• KSBB Journal
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• 제11권3호
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• pp.311-316
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• 1996

Polyethylene glycolCPEG)의 재조합 효모 배양 에서의 세포성장과 glucoamylase 생산에 대한 영향에 대하여 조사하였다. PEG 첨가에 의하여 세포성 장은 영향을 받지 않았으나 재조합 glucoamylase의 생산은 증가되었다. 최척의 PEG 분자량은 6000이었으며 최척의 농도는 1g/L이었다. 이러한 최척의 값을 이용하여 PEG 첨가배지에서 첨가하지 않은 배지보다 약 23%의 세포외 glucoamylase 활성의 증가를 보였다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XII)
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• pp.233-235
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• 2003

본 연구에서는 산업적으로 중요성이 날로 증가하고 있는 PLC의 대량 생산을 위해서 B. cereus ATCC10987에서 분리된 PLC 유전자를 $pPICZ{\alpha}$ C에 삽입한 P. pastoris system을 개발하여 extracellular PLC를 생산하였다. 또한, 여러 조건에서 B. cereus와 P. pastoris에서 생산된 extracellular PLC의 활성도를 측정하여 특성을 살펴보았다.

• 한국미생물·생명공학회지
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• 제24권6호
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• pp.712-716
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• 1996

The effects of non-ionic surfactants (Triton X-100 and Tween 80) on cloned glucoamylase production and secretion in recombinant Saccharomyces cerevisiae culture were studied. Even though the extracellular glucoamylase activity was increased by addition of Tween 80 due to the increase of the cell mass, Tween 80 did not play a role in the increase of glucoamylase secretion. On the addition of Triton X-100 addition, the secretion efficiency was increased while the cell growth was inhibited. Triton X-100 was added to the culture broth after 24 hr of culture to minimize the inhibition of the cell growth, and consequently the glucoamylase activity in the culture broth was increased by 12%.

• Journal of Microbiology and Biotechnology
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• 제19권9호
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• pp.966-971
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• 2009

Peroxidase from Coprinus cinereus (CiP) has attracted attention for its high specific activity and broad substrate spectrum compared with other peroxidases. In this study, the functional expression of this peroxidase was successfully achieved in the methylotrophic yeast Pichia pastoris. The expression level of CiP was increased by varying the microbial hosts and the expression promoters. Since a signal sequence, such as the alpha mating factor of Saccharomyces cerevisiae, was placed preceding the cDNA of the CiP coding gene, expressed recombinant CiP (rCiP) was secreted into the culture broth. The Mut Pichia pastoris host showed a 3-fold higher peroxidase activity, as well as 2-fold higher growth rate, compared with the $Mut^s $ Pichia pastoris host. Furthermore, the AOX1 promoter facilitated a 5-fold higher expression of rCiP than did the GAP promoter.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.688-691
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• 2000

Ferritin, an iron-storage protein, is found in bacteria and some animal tissues such as liver, spleen, and bone marrow. It is more effective and causes less side reactions than the traditional ferrous sulfate, and thus has been used primarily to treat iron deficiency in pregnancy anaemia. Currently, the ferritin extracted from the bovine and equine spleens are sold as a commercial product. Its market is estimated as several hundreds of million US dollars. However, because of the recent warnings against the viral diseases of animal origins such as mad cow disease, a safer ferritin is sought after. Our research team has successfully developed a production process for recombinant human ferritin. Its expression titer from yeast is high enough to be economically viable, and its particle formation characteristics are as effective as well.

• 약학회지
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• 제34권3호
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• pp.171-179
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• 1990

The recombinant gamma-interferon (LBD-001) which was produced by yeast as host system was investigated on the pharmacological activities. This gamma-interferon exhibited potent inhibitory effect on adjuvant induced arthritis, but no effect on carrageenin induced paw edema in rats. It did not show any sedative, anticonvulsive, analgesic and hypothermic activities in animals. It also had no influences on isolated tracheal muscle and ileum of guinea pig, isolated uterus and fundus strip of rats, and on blood pressure and respiration in situ experiments of rabbits.

