• 미생물학회지
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• 제15권3호
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• pp.131-138
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• 1977

The effects of various nitrogen soruces on the expression of nif gene were investigated using nif-lac fusants of Klebsiella pneumoniae. K. pneumoniae UK 2979 was infected with Mudl lysate prepared by heat induction of K. pneumoniae UK 4482. About 80 nif-lac fusants were greatly repressed. Amino acids, such as serine, glutamine and asparagine, were found to support the growth of K. pneumoniae M5al quite well, and showed a repressive effect on .betha.-galactosidase activities of nif-lac fusants LX-9 and LX-22 in NFHM. Glutamic acid, histidine and arginine rendered poor growth but high activities of .betha.-galactosidase. Good cell growth and high enzyme activity were observed when complex nitrogen sources, such as casitone, proteose pepone, were employed. .betha.-Galactosidase activities of LX-9 and LX-22 in nitrogen free minimal medium increased sharply within first 4 hours.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2000년도 추계학술발표대회
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• pp.85-91
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• 2000

Aspergillus oryzae is a filamentous fungus classified in the group Aspergillaceae Ascomycetes. It is an important microorganism for industrial production of enzymes and fermented food productions. It secrets large quantities of proteins or enzymes into the culture medium which makes this organism appealing for the production of heterologous proteins. Recently Electric field-mediated transformation method, electroporation, has been applied to fungal transformation. In this study, fungal transformation was carried out by bypassing the protoplast isolation step, decreasing the culturing time and non-protoplast transformation for the increment of transformation efficiency. Transformants were obtained with electroporation in optimal condition 2,500 voltage, 1,540 ohm and 0.50 capacitance. More than 1,000 transform ants were obtained with 6-10 hrs cultured mycelia without enzyme treatment, called non-protoplast transformation.

• 한국균학회지
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• 제45권3호
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• pp.212-223
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• 2017

비병원성 야생효모들로부터 새로운 항염물질을 생산하고자 우리나라 주요 섬과 산에서 분리, 동정한 야생 효모들 중 비병원성 효모들의 무세포 추출물들을 제조하여 이들의 nitric oxide (NO) 생성 저해활성을 측정하였다. 182 균주 중 Metschnikowia reukaufii SY20-7, Rhodotorula ingeniosa SY1-1, Yarrowia lipolytica SY51-1, 51-3, Meyerozyma guilliermondii YJ34-2, Rhodotorula graminis YJ36-1, Rhodotorula nothofagi YJ1-1, YJ22-2, Metschnikowia koreensis UL32-1, Sporobolomyces carnicolor UL32-3 등 10 균주들의 무세포 추출물들이 30% 이상의 NO 생성 저해활성을 보였다. 이들 중 유포자효모들에서는 Rhodotorula graminis YJ36-1가 가장 높은 57.4%의 NO 생성 저해활성을 보였고 무포자효모들에서는 Meyerozyma guilliermondii YJ34-2가 47.0%로 가장높아 항염물질생산 우수효모로 최종 선발하였다. 선발된 야생효모들의 미생물학적 특성을 조사한 결과 Rhodotorula graminis YJ36-1 균주는 자낭포자와 위균사를 형성하였고 $25^{\circ}C$에서 잘 생육하였으며 Meyerozyma guilliermondii YJ34-2는 자낭포자와 위균사를 형성하지 않았고 $30^{\circ}C$, 5%의 NaCl 함유 YPD 배지에서도 잘 생육하였다. 또한, 두 효모 모두 pH 4.0~8.0에서 생육하였고 YM, PD, YPD, 비타민 무함유 배지 등에서 잘 생육하였다.

