• Microbiology and Biotechnology Letters
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• v.42 no.4
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• pp.324-330
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• 2014

A marine bacterial strain producing agar-degrading enzymes was isolated from a mud flat in Jeboo-do (Korea) using a selective artificial sea water (ASW) agar plate containing agar as the sole carbon source. The isolate, designated as SH-1, was gram-negative, aerobic, and motile with single polar flagellum. 16S rRNA gene sequence similarity analysis showed the isolate SH-1 had the highest homology (96.5%) to marine bacterium Neiella marina J221. Cells could grow at $28-37^{\circ}C$ but not at $42^{\circ}C$, and the agarase activity of the cell culture supernatant was higher when grown at $28^{\circ}C$ than when grown at $37^{\circ}C$. Cells could grow when concentrations of 1-5% (w/v) NaCl were added to the growth media with the best growth observed at 3% NaCl, and the agardegrading enzyme activity of the cell culture supernatant was best when grown at 3% NaCl-containing growth media under the conditions we examined. The crude enzyme prepared from 48-h culture broth of strain SH-1 exhibited an optimum pH and temperature for agar-degrading activity at 7.0 and $40^{\circ}C$, respectively. Zymogram analysis of the crude supernatant and cell extract showed that strain SH-1 produced at least 3 agar-degrading enzymes with molecular weights of 15, 35, and 52 KD. Thinlayer chromatography (TLC) analysis also suggested that HS-1 produces ${\beta}$-agarase to degrade agarose to neoagarooligosaccharides.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1976.10a
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• pp.189.3-189
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• 1976

흙으로부터 분리된 곰팡이 144주와 식품공학과에 보존하고 있는 곰팡이 60주로부터 121주가 endo-polygalacturonase의 활성을 나타냈다. 그 중 효소생산이 좋은 Aspergillus sp. A-2를 선정하여 배양생산된 효소에 관하여 연구한 결과는 다음과 같다.(중략)

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1976.10a
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• pp.190.4-190
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• 1976

Naringinase 생산 균주로 분리 선정된 Asp. niger S-1은 동시에 Hesperidinase도 강력히 생산함이 확인 되었으며 이 균의 효소학적 특성을 요약하여 1. 최적 반응 온도는 $60^{\circ}C이며$ $80^{\circ}C에서$ 30분 열처리 하여도 65%을 활성을 가지며 pH 5.0부위에서 최적반응과 안정성을 보였으며 Mg(이온)은 반응을 활성화 하였다. 2. Aceton을 60% 처리하여 조효소를 11배 정제하였으며 35%가 회수되었고 유안 0.4-0.6 포화로 48배 정제되었으며 13%가 회수되었다.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 1986.12a
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• pp.517.1-517
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• 1986

고온 호알카리성 Bacillus K-17의 Protease gene의 구조해명과 성질을 알기 위해서, E. coli HB101에 pER 322를 Vector로 하여 Protease gene을 Cloning하여 형질전환 된 균주를 선정하였다. 선정균주의 pretense activity를 Bacillus K-17의 상대활성도와 매우 유사하였으며 균체외에 보다 많은 효소 활성도를 지니고 있었다. 제한효소 Hind III로 절단하면 약 1.8kb와 0.4kb의 2개의 fragments 가 생성되었으며 Southern hybridization 결과 Cloning 된 gene이 Bacillus K-17에서 유래된 것임이 확인되었다.

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.47-50
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• 2001

고분자의 생분해는 미생물에 의하여 분비되는 효소를 촉매로 하여 산화, 가수분해 등의 반응이 일어나 진행된다. 고분자의 생분해성에 영향을 미치는 요소는 다양하여 고분자 자체의 분자구조뿐만 아니라 분해되는 환경조건과도 관련되어있다. 특히 고분자를 분해시키는 미생물과 분해에 직접적인 촉매로 작용하는 효소는 대부분 수분이 있는 조건에서 활성이 크기 때문에, 수분의 접근성과 침투정도는 생분해에 중요한 요인으로 작용한다. (중략)

• Korean Journal of Microbiology
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• v.35 no.4
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• pp.277-282
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• 1999

A bacterium producing the extracellular cellulase was isolated from cattle feces and screened as cellulase activity was excellent upon congo red straining method and activity measurements. Isolate was identified as Bacillus subtilis CH-10 on the basis of morphological and biochemical properties as well as cellular fatty acids composition. The enzyme which the isolate secretes had the optimum initial pH and temperature for its induction was 7.5 and 50${\circ}C$, respectively. The maximum CMCase activity in crude enzyme solution was observed at pH 7.5 and 75${\circ}C$ and was stable for pH 7.5 to 9.0 to maintain 70% activity. When the isolate was cultured in CMC media at 37${\circ}C$ for 24 hrs, CMCase and FPase activity was 1.13 U/㎖and 0.16U/㎖, respectively whereas Avicelase and ${\beta}$-glucosidase activity was not detected. When crude supernatant was used for zymogram, three major bands, cel 1, cel 2 and cel 3, were detected approximately 39, 41 and 57 KDa, respectively on CMC-SDS-PAGE.

