• Journal of Microbiology and Biotechnology
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• 제5권4호
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• pp.206-212
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• 1995

A strain BL-29, which produces a extracellular lytic enzyme on E. coli was isolated from the soil. The strain was identified as belonging to the genus Bacillus sp. The lytic enzyme was purified to homogeneity by ion exchange chromatography and gel filtration. Specific activity of the purified enzyme was 28, 850 U/mg protein and yield of the enzyme was 5$%$. The purified enzyme showed a single band on SDS-PAGE and its molecular weight was estimated to be 31, 000 by SDS-polyacrylamide gel electrophoresis and gel filtration column chromatography. The optimum temperature and pH were $55^{\circ}C$ and pH 10.0, respectively. The enzyme was stable at $45^{\circ}C$ but enzyme activity was reduced by up to 50$%$ when the temperature was raised to $55^{\circ}C$ for 15 min. Stable range of pH was from 5.0 to 11.0. but Enzyme activity was inhibited by lead-acetate, mercuric chloride, ethylene glycol-bis-[$\beta$-aminoethyl ether]-N, N, $N^1, $N^1$-tetraacetic acid (EGTA), and ethylenediamine tetraacetic acid (EDTA), but not affected considerably by treatment with other chemical reagents.

• 한국토양비료학회지
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• 제44권5호
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• pp.801-807
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• 2011

유기물 연용이 감자재배 토양의 토양화학성과 효소활성에 미치는 영향을 평가하고자 비화산 암갈색 토양에서 1년 2기작으로 3 작기 동안 감자재배를 하였다. 유기물은 작기당 유기질비료와 음식물퇴비는 $2,000kg\;10a^{-1}$, 돈분퇴비는 2,000, 4,000, and $6,000kg\;10a^{-1}$을 기준으로 시용하였다. 토양 pH는 3 작기 후 모든 처리구에서 높았다. PMC 시용량이 많을수록 토양 pH, 토양질소, 유효인산, 치환성 양이온 (칼륨, 칼슘 및 마그네슘), Zn, Cu 함량이 증가하였다. 토양 탈수소효소활성은 PMC 시용량이 많고 작기가 증가할수록 대조구 보다 3작기 후는 PMC 4톤구가 2배 이상 높았으며, PMC>FWC>NPK+PMC>MOF 순으로 증가하였다. 토양인산효소활성은 PMC 6톤구에서 가장 높았다. 3작기 동안 유기물 처리구의 Zn함량이 증가함에 따라 탈수소효소 활성이 직선적으로 증가하였으며 MOF구 $R^2$=0.427, FWC 구 $R^2$=0.427, PMC구 $R^2$=0.411 (p<0.01)의 상관관계를 나타냈다.

• The Korean Journal of Ecology
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• 제9권4호
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• pp.231-241
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• 1986

The annual decomposition of cellulose and hemicellulose by microorganism and distribution of soil microbial flora were investigated in the humus horizon of a Pinus rigida stand in Mt. Kwanak. The cellulase activity was the lowest, 142$\mu$g glucose/g/hr from Dec. 1985 to Mar. 1986 and the highest, 760~1, 072$\mu$g glucose/g/hr in Jul. and Aug. 1985. The xylanase activity was 47% higher than the cellulase activity and was the lowest, 211~275$\mu$g xylose /g/hr from Feb. to Mar. 1986 and the highest as 799~1, 322$\mu$g xylose/g/hr from Jun. to Aug. 1986. The vertical distribution of the enzyme activity was decreased with the order of F, H, L, and A1 in both enzymes and the activities were exponentially decreased below L horizon, which suggests that most decomposition be done in F and H horizons with lots of organic matters. The SEM study slowed that the main decomposers of litters were fungi and initial attack into litters was also made by them. The enzyme activities of soil had strong correlations with the temperature and the precipitation. The correlation coefficients were 0.813 and 0.886 in the cellulase, and 0.673 and 0.626 in the xylanase for the temperature and the precipitation, respectively.

