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논문검색은 역시 페이퍼서치

한국미생물·생명공학회지검색

Microbiology and Biotechnology Letters


  • - 주제 : 자연과학분야 > 생물
  • - 성격 : 학술지
  • - 간기: 계간
  • - 국내 등재 : KCI 등재
  • - 해외 등재 : - / SCOPUS
  • - ISSN : 1598-642x
  • - 간행물명 변경 사항 : 산업미생물학회지(~2001)→한국미생물·생명공학회지(2002~)
논문제목
수록 범위 : 40권 1호 (2012)

아가로오스 분해세균인 Pseudoalteromonas sp. GNUM08122 분리 및 동정

김성배 ( Sung Bae Kim ) , 장용근 ( Yong Keun Chang ) , 홍순광 ( Soon Kwang Hong ) , 김창준 ( Chang Joon Kim ) , 김유나 ( Yu Na Kim ) , 김무찬 ( Mu Chan Kim ) , 지원재 ( Won Jae Chi ) , 정연규 ( Yeon Kyu Jeong )
4,500
초록보기
Korea This study`s aim was to isolate microorganisms producing agarase with a high activity, with possible applications in improving the performance of the pretreatment processes for bioethanol production. Marine algaes were collected from the south coast of Korea, from which three kinds of microorganisms were isolated. After a 4-day culture of these strains at 25oC, crude enzymes were obtained from culture supernatant or cell-free extract by ammonium sulfate precipitation and membrane dialysis. Agarase activity was observed in these crude enzymes. Notably higher specific activity was observed in the crude enzyme obtained from the culture supernatant rather than that from the cell-free extract. This indicates that a secreted enzyme has a much greater activity than a cellular enzyme. Crude enzymes from the GNUM08122 strain were inferred to have α-agarase activity because release of p-nitrophenol was observed, possibly due to the cleavage of p-nitrophenyl-α-D-galactopyranoside. The 16S rRNA sequence of GNUM08122 showed a close relationship to Pseudoalteromonas issachenkonii KMM 3549 (99.8%) and Pseudoalteromonas tetraodonis IMA 14160 (99.7%), which led us to assign it to the genus Pseudoalteromonas. Biochemical and physiological study revealed that this strain can grow well at 40oC under a wide range of pH (pH 4~8) in high-salt conditions (10% NaCl).

방선균 항생제 고생산 산업균주를 기반으로 한 모델 폴리케타이드의 이종숙주 발현

김혜진 ( Hye Jin Kim ) , 이한나 ( Han Na Lee ) , 김응수 ( Eung Soo Kim )
4,500
초록보기
The Streptomyces peucetius OIM (Overproducing Industrial Mutant) strain is a recursively-mutated and optimally-screened strain used for the industrial production of polyketide antibiotics, such as doxorubicin (DXR). Using the S. peucetius OIM mutant strain as a surrogate host, a model minimal polyketide pathway for aloesaponarin II, an actinorhodin shunt product, was cloned in a high-copy conjugative plasmid, followed by functional pathway expression and quantitative metabolite analysis. The level of aloesaponarin II production was noted as being significantly higher in the OIM strain than in the wild-type S. peucetius, as well as in the regulatory network-stimulated S. coelicolor mutant strain. Moreover, the aloesaponarin II production level was seen to be even higher in a down-regulator wblAspe-deleted S. peucetius OIM strain, implying that the rationally-engineered S. peucetius OIM mutant strain could be used as an efficient surrogate host for the high expression of foreign polyketide pathways.
4,500
초록보기
A bacterial strain was isolated from homemade Cheongkookjang as a producer of the β-galactosidase, capable of hydrolyzing lactose to liberate galactose and glucose residues. The isolate YB-1105 has been identified as Bacillus licheniformis on the basis of its 16S rDNA sequence, morphology and biochemical properties. β- Galactosidase activity was detected in both the culture supernatant and the cell extract of B. licheniformis YB- 1105. The enzymes of both fractions demonstrated maximum activity for hydrolysis of para-nitrophenyl-β-Dgalactopyranoside (pNP-βGal) under identical reaction conditions of pH 6.5 and 50oC. However, β-galactosidase activity from the culture filtrate was affected more than that from the cell free extract at acidic pHs and high temperatures. The hydrolyzing activity of both β-galactosidases for pNP-βGal was dramatically decreased by the addition of low concentrations of galactose, but was only marginally decreased by high concentrations of glucose or mannose.

