• Journal of Life Science
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• 제11권2호
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• pp.92-93
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• 2001

Bacillus sp. KYJ 963, which was isolated from Korean salt-fermented anchovy (anchovy-jeot), produces an extracellular ${\beta}$-amylase. The analysis of the digestion products of substrates by thin layer chromatography from the purified protein revealed that the enzyme could not hydrolyze maltose or ${\alpha}$-cyclodextrin. In the amino acid composition analysis, the major characteristic of the ${\beta}$-amylase was the high proportion of amino acids that possess short side chain such as glycine and alanine.

• 한국미생물·생명공학회지
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• 제28권1호
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• pp.59-61
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• 2000

The various extracellular enzymes produced by lactic acid bacteria isolated from kimchi were assayed to improve the shelf-life of kimchi. Peroxidase was not detected in all tested lactic acid bacteria and small amount of ascorbic acid oxidase was detected in Pediococcus pentosaceus and Lactobacillus brevis. In case of $\alpha$-amylase, 27.8 and 20.9 unit/mg were shown in Pediococcus acidilactici and Pediococcus pentosaceus, respectively but $\beta$-amylase and protease activities were very low. The enzyme related to textural property of kimchi, pectinesterase showed low activity but polygalacturonase activity was 0.28 unit/mg in Lactobacillus homohiochii and 0.27 unit/mg in Lactobacillus plantarum.

• Journal of the Korean Wood Science and Technology
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• 제19권2호
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• pp.22-29
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• 1991

The endo-1,4-${\beta}$-xylanase was extracted and purified from the extracellular xylanolytic systems of Trichoderma viride. The crude enzyme was chromatographed with ion-exchange reins of DEAE Sepharose CL-6B, Sepharose, S-Sepharose CL-6B and the resulting xylanase was turned out to be a single protein as 20KD hy SDS-polyacrylamide gel electrophoresis. The xylooligomers were obtained from xylan by incubation with the purified xylanase up to 50%. The ${\beta}$-xylosidase lost its activity completely by incubation of crude enzyme for 24hr with buffer solution of pH 2.8 at $27^{\circ}C$. And also, the xylooligomers were obtained from xylan as a main product by incubation with the crude enzyme treated with acidic buffer.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1998년도 Proceedings of UNESCO-internetwork Cooperative Regional Seminar and Workshop on Bioassay Guided Isolation of Bioactive Substances from Natural Products and Microbial Products
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• pp.161-161
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• 1998

To achieve the aim of this investigation, the extracellular protease was isolated from bacteria BAC-4, a strain was cultivated in the medium for the production of penicillin acilase in a period of 32 hours. The enzyme was first purified by aceton precipitation method, followed by ion exchange chromatography on DEAE-sephacel column. The highest specific activity of the aceton fraction was found to be 2.19 unit per mg, with degree of purification of 13 times. Further purification of the enzyme on DEAE -sephacel had a specific activity of 58.6 unit per mg and degree of purification of 344 times compared to its crude extract. The optimum pH of the enzyme was 8.4, and the potimum temparature was 37$^{\circ}C$. The K$\_$M/ and $V_{max}$ calculated at experiment conditions were found to be 0.66%(W/V) and 3.61 unit per mL respectively.

• 미생물학회지
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• 제30권6호
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• pp.507-513
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• 1992

Serratia marecescens RH1 isolated from soil samples produced large amount of extracellular proteases. One of the genes encoding an extracellular protease form S. marcescens RH1 was cloned in Escherichia coli by shot gun cloning method. The cloned protease, SSP, was stably expressed by its own promoter and excreted into the extracellular medium from E. coli host (ORF) of 3.135 nucleotides corresponding to 1.045 amino acids (112 kDa). The nucleotide and deduced amino acid sequence of SSP showed high overall homology (88%) to one of the S. marcescens protease (27), but low homology to other serine protease families. The optimal pH and temperature of the enzyme were pH 9.0 and 45.deg.C respectively. The activity of protease was inhibited by phenylmethylsulfonyl fluoride (PMSF), which suggests that the enzyme is a serine protease.