• Journal of Applied Biological Chemistry
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• 제60권3호
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• pp.257-263
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• 2017

A cellulolytic strain Y2 was isolated from soil obtained in the Canadian Alpine region. The isolate was identified as Paenibacillus sp. Y2 by 16S rRNA sequencing. When grown in LB medium supplemented with carboxymethyl-cellulose (CMC), CMCase production increased to 122.0% of that observed in LB without CMC. Culture supernatant was concentrated by ultrafiltration and 80% ammonium sulfate precipitates were separated by Hi-Trap Q and CHT-II chromatography. The purified enzyme (EG-PY2) showed a homogeneous single band and the molecular mass was estimated to be 38 kDa by SDS-PAGE. Optimum pH and temperature of the enzyme were 4.5 and $30^{\circ}C$, respectively. The half-life of enzyme activity at 50 was 140.7 min, but the enzyme was drastically inactivated within 5 min at $55^{\circ}C$. The enzyme was highly activated to 135.7 and 126.7% by 5.0 mM of $Cu^{2+}$ or $Mg^{2+}$ ions, respectively, and moderately activated by $Ba^{2+}$ and $Ca^{2+}$ ions, whereas it was inhibited to 76.8% by $Fe^{2+}$, and to ${\leq}50%$ by $Mn^{2+}$, $Co^{2+}$, $Zn^{2+}$, and EDTA. The enzyme was activated to 211.5% in the presence of 0.5 M of NaCl and greatly tolerant to 3.15M of NaCl. The enzyme showed 2.98 times higher ${\beta}$-glucanase activity than CMCase activity. Based on these results, it can be concluded that EG-PY2 is an acidophilic, cold-active, and halotolerant endoglucanase. The authors suggest it is considered to be useful for various industrial applications, such as, fruit juice clarification, acidic deinking processes, high-salt food processing, textile and pulp industries, and for biofuel production from seaweeds.

• Journal of Microbiology
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• 제42권4호
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• pp.267-277
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• 2004

Effects of elevated $CO_2$ on soil microorganisms are known to be mediated by various interactions with plants, for which such effects are relatively poorly documented. In this review, we summarize and syn­thesize results from studies assessing impacts of elevated $CO_2$ on soil ecosystems, focusing primarily on plants and a variety the of microbial processes. The processes considered include changes in microbial biomass of C and N, microbial number, respiration rates, organic matter decomposition, soil enzyme activities, microbial community composition, and functional groups of bacteria mediating trace gas emission such as methane and nitrous oxide. Elevated $CO_2$ in atmosphere may enhance certain micro­bial processes such as $CH_4$ emission from wetlands due to enhanced carbon supply from plants. How­ever, responses of extracellular enzyme activities and microbial community structure are still controversy, because interferences with other factors such as the types of plants, nutrient availabilitial in soil, soil types, analysis methods, and types of $CO_2$ fumigation systems are not fully understood.

• Journal of Microbiology and Biotechnology
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• 제24권1호
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• pp.80-86
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• 2014

Tannase (Tan410) from a soil metagenomic library was immobilized on different supports, including mesoporous silica SBA-15, chitosan, calcium alginate, and amberlite IRC 50. Entrapment in calcium alginate beads was comparatively found to be the best method and was further characterized. The optimum pH of the immobilized Tan410 was shifted toward neutrality compared with the free enzyme (from pH 6.4 to pH 7.0). The optimum temperature was determined to be $45^{\circ}C$ for the immobilized enzyme and $30^{\circ}C$ for the free enzyme, respectively. The immobilized enzyme had no loss of activity after 10 cycles, and retained more than 90% of its original activity after storage for 30 days. After immobilization, the enzyme activity was only slightly affected by $Hg^{2+}$, which completely inhibited the activity of the free enzyme. The immobilized tannase was used to remove 80% of tannins from a green tea infusion on the first treatment. The beads were used for six successive runs resulting in overall hydrolysis of 56% of the tannins.

• 한국식품영양과학회지
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• 제24권4호
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• pp.570-577
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• 1995

Aspergillus sp. SB-2704 was selected for its strong polygalacturonase activity among various strain of mold found in soil. It was found that production of polygalacturonase reached to maximum when the wheat bran medium containing 1% polypepton, 1% glucose, and 0.2% FeSO4 were cultured for 3 days at 35$^{\circ}C$. Polygalacturonase was purified 20.90 fold from Aspergillus SB-2704. The purification procedures include ammonium sulfate treatment, gel filtration on Sephdex G-150 and DEAE-cellulose ion exchange chromatography. Yield of the enzyme purification was 4.34%. Purified enzyme was confirmed as a single band by the polyacrylamide gel electrophoresis. When the purified enzyme was applied to SDS-polyacrylamide gel electrophoresis, the molecular weight was estimated to be 36,000. The optimum pH for the enzyme activity was 5.5 and optimum temperature was 5$0^{\circ}C$. The enzyme is stable in acidic condition. The activity of purified enzyme was inhibited by Pb2+, Hg2+ and Ba2+, whereas activated by Cu2+, Mn2+, Mg2+ and Fe2+. The activity of polygalacturonase was inhibited by the treament wit maleic anhydride, iodine, and EDTA. The result indicate the possible involvement of histidine and metal ion at active site.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권3호
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• pp.73-81
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• 2013