• Korean Journal of Microbiology
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• v.33 no.2
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• pp.136-141
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• 1997

To elucidate whether there are bacteria excreting proteases in Korean traditional fermented food, soybean paste (Doen-Jang) or not, well growing bacteria with halos were isolated on the qkim milk agar media. The strains were identified as Bacillu, cereus JH-1, B. cereus SH-5, B. cereus SH-7 through various physiological and biochemical tests, VlTEK system, and MIDI system. The extracellular proteases of the strain JH-1, and SH-5, were optimal at pH 9, 40^{\circ}C.$, and the protease of strain SH-7 at pH 8 and 50^{\circ}C.$. Also hemolysis activities of the three strains were observed on the hlood agar media.

• Microbiology and Biotechnology Letters
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• v.49 no.3
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• pp.403-412
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• 2021

This study aimed to identify plant growth-promoting activity, phytopathogenic fungi growth inhibitory activity, mineral solubilization ability, and extracellular enzyme activity of the genus Bacillus in soil and the rhizosphere. With regards to antifungal activity against phytopathogenic fungi, DDP257 showed antifungal activity against all 10 pathogenic fungi tested. ANG20 showed the highest ability to produce indole-3-acetic acid, a plant growth-promoting factor (70.97 ㎍/ml). In addition, 10 species were identified to have 1-aminocyclopropane-1-carboxylate deaminase production ability, and most isolates showed nitrogen fixation and siderophore production abilities. Thereafter, the isolated strains' ability to solubilize minerals such as phosphate, calcite, and zinc was identified. With extracellular enzyme activity, the activity appeared in most enzymes. In particular, all the strains showed similar abilities for alkaline phosphatase, esterase (C4), acid phosphatase, and naphtol-AS-BI-phosphohydrolase production. This result was observed because the genus Bacillus secreted various organic substances, antibiotics, and extracellular enzymes. Therefore, through the results of this study, we suggest the possibility of using strains contributing to the improvement of the soil environment as microbial agents.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.4
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• pp.234-241
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• 2007

Biological amendments consisting of suspensions of selected microorganisms are often used in conjunction with various organic materials for amending soils to improve soil quality and plant growth. The effects of the biological amendment on chemical and biological properties of soil were investigated for a biological amendmentalone and when combined with different organic materials includingmunicipal compost (MC), poultry litter (PL), and cover crops (red clover (RC) and spring oats). A liquid preparation of a biological amendment called Effective Microorganisms was sprayed on the tested plots three times over a two-year period. Effective Microorganisms alone did not influence pH, K, or organic matter content in soil. However, increases in P in PL-treated soils in fall of both years andCa in MC-treated soil in fall 2001, and decreases in Ca, Mg, and cation exchange capacity (CEC) in RC-planted soil were associated with EM. Increased dehydrogenase(DH) activitiesassociated with Effective Microorganismswere only detected in July (P=0.0222) and October (P=0.0834) for RC-planted soils in the first year. Fluorescein diacetate (FDA) hydrolysisappeared to be enhanced by Effective Microorganisms in soils untreated or treated with MC and oatsbut only sporadically during the sampling period. FDA hydrolysis in both PL- and RC-treated soils as well as DH activity in PL-treated soils decreased with Effective Microorganisms treatment. Effective Microorganisms did not influence substrate utilization patterns expressed by the BIOLOG assay. We conclude that Effective Microorganisms effects on soil chemical and biological properties varied depending on the added organic materials. Effective Microorganisms periodically increased soil DH activity and FDA hydrolysis with RC and with MC plus oats, respectively.

• Microbiology and Biotechnology Letters
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• v.18 no.5
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• pp.490-495
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• 1990

The extracellular inulinase from Bacillus spp. was purified to a single protein through a sequence of operations including ammonium sulfate fractionation, heat treatment, DEAE Sepharose C1-6B ion exchange chromatography, Sephadex 6-100 and Sephadex 6-150 gel filtration. The purified enzyme was confirmed to be a $\beta$ -D-fructofuranosidase(EC 3.2.1.26) which was much more active on sucrose than on inulin(I/S = 0.2). The maximal inulinase activity was observed at pH 6.0 and at the temperature of $50^{\circ}C$. The mo1ecular weight of the enzyme was about 56, 000. Tryptophan and histidine residues of the enzyme molecule were found to be essential for its catalytic activity.