• 한국미생물·생명공학회지
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• 제24권2호
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• pp.166-172
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• 1996

It is well known that actinomycetes would be useful for screening of biologically active compounds. Not only to isolate diverse actinomycete strains but to ferment those strains effectively would be important. Seven hundred and forty six strains were isolated from Cheju province, 216 strains were from Chungnam province, 158 strains were from the natural caves at Chungbuk and Kangwon provinces and 202 strains were from Chungwon area at Chungbuk province. All of these 1,322 strains were fermented on a small scale using two different media and tested for their antimicrobial activities against four bacterial strains and one yeast strain. As the result, 12.3% of those isolates were active against Staphylococcus aureus KCTC 1916, 7.6% were Staphylococcus aureus KCTC 1928, 3.9% were Escherichia coli KCTC 1924, 3.0% were Candida albicans KCTC 1940, and 2.2% were Salmonella typhimurium KCTC 1926. About 40% of those isolates showed antimicrobial activities at both two media but the others showed at either one. According to the genus of isolated strains, Streptomyces and Micromonospora showed activities with higher frequencies than others.

• 한국미생물·생명공학회지
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• 제22권6호
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• pp.685-691
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• 1994

The biodegradation of aromatic compounds by mixed and monoculture was investigated in an artificial wastewater containing 500 mg/l of benzene(B), phenol(P), and toluene(T) in various combinations. None of three strains utilized P-xylene(X) as a carbon source, but they grew well on p-xylene in mixtures with benzene and toluene. In the mixed culture on mixed substrate, the length of lag phase was different depending on the nature of mixture. Cell growths of Flavobac- terium sp. BEN2 and Acinetobacter sp. GEM63 were inhibited in the presence of a 500 mg/l of phenol. When the mixed culture of three strains was cultured in a bench-scale reactor containing artificial wastewater, each of benzene, phenol, and toluene was not detected at 30 hrs, 50 hrs, and 12 hrs after incubation in the treatment. The removal rates of COD$_{t}$(total COD) and COD$_{s}$,(soluble COD) of upper phase after centrifugation during early 50 hrs were ca. 80% and ca. 93.8%, respectively.

• 생명과학회지
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• 제22권8호
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• pp.1132-1136
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• 2012

많은 종류의 세포스트레스는 unfolded protein response (UPR)관련인자의 유전자발현을 조절한다. 본 연구결과 부동스트레스(immobilization stress)는 세포의 소포체스트레스(ER stress)와 관련된 유전자발현의 변화를 유도한다; Heart, spleen, thymus, kidney, testis에서는 유전자발현 변화가 없었지만 adrenal gland, liver, lung에서는 유의할만한 상승변화가 있었다. 그러나 muscle에서는 다른 것들과 대조적으로 발현이 감소되었다. 이 결과는 부동스트레스도 다른 종류의 세포스트레스와 같이 세포수준에서 UPR을 조절할 수 있다는 최초의 보고이다.

• 생명과학회지
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• 제9권5호
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• pp.518-524
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• 1999

Timing of oviposition, nuclear maturation of oocytes, egg-sperm contact and brooding were observed in the giant fresh-water prawn Macrobrachium rosenbergii reared in the laboratory. When a pre-spawning molted female was transferred to the male, the female oviposited commonly at 5 to 10 hr after mating. The first polar body were extruded within 2-3 min after spawning. The egg chromosome progressed to release second polar body by 30 min and mitotic nuclear division occurred in 8 hr after spawning. Thumbtack-shaped spermatozoa were seen peneterating egg membrane with their spike directed forward. Transformation of spermatozoa and fertilization membrane could not be observed by light microscopy. The elapsed hours from oviposition to the end of brooding wee taken in 5-7 hr. Brood size for female 9 cm and 18 cm in body length was estimated to be 10,000~15,000 and 100,000 eggs, respectively and is proportional to the total length of the berried females. The ovigerous females reared at chlorinity of 2.21~4.25$\textperthousand$Cl. showed a normal egg development up to hatching.

• 생명과학회지
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• 제9권5호
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• pp.548-555
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• 1999

Long-term effects of Ganoderma lucidum (GL) on memory and oxidative stress of senescence-accelerated mice (SAM) were investigated. Senescence-resistant (R1) and prone (P8) strains of SAM were fed GL diets, premixed with low (20 mg/kg/day, T1) or high (200 mg/kg/day, T2) levels of GL powder for 9 months starting from young (3 months of age) or for 5 months starting from old (7 months of age). After the final feeding at 12 months of age, all animals were subjected to passive avoidance test for the evaluation of memory function. In addition, the changes in hepatic thiobarbituric acid-reactive substance (TBARS) and glutathione were analyzed. SAMP8 fed GL diets from old age (7 months) exhibited the improvement of memory, although GL rather inhibited the memory function of both SAMR1 and SAMP8 mice fed diets from young (3 months of age). Hepatic TBARS contents were decreased in SAMP8 fed high GL diet for 9 months and in SAMR1 fed low GL diet for 5 months. Hepatic glutathione content was also remarkably increased in SAMR1 following both feeding periods, and less extent in SAMP8 fed diet for 5 months of age. Taken together, it is proposed that GL extracts may play an anti-aging role through antioxidant action, and thereby may improve the senescence-related memory dysfunction.