• Journal of Microbiology and Biotechnology
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• 제22권11호
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• pp.1518-1522
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• 2012

Leuconostoc mesenteroides is a heterofermentative Grampositive bacterium that plays key roles in fermentation of foods such as kimchi, sauerkraut, and milk, leading to the production of various organic acids and aromatic compounds. To study the microbiological and genomic characteristics of L. mesenteroides, we have developed a new chemically defined minimal medium by using the single omission technique. During the exponential cell growth, this species required glutamine, methionine, valine, and nicotinic acid as essential nutrients and 8 amino acids (arginine, cysteine, histidine, leucine, phenylalanine, proline, threonine, and tryptophan), 5 vitamins (ascorbic acid, folic acid, inosine, calcium panthothenate, and thiamine), and others (manganese, magnesium, adenine, uracil, and Tween 80) as supplemental nutrients. This medium is useful to study the metabolic characteristics of L. mesenteroides and to explain its role in food fermentation.

• 미생물학회지
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• 제37권1호
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• pp.21-27
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• 2001

Bacillus anthracis Sterne 34F$_2$균주로부터 PA를 생산하기 위해 RM배지를 변형하였다. NaHCO$_3$를 8 g/l에서 10 g/l로, glucose를 5 g/l로 첨가하여 새로운 배지조성에서 탄저균을 배양한 후, 배양액을 hydroxyapatite를 이용하여 농축하였다. 농축된 조단백질을 hydroxyapatite column chromatography, DEAE-Sepharose CL-4B column chromatography 및 Toyo-pearl gel filtration chromatography를 사용하여 PA를 정제하였다. 변형된 RM 배지를 사용해 얻은 PA 양은 8.6 mg/l 이었다.

• 미생물학회지
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• 제29권3호
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• pp.149-154
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• 1991

Escherichia coli/Corynebacterium glutamicum shuttle vectors, pECCG1 and pECCG2 were constructed by joining a 3.00 kb cryptic plasmid pCB 1 from C. glutamicum and a 3.94 kb plasmid pACYC 177 from E. coli. By trimming unessential parts and introducing mulitiple cloning site into the plasmid pECCG 1, a plasmid pECCG122(5.1kb) was constructed. All the shuttle vectors were stably maintained in C. glutamicum up to about 40 generations irrespective of kanamycin addition in the medium. Threonine operon (homoserine dehydrogenase/homoserine kinase) and dapA gene (dihydrodipicolinate synthetase) of C. glutamicum were cloned into the plasmid pECCG122, and the resultant plasmids were designated pTN31 and pDHDP19, respectively. They were used to study the effect of cloned foreign gene on the stability of the plasmid pECCG122. Plasmids pTN31 and pDHDP19 were segregated rapidly from C. glutamicum when cultured in the medium without kanamycin. In medium with $50\mu${\g/ml} of kanamycin, their segregation rates were much slower than those in medium without kanamycin, but the danamycin addition didn't guarantee the complete maintenance of the plasmids in C. glutamicum.

• 한국균학회지
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• 제50권1호
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• pp.65-73
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• 2022

본 연구는 남해안 해운대와 인근 몽돌해수욕장 주변의 야생 효모 종 분포특성을 알아보기위해 이들 지역 주변의 물과 모래, 토양 등 70점의 시료들로부터 일반 효모와 호알칼리성 균주 등 모두 37종, 41균주의 야생 효모들을 분리하였다. 이들 야생 효모들 중 Cys. insectorum HUD16-3 (JSLKSS-002)와 M. citriensis HUD12-5 (JSL-KSS-001)등 두 균주들이 국내 보고되지 않은 미기록 효모들로 선별되었고 필자 등이 전라북도 장선천 주변 토양에서 분리하여 국내 미기록 균주로 선별한 Cys. lysinophilum JSC 52-2 (JSL-GGU-019)와 대전광역시 장태산 호수 주변에서 분리하여 선별한 C. takata NMD11-1 (JSL-GGU-017), C. panamensis ASG58M-2 (JSL-GGU-018)등 5종의 미기록 야생 효모들의 균학적 특성을 조사하였다. 이들 미기록 효모들은 모두 난형으로 출아에 의해 영양 증식을 하였고 포자와의 균사를 형성하지 않았다. 미기록 효모 모두 vitamin-free배지에서도 생육하였고 M. citriensis HUD12-5균주는 50% 포도당을 함유한 YPD배지에서 생육하는 강한 내당성을 보였고 Cys. insectorum HUD16-3과 M. citriensis HUD12-5균주들은 15% NaCl을 함유한 YPD배지에서도 생육이 비교적 양호한 호염성균이었다 또한, 미기록 효모들 모두 포도당과 fructose, sucrose, 전분 등을 자화시켰고 특히Cys. lysinophilum JSC 52-2등 3균주들은 lactose를 자화시켰다.

