• The Plant Pathology Journal
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• 제37권6호
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• pp.580-595
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• 2021

Although late blight is an important disease in ecofriendly potato cultivation in Korea, it is highly dependent on the use of eco-friendly agricultural materials and the development of biological control technology is low. It is a necessary to develop an effective biocontrol agent to inactivate late blight in the field. AFB2-2 strain is a gram-positive with peritrichous flagella. It can utilize 20 types of carbon sources, like L-arabinose, and D-trehalose at 35℃. The optimal growth temperature of the strain is 37℃. It can survive at 20-50℃ in tryptic soy broth. The maximum salt concentration tolerated by AFB2-2 strain is 7.5% NaCl. AFB2-2 strain inhibited the mycelial growth of seven plant pathogens by an average inhibitory zone of 10.2 mm or more. Among the concentrations of AFB2-2, 10⁷ cfu/ml showed the highest control value of 85.7% in the greenhouse. Among the three concentrations of AFB2-2, the disease incidence and severity of potato late blight at 10⁷ cfu/ml was lowest at 0.07 and 6.7, respectively. The nucleotide sequences of AFB2-2 strain were searched in the NCBI GenBank; Bacillus siamensis strain KCTC 13613, Bacillus velezensis strain CR-502, and Bacillus amyloliquefaciens strain DSM7 were found to have a genetic similarity of 99.7%, 99.7%, and 99.5%, respectively. The AFB2-2 strain was found to harbor the biosynthetic genes for bacillomycin D, iturin, and surfactin. Obtained data recommended that the B. velezensis AFB2-2 strain could be considered as a promising biocontrol agent for P. infestans in the field.

• 한국미생물·생명공학회지
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• 제17권4호
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• pp.327-333
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• 1989

미생물에 의한 적자색 색소를 생산하기 위하여 Streptomyces propurpuratus ATCC 21630과 토양에서 분리한 strain No.89를 한천배지상에서 혼합배양하여 적자색을 형성하였다. 적자색 색소를 형성하는 strain No89는 Bacillus sp. R-89로 명명하였다. 이들 두 균주는 각각 배양하였을 때는 색소를 형성하지 않았다. 적자색 색소를 많이 생산하기 위해 Streptomyces Propurpuratus ATCC 21630를 MNNG (N-methyl-N'-nitro-N-nitrosoguanidine) 로 처리하여 얻은 변이주 S.P-6과 Bacillus sp. R-89를 생산배지에서 혼합하여 발효하였을 때 1420$\mu\textrm{g}$/$m\ell$의 색소를 얻을 수 있다.

• 한국수산과학회지
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• 제42권5호
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• pp.461-467
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• 2009

A bacterial strain was screened and identified from sea sediments in Tongyeong coastal area in order to obtain proteases or peptidase cleaving C-terminal of glutamic acid. Strain TS0611, which showed the highest activity from 5 isolated protease producing strains, was selected and its properties investigated. Strain TS0611 was a gram-positive rod, $1.2\;{\mu}m$ in cell length, catalase positive, motility-positive, melanin-negative and grew at 15~$50^{\circ}C$, and hydrolyzed gelatin and casein. This strain was identified as Bacillus thuringiensis or Bacillus cereus based on results from the API system(API 50 CHB) which examined saccharides properties, fatty acid composition of cell wall, and 16S rRNA gene sequence.

• 한국미생물·생명공학회지
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• 제19권5호
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• pp.464-469
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• 1991

$\alpha$-Amylase를 생산하는 Bacillus sp. 2B를 토양에서 분리하였으며 이 균주에 반복적으로 돌연변이원인 NTG를 처리하여 효소생산성이 증대된 변이주를 유도하였다. $\alpha$-Amylase 고 생산성 균주의 효율적인 획득방법으로 glucose에 의한 $\alpha$-amylase의 생성억제를 받지않는 변이주를 분리한 결과, 효소생산성이 약 30배 향상된 변이주 Bacillus sp. HG4를 획득하였다. 이 균주는 lactose를 탄소원으로 하여 최대 효소생성능을 나타내었으며 빠른 균체성장 및 최대 효소생성시기에 균체 lysis가 적은 점 등 산업적으로 사용하기에 유리한 특성을 가진 것으로 판단된다.