• Journal of Microbiology and Biotechnology
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• 제17권5호
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• pp.745-752
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• 2007

A $\beta$-glucosidase from the algal lytic bacterium Sinorhizobium kostiense AFK-13, grown in complex media containing cellobiose, was purified to homogeneity by successive ammonium sulfate precipitation, and anion-exchange and gel-filtration chromatographies. The enzyme was shown to be a monomeric protein with an apparent molecular mass of 52 kDa and isoelectric point of approximately 5.4. It was optimally active at pH 6.0 and $40^{\circ}C$ and possessed a specific activity of 260.4 U/mg of protein against $4-nitrophenyl-\beta-D-glucopyranoside$(pNPG). A temperature-stability analysis demonstrated that the enzyme was unstable at $50^{\circ}C$ and above. The enzyme did not require divalent cations for activity, and its activity was significantly suppressed by $Hg^{+2}\;and\;Ag^+$, whereas sodium dodecyl sulfate(SDS) and Triton X-100 moderately inhibited the enzyme to under 70% of its initial activity. In an algal lytic activity analysis, the growth of cyanobacteria, such as Anabaena flos-aquae, A. cylindrica, A. macrospora, Oscillatoria sancta, and Microcystis aeruginosa, was strongly inhibited by a treatment of 20 ppm/disc or 30 ppm/disc concentration of the enzyme.

• 미생물학회지
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• 제22권4호
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• pp.257-263
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• 1984

토양시료로 부터 cytosine과 5-fluorocytosine에 특이성을 갖는 세포의 cytosine deaminase를 생산하는 균주 JH-13을 분리하였다. 분리균 JH-13을 분류학적으로 검색한 결과 Arthrobacter 속에 속하는 것으로 밝혀졌으며 Arthrobacter JH-13으로 명명하였다. 분리 균의 세 포외 cytosine deaminase 생성을 위한 최적배지의 조성은 peptone 0.5%, meat extract 0.5%, soluble starch 0.5%, KCl O.1%로, 배지의 초발 pH 는 8.0으로 설정하였다. 500 ml용량의 진탕 flask에 최적배지 100 ml를 넣고 110 Rev.${\times}6$cm stroke로 $30^{\circ}C$에서 진탕배양하였을 때 효소생산은 54시간 부근에서 최고에 달하였다.

• The Korean Journal of Ecology
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• 제17권1호
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• pp.79-90
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• 1994

1991년 11월부터 1992년 8월까지 총 8회에 걸쳐 금강하구에서 고군산군도까지 6개 정점을 대상으로 종속영양 세균의 분포와 평군체적 및 세포와 효소활성을 측정하였다. 해양성 종속영양 세균은 1.0X103~5X105 c.f.u./ml의 범주에서 분포하였으며, 간균이 45~72%를 차지하였다. 또한 구균의 평균체적은 (7.69$pm$0.18)X10-2~(8.18$pm$0.38)X10-2$mu$m3, 간균은 (6.09$pm$0.29)X10-2~(7.72$pm$0.41)X10-2$mu$m3의 범주에서 변화하였다. 세포외 효소활성도를 측정한 결과, glucosidase의 활성은 0~3.49$mu$M/l/hr, chitinase의 활성은 0~1.25$mu$M/l/hr, phosphatase는 0~11.95$mu$M/l/hr, amylase는 0~3.80$mu$M/l/hr의 범주에서 측정되어 세포외 효소활성은 여름철에 높은 값을 보였으며, 측정효소중 phosphatase의 활성이 가장 높았다. 종속영양 세균의 분포와 세포외 효소활성은 수온과 유입되는 유기물의 양과 밀접한 관계가 있었으며, 세균의 체적의 크기는 세포외 효소 활성과는 직접적인 관계가 없었다.

• 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)

• 미생물과산업
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• 제12권2호
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• pp.36-39
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• 1986