• 미생물학회지
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• 제5권2호
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• pp.61-68
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• 1967

In the process of the incorporation of orthophsphate into protein and other cell constituents, the role of inorganic polyphosphate and RNA-polyphosphate complex and the correlation between them were pursued by analyzing the contents of $^{32}P$ and total P in various fractions of Chlorella cells, which had been uniformly labeled with $^{32}P$ before the inoculation in a normal "cold" medium or P-free medium during the culture. The effects of ionizing radiation and various micronutritional-element deficiencies on the phosphate incorporation into, and biosynthesis of, protein and other introgenus compounds in the cells were also observed. When the uniformly $^{32}P$-labeled algae were grown in a normal "cold" medium the contents of $^{32}$ P in the fractions of protein, DNA and RNA-polyphosphate complex increased, but those in the fraction of acid-insoluble polyphosphate decreased. On the other hand, amount of $^{32}P$in the fraction of RNA was almost unchanged in spite of rapid increase of the total P. In the growing period of $^{32}P$-labeled algae in a P-free medium, amounts of $^{32}P$ in the fractions of DNA, protein and lipid increased, while those in the fractions of RNA-polyphosphate and inorganic polyphosphates decreased. When the algal cells were irradiated with about 70, 000r of gamma-rays before the inoculation in the medium, amounts of phosphate in the fractions of DNA, RNA, nucleotides and protein decreased during the culture, compared with those of the control. However, the phosphate content in the fraction of acid-insoluble polyphosphate of the irradiated cells increased than those of the control. In the growing period of the algae in a Mo-free, medium, amounts of acid-soluble total phosphate and nucleotides of the cells increased, while the amounts of residual protein and RNA decresed compared with those of the normal cells. Amounts of alkali-labile protein and phospholipid of the cells grown in a B-free medium decreased, whereas amount of phosphate in acid-soluble fraction increased compared with the control. In general, the contents of protein and RNA in each microelement deficient cells decreased more or less, compared with those in the normal cells.in the normal cells.

• 미생물학회지
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• 제33권1호
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• pp.27-30
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• 1997

Coprinus congregatus를 pH 4.2로 낮춘 YpSs 액체배지에 접종할 경우 세포막연관효소인 laccase가 배양 1일만에 상등액으로 대량 생성분비된다. 분비된 효소는 매우 빠르게 효소력의 감소를 보이며 전기영동상의 이동변화가 있다. 이와 같이 변화된 전기영동상을 보이는 효소단백질을 분광광도계로 분석할 경우 정제된 효소단백질과는 다른 분광 스펙트럼을 보인다.

• Journal of Microbiology
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• 제33권2호
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• pp.146-148
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• 1995

Coprinus congregatus has a membrane-associated laccase which is not secreted into culture media. A mutant monokaryon obtained, by U. V. irradiation followed by protoplast generation and regeneration method, was successfully isolated. When the mutant was grown on a agar plate or in a liquid medium, it secreted laccase while the wild type did not under the same growth conditions. The laccase of the mutant was compared with that of wild type did not under the same growth conditions. The laccase of the mutant was compared with that of wild type of native PAGE analysis, and showed identical mobility.