Various remediation methods have been applied to clean soils contaminated with pollutants. They remove contaminants from the soils by utilizing physicochemical, biological, and thermal processes and can satisfy soil remediation standards within a limited time; however, they also have an effect on the biological functions of soils by changing soil properties. In this study, changes of the biological properties of soils before and after treatment with three frequently used remediation methods-soil washing, land farming, and thermal desorption-were monitored to investigate the effects of remediation methods on soil biological functions. Total microbial number and soil enzyme activities, germination rate and growth of Brassica juncea, biomass change of Eisenia andrei were examined the effects on soil microorganisms, plant, and soil organisms, respectively. After soil washing, the germination rate of Brassica juncea increased but the above-ground growth and total microbial number decreased. Dehydrogenase activity, germination rate and above-ground growth increased in both land farming and thermal desorption treated soil. Although the growth of Eisenia andrei in thermal desorption treated soil was higher than any other treatment, it was still lower than that in non-contaminated soil. These results show that the remediation processes used to clean contaminated soil also affect soil biological functions. To utilize the cleaned soil for healthy and more value-added purposes, soil improvement and process development are needed.

• 한국토양비료학회지
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• 제15권4호
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• pp.241-250
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• 1982

발아초기 녹두의 부위별 alkaline inorganic PPase의 활성변화 및 잎 부위에서 부분 정제하여 얻은 효소를 이용하여 효소적 성질을 조사한 결과를 요약하면 다음과 같다. 1. 잎 부위가 타 부위보다 약 2~4배의 더 높은 활성을 나타냈으며 발아가 진행됨에 따라 잎과 뿌리 그리고 지엽에서는 효소 활성이 초기에 증가하다가 점차 감소하는 경향을 보인 반면, 상배축에서는 초기부터 계속 감소하였으며 하배축에서는 계속 증가하는 경향을 보였다. 2. 정제 과정동안 23.9%의 수율로 86배가 정제되었으며 전기 영동상의 Rm value는 0.35였으며 homogenenity는 아니었고, Km value는 0.89mM로 나타났다. 3. 이 효소는 $Mg^{2+}$에 대해 대단히 Specific하였으며 $Cu^{2+}$와 $Fe^{2+}$도 $Mg^{2+}$에 비해 각각 56%, 55%의 activating effect를 나타냈다. 그러나, $Cu^{2+}$, $Zn^{2+}$, $Mn^{2+}$, $Co^{2+}$와 $Ni^{2+}$은 이 효소에 대해 저해체로 작용하였다. 4. 이 효소는 pH 8-9와 $50^{\circ}C$에서 최대의 활성을 보였으며 열에 대해서도 상당히 안정하였다.

• Journal of Microbiology and Biotechnology
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• 제11권6호
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• pp.957-963
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• 2001

Bacillus subtilis YL-1004 was isolated from soil for the development of agents to control dental caries. This strain produced an extracellular lytic enzyme that hydrolyzed the Streptococcus mutans cell wall. The lytic enzyme was purified to homogeneity by affinity chromatography and gel permeation chromatography to give a single band on SDS-PAGE and non-denaturing polyacrylamide gel electrophoresis. The molecular weight of the enzyme was deduced from SDS-PAGE and gel chromatography to be 38 kDa and the PI to be 4.3 from isoelectric focusing. Sirty $\%$ of its lytic activity remained after incubation at $50^{\circ}C$ for 30 min, and its optimal temperature was $37^{\circ}C$ . The enzyme showed its highest activity at pH 8.0 and was stable at pHs ranging from 4.0 to 9.0. Treatment with several modifiers showed that a cysteine residue was involved in the active site of the enzyme. This lytic enzyme from Bacillus subtilis YL-1004 exhibited specificity towards Streptococci and also showed autolytic activity on Bacillus subtilis YL-1004.