• 한국식품영양학회지
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• 제5권2호
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• pp.132-136
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• 1992

Streptomyces sp. YB-88-20 was Isolated from soil and the properties of chitobiase were investigated. The optimal reaction condition for the enzyme was pH 5.5 and 4$0^{\circ}C$ , and was stable in the range of pH 4. 0 to 5.5 and temperature at 4$0^{\circ}C$, and 40 min, respectively The enzyme was inactivated by heating at 45$^{\circ}C$ for 1 hr. The enzyme was slightly activated by Mna+. Mg2+, but inhibited by Fea+. Km and activation energy was 1.5072 M and 8.314 kcal/mol.

• 생명과학회지
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• 제12권1호
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• pp.43-48
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• 2002

토양으로 부터 혈전용해효소를 생산하는 방선균을 분리하여, 본 방선균이 생산하는 혈전용해효소의 최적 생산 조건을 검토하였다. 생산균주는 회색의 기균사를 생성하며 약 0.6~0.8$\times$0.4~0.8$\mu\textrm{m}$ 크기의 원통형 포자를 가지며 포자의 표면은 매끈하며, 약 10~40개의 포자가 고리를 이루고 있는 형태를 나타내었다. 이상의 결과로 본 균주는 Sfreptomyces 속으로 추정되어 Streptomyces sp. JK-20로 명명하였다. 본 균주의 생리학적 특성으로 20~32$^{\circ}C$의 온도에서 생육 가능하며 최적 생육 온도 및 pH는 24$^{\circ}C$ 및 pH 6이었다. 본 균주의 혈전용해효소의 생산을 위한 최적 생산 조건을 검토한 결과 탄소원으로 1% xylose였고 질소원은 0.5% yeast extract, 0.5% polypeptone, 금속염은 0.1% MgSO$_4$.7$H_2O$였으며 인산염은 0.1% NaH$_2$Po$_4$.2$H_2O$이었다. 본 생산 균주를 최적 배지 조건에서 배양하였을 때 배양 4일째에 혈전용해효소의 생산력이 가장 높았다.

• 한국균학회지
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• 제19권3호
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• pp.231-237
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• 1991

참깨 시들음병과 역병에 대한 괄항균(括抗菌) Streptomyces spp.의 길항현상과 생물학적 방제 효과를 구명코져 참깨 시들음병(F. oxysporum f. sp. vasinfectum)과 역병(P. nicotianae var. parasitica)이 발생한 포장에 이병주로 부터 병원균을 순수분리(純粹分離)하였고 괄항균(括抗菌)은 충북일원의 고추, 참깨포장의 72점의 흙으로 부터 공시 병원균에 효과있는 괄항균(括抗菌)을 대치배양법(對峙培養法)으로 선발하였다. 선발된 괄항균(括抗菌) St-11 과 St-20 을 공시하여 병원균에 대한 균사저지원, 괄항균(括抗菌) 배양 여액에서의 병원균의 생육저지, 발아억제 빛 lysis 를 관찰 조사하였고 괄항균(括抗菌) 현독액(縣獨液 )(St-11) 을 종자에 처리할 경우 참깨생육에 아무런 영향이 없었다. 온실에서 괄항균(括抗菌)의 토양접종에 의한 참깨시들음병과 역병에 대한 방제효과는 병원균 단독 접종구에 비하여 40-78% 의 방제효과를 보였다.

• Journal of Microbiology and Biotechnology
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• 제20권12호
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• pp.1689-1695
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• 2010

Pantothenate kinase (PanK) catalyzes the first step in the biosynthesis of the essential and ubiquitous cofactor coenzyme A (CoA) in all organisms. Here, we report the identification, cloning, and characterization of panK-sp from Streptomyces peucetius ATCC 27952. The gene encoded a protein of 332 amino acids with a calculated molecular mass of 36.8 kDa and high homology with PanK from S. avermitilis and S. coelicolor A3(2). To elucidate the putative function of PanK-sp, it was cloned into pET32a(+) to construct pPKSP32, and the PanK-sp was then expressed in E. coli BL21(DE3) as a His-tag fusion protein and purified by immobilized metal affinity chromatography. The enzyme assay of PanK-sp was carried out as a coupling assay. The gradual decrease in NADH concentration with time clearly indicated the phosphorylating activity of PanK-sp. Furthermore, the ca. 1.4-fold increase of DXR and the ca. 1.5-fold increase of actinorhodin by in vivo overexpression of panK-sp, constructed in pIBR25 under the control of a strong $ermE^*$ promoter, established its positive role in secondary metabolite production from S. peucetius and S. coelicolor, respectively.

• 한국미생물·생명공학회지
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• 제28권3호
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• pp.161-166
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• 2000

Monilinia fructicola에 의해 감염되어 미이라화된 복숭아 열매로부터 Monilinia fructicola에 강한 항진균성 물질 chitinase 및 urease을 분비하는 방선균을 분리하였다 선발된 TH-04 균주는 배양적 .형태적 특성 세포벽 성분 및 세포내 당 성분을 분석한 결과 전형적인 Streptomyces속에 속하는 방선균으로 동정되었다. TH-04 균주는 Monilinia fructicola Colletotrichum gloeosporioides Magnaporthe grisea Rhizoctonia solani, Phytophthora capsici, Alternaria kikuchi-ana, Fusarium solani 및 Fusarium oxysporum 등 8종의 식물병원균에 대하여 항진균 활성을 나타냈다. 항생물질 생산을 위한 배양조건은 온도 $20^{\circ}C$, pH 7 및 배양기간 7일로 확인되었다.

