• Journal of Dairy Science and Biotechnology
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• 제23권1호
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• pp.1-8
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• 2005

우리나라 재래종인 한우의 초유로부터 lactoferrin(Lf)을 분리하기 위해서 batch extraction, ion exchange chromatography, gel filtration chromatography, affinity chromatography 등의 정제과정을 실시하였다. 각 정제 단계에 의해 한우 Lf과 결합되어 있던 여러 물질들이 제거되었으며 한우 초유 1 liter에서 정제과정을 통하여 회수한 Lf의 양은 65mg로 회수율이 29.4%였다. SDS-PAGE와 HPLC를 이용해 확인한 결과, 정제 단계를 거침에 따라 순도가 높아지는 것 알 수 있었다. 정제된 한우 Lf은 분자량이 81 kDa 이고 등전점은 pI 9였으며, 철 함량이 0.56mg/g으로 철 포화도는 약 40.6%로 측정되었다. 한우 Lf과 젖소 Lf은 아미노산 조성과 ${\alpha}$-helix 함량에서 서로 다르게 나타났다. E. coli O111에 대한 항균성은 젖소 Lf이 한우 Lf 보다 높았으며, 최소저해농도(MIC)는 젖소 Lf이 1.5mg/ml, 한우 Lf은 2.75mg/ml로 젖소 Lf의 항균 활성이 더 높은 것으로 나타났다.

• 한국어병학회지
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• 제25권3호
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• pp.165-172
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• 2012

Vibrio alginolyticus (V. alginolyticus) 는 우리나라 전 연안에서 높은 빈도로 발견되며 인간 및 어패류에 감염을 유발시키는 박테리아의 일종이다. 본 연구는 서해안 양식장의 해수와 어패류에서 V. alginolyticus와 이에 대한 특이적인 용균성 파아지를 분리하였으며 분리된 파아지의 형태학적 특성을 전자현미경으로 확인 하였다. 또한 파아지의 핵산의 종류 및 구조 단백질의 특성 대한 연구가 수행되었다. 분리된 파아지는 형태학적으로 60 nm의 육각형 두부와 20 nm의 짧은 미부를 가진 podoviridae과로 분류되었다. 핵산을 분리한 결과 23 Kb 크기의 DNA로 판명 되었으며 구조 단백질은 37.8 kDa과 198 kDa 사이에 7종류의 단백질 분획이 존재함을 확인 하였다.

• Journal of Microbiology and Biotechnology
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• 제23권7호
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• pp.974-983
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• 2013

Bacillus amyloliquefaciens CB1 was isolated from cheonggukjang, a Korean fermented soy food. B. amyloliquefaciens CB1 secretes proteases with fibrinolytic activities. A gene homologous to aprE of Bacillus subtilis, aprECB1, was cloned from B. amyloliquefaciens CB1, and DNA sequencing showed that aprECB1 can encode a prepro-type serine protease consisting of 382 amino acids. When aprECB1 was introduced into B. subtilis WB600 using an E. coli-Bacillus shuttle vector, pHY300PLK, transformants showed fibrinolytic activity and produced a 28 kDa protein, the size expected for the mature enzyme. The 28 kDa fibrinolytic enzyme was purified from the culture supernatant of B. subtilis WB600 transformant. AprECB1 was completely inhibited by phenylmethylsulfonyl fluoride and almost completely inhibited by EDTA and EGTA, indicating that it is a serine metalloprotease. AprECB1 exhibited the highest specificity for N-succinyl-Ala-Ala-Pro-Phe-p-nitroanilide, a known substrate for ${\alpha}$-chymotrypsin. $A{\alpha}$ and $B{\beta}$ chains of fibrinogen were quickly degraded by AprECB1, but the ${\gamma}$-chain was resistant.

• Journal of Microbiology and Biotechnology
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• 제13권4호
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• pp.537-543
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• 2003

