukaemia cells ATCC CCL 46 P388D1, (IC/sub 50/ 2.48 ㎍/㎖ at 75 ㎍/disc). This crude ethanol extract of H. paucistipula is the strongest antimicrobial and cytotoxic activities against P388 murine leukaemia cells ATCC CCL 46 P388D1.

• Journal of Microbiology and Biotechnology
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• v.22 no.5
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• pp.684-689
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• 2012

In the present study, an efficient mercury-tolerant bacterial strain (RS-5) was isolated from heavy-metalcontaminated industrial effluent. Under shake flask conditions, 97% of the supplemented mercuric chloride was sequestered by the biomass of RS-5 grown in a tryptone soy broth. The sequestered mercuric ions were transformed inside the bacterial cells, as an XRD analysis of the biomass confirmed the formation of mercurous chloride, which is only feasible following the reaction of the elemental mercury and the residual mercuric chloride present within the cells. Besides the sequestration and intracellular transformation, a significant fraction of the mercury (63%) was also volatilized. The 16S rRNA gene sequence of RS-5 revealed its phylogenetic relationship with the family Bacillaceae, and a 98% homology with Lysinibacillus fusiformis, a Gram-positive bacterium with swollen sporangia. This is the first observation of the sequestration and volatilization of mercuric ions by Lysinibacillus sp.