• 생명과학회지
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• 제24권1호
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• pp.81-85
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• 2014

산업폐수로부터 분리한 Pseudomonas sp. BCNU 106은 다양한 유기용매를 이용하여 인돌로부터 인디고를 합성할 수 있다. BCNU 106은 높은 수준의 인돌과 다량의 p-xylene, propylbenzene 그리고 mesitylene의 존재 하에서 효과적으로 인디고를 생산했다. 본 연구에서 인디고의 최대수율 조건은 20% (v/w)의 p-xylene과 4 g/l의 인돌인 것으로 확인되었다. 이러한 조건에서 인디고의 수율과 인돌의 전환효율은 각각 315.5 mg/l와 97%로 조사되었다. 그 결과 Pseudomonas sp. BCNU 106은 산업적으로 중요한 인디고 생산을 위한 잠재적인 균주가 될 것으로 판단된다.

• 생명과학회지
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• 제17권7호통권87호
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• pp.1023-1025
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• 2007

Ajuba is a number of proteins containing cytosolic LIM domain. Its function may provide a new pathway whereby cell-cell adhesive events are transmitted to the nucleus to regulate cell proliferation and differentiation decisions. Here, Ajuba gene expression was investigated its molecular properties associated with endoplasmic reticulum (ER) stresses (tunicamycin, DTT, A23187 and BFA) which induced remarkable ex-pression of Ajuba mRNA. The mRNA half life of Ajuba was also determined, its half life of Ajuba mRNA in FRTL-5 cells was approximately 2 hr after the initial translation. Although the obvious bioligical function of Ajuba is not clear, on the base of the results, Ajuba gene expression is deeply associated with ER stresses.

• 생명과학회지
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• 제23권5호
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• pp.669-675
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• 2013

본 연구에서는 Monascus sp. MK2가 생산하는 홍국색소의 안정성에 대하여 조사한 결과에서 광 안정성에서는 암 조건>자외선>실내(형광)>태양광 조건 순서로 안정하였으며, 온도에 대한 안정성은 온도가 증가하고 저장시간에 길어짐에 따라 홍국색소의 감소율 또한 비례적으로 증가하였고, pH에 대한 안정성은 전체적인 pH 영역에서 비교적 안정하였으며, 유기산 첨가에 대한 홍국색소의 안정성은 높은 것으로 생각되며, 합성 항산화제와 천연물 추출물 첨가시에는 안정성이 증대되는 것으로 조사되었다.

• 한국미생물·생명공학회지
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• 제30권1호
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• pp.46-50
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• 2002

일반 상법으로 제조되는 코오지, 즉 밀 또는 대두에 A. oryzae만으로 제조하는 코오지에 Cordyceps sp.를 첨가하여 코오지의 품질에 미치는 영향을 조사하였다. A. oryzae만으로 제조하는 코오지에 Cordyceps sp.를 일정량 혼합 첨가하여 제국하여 생균수 및 포자수를 측정한 결과 48시간까지 급격히 증가했다. 이후 생균수 및 곰팡이의 포자수의 유의할만한 변화를 볼 수 없어 제국시간을 48시간 전후로 조정하는 것이 바람직한 것으로 나타났다. 또한 amylase 및 protease등의 효소역가를 측정한 결과 Cordyceps sp.를 첨가한 코오지가 Cordyceps sp.를 첨가하지 않은 코오지보다 효소역가가 높은 것으로 나타났다. 제국이 끝난 코오지에 대하여 맛, 향 및 색깔에 대하여 관능검사를 실시한 결과 A. oryzae와 Cordyceps sp.를 각각 0.5％(w/w)를 혼합 참가한 것이 더 좋게 나타났다.

• 한국미생물·생명공학회지
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• 제23권6호
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• pp.678-686
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• 1995

SecY is a central component of the protein export machinery that mediate the translocation of secretory proteins across the plasma membrane of Escherichia coli. In order to study the mechanism of protein secretion in Streptomyces, we have done cloning and sequencing of the Streptomyces coelicolor secY gene by using polymerase chain reaction method. The nucleotide sequence of the gene for SecY from S. coelicolor showed over 58% identity to that of M. luteus. The deduced amino acid sequences were highly homologous to those of other known SecY polypeptides, all having the potential to form 10 transmembrane segments, and especially second, fifth, and tenth segments were particularly conserved, sharing greater than 75% identity with W. lute s SecY. We propose that the conserved membrane-spanning segments actively participate in protein export. In B. subtilis and E. coli, the secY gene is a part of the spc operon, is preceded by the gene coding for ribosomal protein L15, and is likety coupled transcriptionally and translationally to the upstream L15 gene. In the other hand, secY gene of S. coelicolor and M. luteus have its own promoter region, are coupled translationally with adk gene and pr sented in adk operon.