항진균성 물질을 생산하는 지의류 내생 곰팡이의 탐색

김은성 ( Eun Sung Kim ) , 최갑성 ( Kap Seong Choi ) , 최상기 ( Sang Ki Choi )
4,500
초록보기
To isolate a novel antifungal compound, we obtained 100 kinds of endolichenic fungi from Korean Lichen & Allied Bioresources Center and examined their antifungal capability. Three fungi Usnea rigidula (2326), Parmotrema pseudotinctorum (2202) and Myelochroa sp. (2292) showed high antifungal activity against Candida albicans when they grew in both liquid and solid media. We extracted the culture supernatants of these three fungi with chloroform and then with ethyl acetate. Chloroform fraction exhibited the highest antifungal activities when those fractions were examined for the growth inhibition of Candida albicans with disc diffusion method. The chloroform faction was on further analysis with C18 column chromatography to see whether the inhibitors are already known or not. Two peak fractions were collected from 4-day culture extract for Usnea rigidula and from 6-day culture extract for Parmotrema pseudotinctorum on the HPLC. A peak fraction from chloroform extracts of 4-day culture filtrate of Parmotrema pseudotinctorum showed higher antifungal activities against C. albicans and C. glabrata than another peak fraction. It appears that the antifungal materials are relatively nonpolar as usnic acid often found in lichenic fungi.

경작지토양에서 미생물제제가 미생물의 다양성과 고추의 생육에 미치는 영향

안창환 ( Chang Hwan An ) , 임종희 ( Jong Hui Lim ) , 김요환 ( Yo Hwan Kim ) , 정병권 ( Byung Kwon Jung ) , 김진원 ( Jin Won Kim ) , 김상달 ( Sang Dal Kim )
4,500
초록보기
We investigated the effects on soil microbial diversity and the growth promotion of red pepper resulting from inoculation with a microbial agent composed of Bacillus subtilis AH18, B. licheniformis K11 and Pseudomonas fluorescens 2112 in a red pepper farming field. Photosynthetic bacteria, Trichoderma spp., Azotobacter spp., Actinomycetes, nitrate oxidizing bacteria, nitrite oxidizing bacteria, nitrogen fixing bacteria, denitrifying bacteria, phosphate solubilizing bacteria, cellulase producing bacteria, and urease producing bacteria are all indicator microbes of healthy soil microbial diversity. The microbial diversity of the consortium microbial agent treated soil was seen to be 1.1 to 14 times greater than soils where other commercial agent treatments were used, the latter being the commercial agent AC-1, and chemical fertilizer. The yield of red pepper in the field with the treated consortium microbial agent was increased by more than 15% when compared to the other treatments. Overall, the microbial diversity of the red pepper farming field soil was improved by the consortium microbial agent, and the promotion of growth and subsequent yield of red pepper was higher than soils where the other treatments were utilized.

벼의 생엽절편을 이용한 병원균 억제물질의 대량 스크리닝 방법 개발

박샛별 ( Sait Byul Park ) , 이충환 ( Choong Hwan Lee ) , 김태종 ( Tae Jong Kim ) , 강린우 ( Lin Woo Kang ) , 이병무 ( Byoung Moo Lee ) , 김정구 ( Jeong Gu Kim )
1,000
초록보기
A new method for the high throughput screening of antagonistic substances against rice pathogens using rice leaf explants was developed. This method can be used to confirm the activities of any compound or mixture suppressing rice bacterial blight (BB) before field tests. Xanthomonas oryzae pv. oryzae (Xoo) culture medium was distributed in 96 well plates with equally sized explants and the active compounds were added to the wells. The strength suppressing BB was converted into an area percent of the lesion on the rice explants. The explants under BB suppressing activity remained uninfected maintaining their actual green color, while infected explants exhibited pale yellow-colored lesions. Based on the results, this method seems to be faster and easier, dose-dependent, and can be performed all-at-once with a small amount of unspecified compounds. This method also has the potential to be applied to inspection activities for the suppression of other waterborne crop diseases.