The mouse interferon gene (MuIFN-${\gamma}$) was cloned and then used to transform Saccharomyces cerevisiae. Expressed MuIFN-$\{gamma}$ protein (MuIFN-${\gamma}$) was successfully secreted into culture medium due to the presence oi the signal peptide of rice amylase 1A. Two different promoters fused to MuIFN-${\gamma}$ were tested: glyceraldehyde-3-phosphate dehydrogenase (GPD) promoter and a yeast hybrid ADH2-GPD (AG) promoter consisting of alcohol dehydrogenase II (ADH2) and GPD promoter. Using the hybrid promoter, the accumulation of MuIFN-${\gamma}$transcript was the highest after the 24 h cultivation, and then gradually decreased as the cultivation proceeded. However, both cell growth and recombinant MuIFN-${\gamma}$production reached their peaks after the 4-day cultivation. It was possible to produce 6.5 mg/l of MuIFN-${\gamma}$ without any changes in cell growth. Using GPD promoter, the MuIFN-${\gamma}$ transcript accumulation and the recombinant MuIFN-${\gamma}$ production followed the same pattern as the cell growth. However. compared to that of the hybrid promoter, the production of recombinant MuIFN-${\gamma}$ was 0.2 mg/l. The secreted MuIFN-${\gamma}$ had estimated molecular masses of 21 kDa and 23 kDa, which were larger than that of the encoded size due to glycosylation. The protection assay against the viral infection indicated that the recombinant MuIFN-${\gamma}$ was bioactive.

• Journal of Microbiology and Biotechnology
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• 제14권2호
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• pp.231-236
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• 2004

The inexpensive large-scale production of pure PGA (Penicillin G Acylase) has been a commercial goal. PGA has been used as a model enzyme in the development of simple one-step purification methods. In this study, the purification of poly-His tagged PGA protein secreted into the periplasmic space was carried out by using immobilized metal-ion affinity chromatography (IMAC). The PGA gene was obtained from E. coli ATCC 11105. Codons encoding histidines were fused at the C-terminus of the PGA gene by PCR. E. coli JM109 harboring pPGA-HIS6 vector produced active his-tagged acylases in the presence of lac promoter during cultivation at $26^{\circ}C$. The maximum specific activity of the acylase purified by using one-step chromatography after osmotic shock was 38.5 U/mg and was recovered with the yield of 70％. Both 23 kDa ($\alpha$) and 62 kDa ($\beta$) subunits were recovered by using IMAC with just C-terminus tagging of the $\beta$ subunit. The purification of the periplasmic fraction by osmotic shock and that of purified acylase was increased by 2.6-fold and 19-fold, respectively, compared to the crude extract.

• Journal of Ginseng Research
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• 제23권4호
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• pp.217-221
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• 1999

홍삼으로부터 염기성 수웅액 추출, 음이온교환 크로마토그래피 및 겔여과 크로마토그래피를 순차적으로 수행하여 항트롬빈 활성을 보이는 다당체를 분리하였다. 이 다당체는 셀룰로스 아세테이트막을 사용한 전기영동에서 하나의 띠로 나타나 비교적 순수하게 정제되었음을 알 수 있었고, 겔여과 크로마토그래피에서 결정된 평균 분자량은 약 177kDa이었다. $40.2\%$의 유론산, $9.2\%$의 황산기 및 $1.5\%$의 단백질을 포함하는 산성다당체였고, 구성 중성당으로 rhamnose, mannose, galactose, arabinose, glucose, fucose, xylose를 1.00 : 0.88 :0.86 : 0.78 : 0.70 : 0.33 : 0.22의 비율로 포함하고 있었다. 이 다당체는 트롬빈에 의한 피브리노겐의 응고를 농도에 비례하여 저해하였고, 혈장을 사용한 실험에서 내인성 경로를 통해 혈액응고를 저해하는 것으로 나타났다.

• 한국축산식품학회지
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• 제34권6호
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• pp.822-828
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• 2014

In this study, the existence of skeletal muscle troponin I (smTnI), well-known as a muscle protein in fat tissues, and the utilization of smTnI as a biomarker for the identification of fat adulteration were investigated. A commercial antibody (ab97427) specific to all of animals smTnI was used in this study. Fat and meat samples (cooked and non-cooked) of pork and beef, and chicken considered as representative meats were well minced and extracted by heating and non-heating methods, and the extracts from fat and meat tissues were probed by the antibody used in both enzyme-linked immunosorbent assay (ELISA) and immunoblot. The antibody exhibited a strong reaction to all meat and fat extracts in ELISA test. On the other hand, the results of immunoblot analsis revealed a 23 kDa high intensity band corresponding to the molecular weight of smTnI (23786 Da). These results demonstrate that the existence of smTnI in all animal fat tissues. Since there are monoclonal antibodies specific to each species smTnI, smTnI in fat tissues could be used as a biomarker to identify or determine animal species adulterated in meat products. Therefore, an analytical method to identify fraudulent fat adulteration can be developed with an antibody specific to each species smTnI.