• 생명과학회지
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• 제10권1호
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• pp.101-106
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• 2000

과즙 및 과실주 제조에서 착즙 수율 향상, 혼탁방지, 삼의 벌효정제, 식물 조직배양들에 pectinase가 널리 이용되고 있다. 본연구에서는 삼지닥나무의 이용 및 응용하는 연구의 일환으로서 토양으로 부터 높은 pectinase 활성을 나타내는 균주를 분리, 동정하여 삼지닥나무를 분해시키는 pecrinase의 생산조건을 검토하였다. 경남일대에서 채취된 토양시료 100여점으로 부터 pectinase 활성이 높은 6균주의 형태학적, 생화학적특성을 조사하여 동정한 결과 Bacillussp.로 밝혀졌다. Bacillus sp.BS-214의 배양 특성과 pectinase 생성조건을 검토한 결과 온도 4$0^{\circ}C$,pH8.5, 배양시간 36시간에서 효소생산이 가장 양호햐였다. 균의 생육과 효소 생산에는 탄소원으로 1%의 농도의 polygalacturonic acid 와 질소원으로서 0.25%의 yeast extract가 가장 적합하였으며, 본 균주에서 생산된 효소에 의한 삼지닥나무의 펙틴질 분해도 관찰되었다.

• 한국미생물·생명공학회지
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• 제24권3호
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• pp.299-303
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• 1996

Isolation, identification, and culture conditions of a lytic enzyme producing microorganism against Lacto- bacillus plantarum were investigated. The selected strain was gram-positive, rod (0.7 $\times$ 2.7 $\mu$m in size), and non-motile. The strain did not have any flagella and spores. According to its cultural and physiological characteristics, the strain was identified as Bacillus sp. The optimal pH and temperature for the production of lytic enzyme were 8.0 and 30$\circ$C, respectively. The maximum enzyme activity showed 1.5 units/ml in the medium composed of 1% peptone and 0.1% NaCl.

• 한국미생물·생명공학회지
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• 제22권3호
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• pp.227-232
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• 1994

In order to microbially control root-knot nematode(Meloidogyne incognita) in tomato, a strain BtTH109 of Bacillus thuringiensis producing root-knot nematocidal toxin was isolated. The strain BtTH109 was identified B. thuringiensis subsp. indiana(serotype 16) based on flagella antigenicity, biochemical properties, and morphological charcateristics. The strain BtTH109 have extracellularly produced a root-knot nematocidal toxin, which was very toxic against not only egghatch but also the 2nd-nematode larva of root-knot nematode in vitro.

• 한국유기농업학회지
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• 제12권1호
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• pp.101-114
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• 2004

This study was carried out to clarify the effects of antagonistic microorganism, Bacillus sp. JC181 isolated from the greenhouse soil grown cucumber plants on the growth inhibition of plant pathogen, fusarium wilt (Fusarium oxysporum) occurred in cucumber plants in greenhouse. Antagonistic bacterial strains were isolated and were investigated into the antifungal activity of the antagonistic microorganism against fusarium wilt. Screened fourteen bacterial strains which strongly inhibited F. oxysporum were isolated from thc greenhouse soil grown cucumber plants, and the best antagonistic bacterial strain designated as JC181, was finally selected. Antagonistic bacterial strain JC181 was identified to be the genus Bacillus sp. based on the morphological and biochemical characterization. Bacillus sp. JC181 showed 58.2% of antifungal activity against the plant pathogen growth of F. oxysporum. By the bacterialization of culture broth and heated filtrates of culture broth, Bacterial strain, Bacillus sp. JC181. showed 91.2% and 260% of antifungal activity against F. oxysporum, respectivrly.

• 한국미생물·생명공학회지
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• 제28권4호
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• pp.219-222
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• 2000

To produce and utilize microbial cyclomaltodextrinase being industrially useful, we isolated an alkalophilic Bacillus strain from soil which was capable of degrading cyclodextrins. The newly isolated strain was aerobic, gram-positive, spore-forming, motile, rod shape(0.2~0.4$\times$1.4~4.4 $\mu\textrm{m}$), and 35.8 mol% of DNA base composition. Based on its morphological, phisiological, and biochemical properties, it was identified as alkalophilic Bacillus sp. KJ-133 and cultivated well in the ranges of $30~40^{\circ}C$ and pH 8.0~9.0 . The cyclomaltodextrinase of the strain showed maximal production after 48h of cultivation at $37^{\circ}C$, and the activity was inhibited by Ag2+, Hg2+, Cu2+, and p-chloromercuribenzoate.

• 생명과학회지
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• 제9권4호
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• pp.489-492
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• 1999

A bacteial strain which can produce the extracellular fibrinolytic enzyme was isolated from Jeot-Gal (anchovy) that was Korean traditional salt-fermented fish. The isolated bacterium was identified to be a strain of Bacillus sp. The optimal medium for fibrinolytic enzyme production was determined to consist of 5 g maltose, 10 g defatted soybean, 20 g sodium chloride, 1.75 g K2HPO4 per liter (pH 7.0)