비타민나무 잎 추출물의 항균 활성 및 크림의 안정성

채교영 ( Kyo Young Chae ) , 김정은 ( Jung Eun Kim ) , 박수남 ( Soo Nam Park )
4,500
초록보기
In this study, we investigated the antibacterial activity and stability of a cream containing Hippophae rhamnoides leaf extract. The MIC values of ethyl acetate fraction from an H. rhamnoides leaf on Escherichia coli, Pityrosporum ovale, Propionibacterium acnes and Staphylococcus aureus were 0.5%, 0.25%, 0.25% and 0.06%, respectively. Stability evaluations, pH, viscosity and absorbance of the cream containing 0.25% ethyl acetate fraction of H. rhamnoides, were performed. The cream was measured under 4 different temperature conditions under sunlight at 2-week intervals for 12 weeks. The viscosity and pH were measured by a comparison of the experimental cream with a similar control cream. The H. rhamnoides extract was found to have contributed to the stability of the emulsion product via a protective effect in maintaining the viscosity of the cream against sunlight. The absorbance variations of the experimental cream at 270 nm were, under sunlight; 45oC, 37oC, 25oC, and 4oC. In addition, any change in color or smell was not observed through the 12 weeks of the experimental period. These results indicated that the cream containing 0.25% ethyl acetate fraction of H. rhamnoides leaf extract was stable. Accordingly, this suggests that further study is needed to provide additional information for manufacturers, who are seeking the application of the extract to improve anti-oxidant and antibacterial activities and the stability of cosmetic products.
초록보기
The Wnt/β-catenin signaling pathway regulates diverse developmental processes and adult tissue homeostasis. Inappropriate regulation of this pathway has been associated with human diseases, such as cancers, osteoporosis, and Alzheimer`s disease. Using a cell-based chemical screening with natural compounds, we discovered silybin, a plant flavonoid isolated from the Silybum marianum, which activated the Wnt/β-catenin signaling pathway in a synergy with Wnt3a-conditioned medium (Wnt3a-CM). In the presence of Wnt3a-CM, silybin up-regulated β-catenin response transcription (CRT) in HEK293-FL reporter cells and 3T3-L1 preadipocytes through stabilization of intracellular β-catenin protein. Silybin and Wnt3a-CM synergistically reduced expression of important adipocyte marker genes including peroxisome-proliferator-activated receptorγ (PPARγ) and CAATT enhancer-binding protein α (C/EBPα) in 3T3-L1 preadipocytes, accompanied by the activation of Wnt/β-catenin signaling pathway. Taken together, our findings indicate that silybin is a small-molecule synergist of the Wnt/β-catenin signaling pathway and can be used as a controllable reagent for investigating biological processes that involve the Wnt/β-catenin signaling pathway.

메주에서 분리한 Bacillus polyfermenticus CJ6가 생산하는 항진균 물질의 분리 및 특성

양은주 ( Eun Ju Yang ) , 마승진 ( Seung Jin Ma ) , 장해춘 ( Hae Choon Chang )
4,500
초록보기
Antifungal compounds from Bacillus polyfermenticus CJ6 were purified using SPE, preparative HPLC, and reverse phase-HPLC. Antifungal compounds from B. polyfermenticus CJ6 were separated into three fractions (8, B, C) using preparative HPLC. LC/MS analysis of antifungal peaks suggested that B. polyfermenticus CJ6 produces lipopeptides; two kinds of iturin A (C14, C15), three kinds of surfactins (C13, C14, C15), four kinds of fengycin A (C14, C15, C16, C17) and two kinds fengycin B (C16, C17). The antifungal activity of fraction 8, which was presumed as inturin A, was found to be stable after the pH, heat or proteolytic enzyme treatment, but it was unstable at 50-70oC for 24 hr. The antifungal activity of fraction B, which presumed as surfactins and fengycin A, was found to be stable after the heat treatment, but it was unstable in the pH 3.0 and after the protease (type I) or α-chymotrypsin treatment. The antifungal activity of fraction C, which was presumed as fengycin A and B, was found to be stable in the pH 3.0-9.0 range and the heat treatment, but it was unstable with the treatment of protease (type I). The amino acid composition of the purified peaks 8-1 and 8-2 were Asx, Tyr, Gln, Pro, and Ser in a molar ratio of 3:1:1:1:1, which showed the same amino acid composition as iturin. From these results, we confirmed that antifungal compounds from B. polyfermenticus CJ6 most likely belonged to iturin A as well as surfactins and fengycins. As lipopeptides are known to act in a synergistic manner, the antifungal compounds from B. polyfermenticus CJ6 might have potential uses in biotechnology and biopharmaceutical applications.

Antifungal Property of Microorganisms against Korea Oak Wilt Pathogen, Raffaelea quercus-mongolicae

( Sang Hyun Lee ) , ( Seung Kyu Lee ) , ( Jae Young Kim ) , ( Chong Kyu Lee ) , ( Kyung Hee Kim ) , ( Yong Sub Yi )
1,000
초록보기
Five strains out of 200 candidate strains (SG 1-9, 1-12, SG 2-8, 2-10, and 2-17) were selected to determine their antifungal activity against Raffaelea quercus-mongolicae. The 16S rDNA sequences of the five strains were determined by sequencing analysis and analyzed by the homology of the blast program at NCBI. The homology search showed that SG 1-9 and 1-12 had a 98% homology with Streptomyces cinnamoneus and 98% homology with Burkholderia cepacia, while SG 2-8, 2-10, and 2-17 had a 99% homology with Streptomyces fradiae, a 97% homology with Staphylococcus epidermidis, and a 99% homology with Staphylococcus epidermidis. Out of the five selected strains, organic extract and protein extracts of SG2-17 strain broth were employed to determine antifungal activity against Raffaelea quercus-mongolicae. The organic extract exhibited antifungal activity, but the protein extracts did not demonstrate such an activity. Three organic solvents, butanol, benzene, and ethyl acetate, were also used for determination of antifungal activities. The activity measurements revealed that benzene extract possessed the greatest inhibitory effect on the growth of Raffaelea quercus-mongolicae, with the next highest being butanol extract, and ethyl acetate extract being the lowest.
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