• Toxicological Research
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• 제13권1_2호
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• pp.167-173
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• 1997

LBD-001, a recombinant human interferon $\gamma$ produced by genetically engineered yeast as a host system, was intravenously administered to pregnant female rabbits (New Zealand White strain) from day 6 to 18 of gestation at dose levels of $0.35 \times 10^6$, $0. 69 \times 10^6$, and $1.38 \times 10^6$ I.U./kg/day. Hydrocortisone sodium succinate (0.3 mg/kg/day) was also given in the same way. Teratological effects of the test agents on the organogenesis of fetuses and the development of offsprings (F1 rabbits) were investigated. The results were as followings: (1) No significant changes by the treatment of LBD-001 or hydrocortisone sodium succinate were observed in the body weights, the food and water consumption, the lactating or nurshing behaviors, and the autopsy of the pregnant rabbits. (2) No significant changes in the resorption rate, the fetal organogenesis, and the normal develpoment of offsprings (F1) by the treatment of LBD-001 or hydrocortisone sodium succinate were detected. The results show that LBD-001 at the dose of $1.38 \times 10^6$ I.U./kg/day or less and hydrocortisone sodium succinate at the dose of 0.3 mg/kg/day are neither teratogenic in the organogensis of the fetuses and the development of the offsprings (F1) nor toxic to the mother rabbits.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권3호
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• pp.242-247
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• 2005

Caseinomacropeptide (CMP) is a glycopeptide of 64 amino acid residues derived from the C-terminal of mammalian milk K-casein. Recently, human CMP (hCMP) was produced from the recombinant yeast Saccharomyces cerevisiae. In this study, the antiobesity activity of the recombinant hCMP (rhCMP) was investigated in vivo using Sprague-Dawley rats. The rhCMP did not affect the rats fed with a normal fat diet (fat content, $5.0\%$), but decreased the body weight gain of the rats fed with a high fat diet (fat content, $20\%$) by up to $19\%$. Autopsies revealed that the weights of the liver, kidney and adipose tissues decreased when the rats were given the rhCMP, which also reduced the lipid concentrations in the plasma and liver, but enhanced the fecal excretion of lipids. These results suggest that rhCMP prevent the accumulation of lipid by stimulating its fecal excretion, so could be used as a food supplement to alleviate the obesity problem caused by a high fat diet.

• 한국미생물·생명공학회지
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• 제23권4호
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• pp.454-460
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• 1995

Acetylxylan esterase II was produced by Escherichia coli HB101 harboring the recombinant plasmid pKMG7 which contained the estII gene of Bacillus stearothermophilus. Optimal medium for the production of the acetylxylan esterase by E. coli HB101/pKMG7 was determined to contain 0.5% galactose, 1% yeast extract and 1% NaCl. The enzyme produced was purified to homogeneity using a combination of 20-50% ammonium sulfate precipitation, DEAE-Sepharose CL-6B chromatography and Sephacryl S-200 gel filtration. The temperature and pH optimum of the esterase were 45$\circ$C and pH 6, respectively. The essential amino acids for the esterase activity were found to be methionine, serine, and cysteine. Molecular weight of the esterase was determined to be 28 kDa by SDS-polyacrylamide gel electrophoresis, and 120 kDa by gel filtration. This suggests that the functional enzyme is a homomeric tetramer. The esterase had an isoelectric point of pH 3.4. The N-terminal amino acid sequence of the enzyme was Ala-Leu-Phe-Glu-Ser-Arg-Phe-Phe-Ser-Glu-Val-Leu-Gly-Leu.

• 한국미생물·생명공학회지
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• 제46권1호
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• pp.45-50
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• 2018

The chitosanase gene (btbchito) of Bacillus thuringiensis BMB171 was cloned and heterologously expressed in the yeast Pichia pastoris. After purification, about 300 mg of recombinant chitosanase was obtained from the 1-1 culture medium with a specific activity of 240 units/mg. Results determined by the combined use of thin layer chromatography (TLC) and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) showed that the chitooligosaccharides (COSs) obtained by chitosan (N-deacetylated by 70%, 80%, and 90%) hydrolysis by rBTBCHITO were comprised of oligomers, with degrees of polymerization (DP) mainly ranging from trimers to heptamers; high molecular weight chitopentaose, chitohexaose, and chitoheptaose were also produced. Hydrolysis products was also deduced using MS since the COSs (n) are complex oligosaccharides with various acetyl groups from one to two, so the non-acetyl COSs (GlcN)n and COSs with more acetyls (> 2) were not detected. The employment of this method in the production of high molecular weight COSs may be useful for various industrial and biological applications, and the activity of chitosanase has great significance in research and other applications.