• 생명과학회지
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• 제30권11호
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• pp.931-938
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• 2020

TCTP는 다양한 진핵생물에서 풍부하게 존재하는 단백질 중에 하나이며, 암, 세포 증식, 유전자 조절 등과 관련된 세포의 생리학적 기작에서 중요한 역할을 담당하는 것으로 알려져 왔다. 더구나, TCTP는 dithiothreitol (DTT)나 hydrogen peroxide (H₂O₂)에 의해 유도되는 산화적 스트레스에 대한 저항성에 관여하는 중요한 단백질로 주목 받아 왔다. 한편, 극지역 서식 생물들은 강한 자외선에 의해 발생한 활성산소를 조절하기 위한 다양한 항산화 방어체계를 가지고 있다. 본 연구에서는 북극 동물플랑크톤 Calanus glacialis에서 분리된 TCTP가 산화적 스트레스 하에서 E. coli 세포의 저항성에 미치는 효과를 관찰하였다. C. glacialis에서 분리된 TCTP 유전자(ORF 522 bp) 서열을 분석하였고, 약 23 kDa의 재조합 단백질을 제작하였다. 관찰 결과, TCTP 재조합 단백질이 E. coli 세포에서 과발현 되었을 때, 세포들은 H₂O₂에 의해 유도된 산화적 스트레스에 대한 저항성이 증가하는 것을 확인하였다. 본 관찰을 통해, 북극 C. glacialis TCTP 단백질의 항산화 조절자로서의 역할에 대한 가능성을 처음으로 제시하였다.

• 한국물환경학회지
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• 제23권6호
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• pp.843-849
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• 2007

Monitoring of NOM characteristics is important for improving removal efficiency of natural organic matter (NOM) in water treatment processes. In this study, several NOM characteristics, which include specific UV absorbance (SUVA), total carbonate content, molecular weight distribution, and fluorescence properties, were measured using samples collected from a pilot-scale water treatment plant consisting of coagulation/flocculation (C/F), filtration, ozonation and granular activated carbon (GAC) processes. The highest removal of NOM was observed in C/F and filtration processes as demonstrated by the reduction of dissolved organic carbon (DOC) by 25% and 21%, respectively. Despite nearly no change in DOC, however, the lowest SUVA value and the highest total carbohydrate content were observed in the sample from ozonation process. This indicates that non-degradable aromatic compounds become depleted and biodegradable organic compounds are enriched during the process. Comparison of synchronous fluorescence spectra of the samples showed that ozoation process increased protein-like fluorescence while it decreased fulvic-like and terrestrial humic-like fluorescence. Consistently, a slight peak of protein-like fluorescence was observed in the sample from ozonation process. The greatest change in molecular weight distributions of the samples was observed in C/F process. Comparison of size exclusion chromatogram of the samples revealed that NOM fractions with the molecular weight greater than 2000 Da were reduced by over 90% after C/F process. SUVA values and total carbohydrate content of the samples were well correlated with a ratio of protein-like fluorescence and terrestrial humic-like fluorescence intensities with the correlation coefficients of 0.99 and 0.91, respectively. This suggests that synchronous fluorescence properties of NOM could be used as useful tolls for monitoring changes of some NOM characteristics during water treatment processes.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVI)
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• pp.35-35
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• 2005

Recombinant human $interferon-{\beta}-1a(rIFN-{\beta})$ is a single glycosylated protein (at N80, 1N) with anti-viral activity. However, present drugs have a relatively short serum half-life of $rIFN-{\beta}$, thus patients suffer from frequent $infections.^{1)}$ To improve its half-life, eight glycosylation analogs were prepared, which have additional N-linked glycosylation consensus sequences (N-X-T/S) within the $IFN-{\beta}$ molecule and/or at C-terminal. Each $rIFN-{\beta}$ analog was examined for the presence of additional N-linked glycosylation and the maintenance of anti-viral activity in CHO cells. The molecular weights of five analogs were not changed. However, two analogs, R27T within $rIFN-{\beta}$ (27 kDa, 2N) and GNITVNITV at C-terminal (29kDa, 2N), showed a clear increase in molecular weights, compared to native $rIFN-{\beta}$ (23 kDa, 1N). And another combined analog of R27T+GNITVNITV showed increased molecular weight (33 kDa, 3N). It was confimed that the molecular weight increment of analogs was caued by the N-linked glycosylation with the treatment of N-glycansae. In the case of anti-viral activity, the analog GNITVNITV showed a reduction in activity compared to native $IFN-{\beta}$, whereas the analogs R27T and R27T+GNITVNITV were found to have distinctly increased activities. Pharmacokinetic study in rats also disclosed that the analogs R27T and R27T+GNITVNITV had 2 3 fold increased serum half-life, respectively. In conclusion, the addition of N-linked glycosylation in $rIFN-{\beta}$ increased serum half-life, thereby its less frequent administration will be expected.