• 생명과학회지
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• 제20권11호
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• pp.1582-1588
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• 2010

전 연구에서 해양세균 Streptomyces sp. M3의 새로운 alginate 분해효소를 signal peptide가 제거된 상태로 클로닝하고 E. coli BL21 (DE3) 균에 형질전환시켰다. 본 연구에서는 배양할 때 IPTG를 첨가하여 M3 alginate 분해효소 단백질을 과발현시키고 Ni-Sepharose 친화력 chromatography로 정제하여 생화학적 성질을 조사하였다. 기질특이성을 시험하기 위한 235 nm에서의 흡광도와 TLC 분석 결과로부터 M3 alginate 분해효소가 polyG block에 기질특이성을 나타냄을 알 수 있었다. M3 분해효소를 기질과 10분 동안 반응시켰을 때, 최적 pH 및 최적온도는 pH 9 및 $60^{\circ}C$이었다. 1 mM $Ca^{++}$ 및 $Mn^{++}$은 alginate 분해활성을 2배 증가시킨 반면 $Hg^{++}$ 및 $Zn^{++}$는 분해활성을 완전히 저해하였다. $Mg^{++}$, $Co^{++}$, $Na^+$, $K^+$, 및 $Ba^{++}$은 M3 alginate 분해효소의 활성에 거의 영향을 미치지 않았다.

• 한국미생물·생명공학회지
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• 제23권3호
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• pp.329-336
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• 1995

For the development of new antitumor antibiotics produced by microorganisms, Streptomyces sp. YBE-316 was isolated from soil. The productivity of the antitumor antibiotic from Streptomyces sp. YBE-316 gradually increased after 60 hours, and was maximum after 100 hours after inoculation in growth medium (2.0% sucrose, 1.0% soybean meal, 0.1% K$_{2}$HPO$_{4}$, pH 7.0) at 30$\circ$C, 150 rpm, 5 NL/min by 30 l jar fermentor. This antitumor antibiotic was present only in mycelium, and stable in pH 5.0-10.0 for 20 minutes at 100$\circ$C. Antitumor and antibiotic activities were maintained at neutral pH, and heat stability was low. This antitumor antibiotic was soluble in methanol and ethanol, and insoluble in water, ethyl acetate, chloroform, and n-hexane. This antitumor antibiotic was sequentially purified by acetone extraction from mycelium, butanol extraction, and silica gel column chromatography. Antitumor activity was low against most tested cell lines, but antibiotic activity was high and low against yeasts and bacteria, respectivelv. The visualization test showed that this antitumor antibiotic had higher hydroxyl, ketone, amino, carboxyl groups, and sugar(s) in its structure. Instrumental analyses showed that this antitumor antibiotic was a pentaene in polyene class antibiotics. In pentaene class antibiotics, this was considered as an eurocidin or capacidin type antibiotics. The molecular weight of this antitumor antibiotic was higher than 683.0 daltons, and this antitumor antibiotic might be glycosylated by other sugar(s), instead of mycosamine or perosamine, an amino sugar.

• BMB Reports
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• 제36권2호
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• pp.185-189
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• 2003

Chitinase (EC 3.2.1.14) was isolated from the culture filtrate of Streptomyces sp. M-20 and purified by ammonium sulfate precipitation, DEAE-cellulose ion-exchange chromatography, and Sephadex G-100 gel filtration. No exochitinase activity was found in the culture filtrate. The molecular mass of the purified chitinase was 20 kDa, estimated by a sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and was confirmed by activity staining with Calcofluor White M2R. Chitinase was optimally active at pH of 5.0 and at $30^{\circ}C$. The enzyme was stable from pH 4 to 8, and up to $40^{\circ}C$. Among the metals and inhibitors that were tested, the $Hg^+$, $Hg^{2+}$, and p-chloromercuribenzoic acid completely inhibited the enzyme activity. The chitinase activity was high on colloidal chitin, chitotriose, and chitooligosaccharide. The purified chitinase showed antifungal activity against Botrytis cinerea, and lysozyme activity against the cell wall of Botrytis cinerea.

• Food Science and Biotechnology
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• 제17권5호
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• pp.904-911
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• 2008

Covalent cross-links between a number of proteins and peptides explain why transglutaminase may be widely used by food processing industries. The objective of this work was optimization of the fermentation process to produce transglutaminase from a new microbial source, the Streptomyces sp. P20. The strategy adopted to modify the usual literature media was: (1) fractional factorial design (FFD) to elucidate the key medium ingredients, (2) central composite design (CCD) to optimise the concentration of the key components. Optimization of the medium resulted in not only an 86% increase in microbial transglutaminase activity as compared to the media cited in the literature, but also a reduction in the production cost. Optimal fermentation conditions - namely temperature and agitation rate - were also studied, using CCD methodology. Usual conditions of $30^{\circ}C$ and 100 rpm were within the optimal area. All other parameters for enzyme production were experimentally proven to be optimum fermentation conditions.

• 한국미생물·생명공학회지
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• 제17권5호
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• pp.529-532
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• 1989

A strain of Streptomyces sp. (YS-221-B) extracellularly produced an inhibitory substance for $\alpha$-D-Glucosidase. The substance was purified 96-fold from culture filtrate by dialysis, heat treatment, adsorption on active carbon, Bio-Gel P-10 and Sephadex G-75 column chromatography with yield of 9.2%. The substance was stable in pH range from 7.0 to 11.0 at 37$^{\circ}C$, and a treatment at 10$0^{\circ}C$ for 20 min diminished only 15% of the original activity. The inhibitor was not inactivated by the treatment of $\alpha$-, $\beta$-amylases, glucoamylases, trypsin and chymotrypsin but inactivated by pyoteases from Streptomyces griseus and Tritirachium album.