• Biotechnology and Bioprocess Engineering:BBE
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• 제3권2호
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• pp.67-70
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• 1998

In order to understand the influence of ferroxidase center on the protein assembly and solubility of tadpole ferrin, three mutant plasmids, pTH58K, pTH61G, and pTHKG were constructed with the aid of site-directed mutagenesis and mutant proteins were produced in Eshcerichia coli. Mutant ferritin H-subunits produced by the cells carrying plasmids pTH58K and pTHKG were active soluble proteins, whereas the mutant obtained from the plasmid pTH61G was soluble only under osmotic stress in the presence obtained from the plasmid pTH61G was soluble only under osmotic stress in the presence of sorbitol and betaine. Especially, the cells carrying pTH61G together with the plasmid pGroESL harboring the molecular chaperone genes produced soluble ferritin. The mutant ferritin H-subunits were all assembled into ferritin-like holoproteins. These mutant ferritns were capable of forming stable iron cores, which means the mutants are able to accumulate iron with such modified ferroxidase sites. Further functional analysis was also made on the individual amino acid residues of ferroxidase center.

• Preventive Nutrition and Food Science
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• 제12권2호
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• pp.103-110
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• 2007

The protein profiles among Korean rice cultivars were assessed by total protein determination, solubility fractionation, SDS-PAGE analysis and scanning densitometry. In the extraction of protein, the SDS/urea system at a neutral pH was more efficient than that at alkaline pH. The determination of total protein showed that the protein content was similar among cultivars, ranging from 87.9 to 92.7 mg/g dry weight. Additionally, the water/NaCl-soluble protein fraction, containing 14${\sim}$16 kDa albumin and 22 kDa globulin ${\alpha}$-globulin, was also similar among cultivars, with a range of 9.94 to 11.98 mg/g dry weight. The SDS-PAGE/densitometry of total protein showed that there was no discernable difference in proteins of higher molecular weights among various cultivars, whereas the amount of lower molecular weight proteins (14${\sim}$16 kDa) is somewhat variable among cultivars. Furthermore, SDS-PAGE analysis of water/NaCl-soluble and propanol-soluble fractions indicates that there is a discernible change in the content of albumin, globulin or prolamin among cultivars. Thus, the PAGE/densitometry method, preceded by solubility fractionation, is useful for examining differences in protein profiles of rice cultivars.

• 한국축산식품학회지
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• 제31권6호
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• pp.817-826
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• 2011

The technological effects of Makgeolli lees fiber (0, 0.5, 1.0, 2.0, and 4.0%) on chicken salt-soluble breast meat proteins in a model system on proximate composition, physicochemical properties, and textural properties were investigated. Makgeolli lees fiber was obtained from Makgeolli brew processing, and the by-products showed good dietary fiber. The moisture and ash contents, water holding capacity, redness, yellowness, hardness, and apparent viscosity of chicken salt-soluble meat protein heat-induced gel systems with Makgeolli lees fiber were all higher than the control without Makgeolli lees fiber. However, protein solubility and electrophoretic patterns did not differ among the control and treatments with Makgeolli lees fiber samples. The chicken salt-soluble protein heat-induced gel systems incorporating Makgeolli lees fiber had improved water holding capacity, textural properties, and viscosity due to Makgeolli lees fiber addition. These results suggest that the addition of 4.0% Makgeolli lees fiber to gel is helpful to improve the physical properties of heat-induced gels.

• BMB Reports
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• 제36권2호
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• pp.154-158
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• 2003

Collagen is a family of proteins which consists of several genetically distinct molecular species and is intimately involved in tissue organization, function, differentiation and development. The purpose of this study was to investigate the concentration of different hydroxyproline (Hyp) fractions viz., total, free, peptide-bound, protein-bound, soluble- and insoluble-collagen hydroxyproline (Hyp) in various bovine tissues. Results showed that liver had the highest concentration of free Hyp followed by kidney, brain, spleen, lungs, muscle and heart. Liver also had the highest concentration of peptide-bound collagen Hyp followed by kidney, heart, spleen, lungs, brain and muscle. The concentration of protein-bound collagen Hyp was highest in the liver, followed by kidney, spleen, lungs, muscle, brain and heart. Total Hyp was highest in the liver, followed by kidney, spleen, brain, heart, muscle and lungs. Liver also had significantly high concentration of collagen as compared to other tissues examined (P<0.001). Spleen had the significantly higher concentration of soluble-collagen Hyp when compared to other tissues (P<0.001). This was followed by heart, muscle, lungs, brain, kidney and liver. Heart had the highest concentration of insoluble-collagen Hyp followed by lungs, kidney, liver, muscle, spleen and brain. The variation among the insoluble-collagen Hyp concentration of heart and muscle, spleen and brain was significant (P<0.001). We speculate that these differences could be due to the variation in turn over of rate of collagen metabolism in this species.

• 한국식품영양과학회지
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• 제28권2호
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• pp.403-408
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• 1999

This study was conducted to investigate chemical properties, quality stability and utilization of approved sardine surimi(ASS) which is developed our laboratory. The product yield of the ASS was about 3 times higher than that of usual sardine surimi(SS). The proper addition concentration of sodium bicarbonate was 0.1% for the neutralization of the ASS. The content of salt soluble protein nitrogen in the ASS was about the half of that in the SS, while the content of water soluble protein nitrogen was 2.4 times higher in ASS. The total amount of free amino acids in the ASS was about 11 times higher than that of the SS. Predominant free amino acids in the ASS were histidine, taurine, glutamic acid and alanine, and those four amino acids occupied 94% of total amount of free amino acids. During cold storage at 21oC for 6 months, the quality of ASS was more stable than that of SS in judging from changes of water soluble and salt soluble protein nitrogen, AV and POV. Quality of fish burger, fish sausage and fried fish paste processed in accordance with commercial processing preparation using the ASS or SS exclusively and mixtures which other white meat fish surimi(alaska pollack, hair tail and sole) were proportionallly added to each of two types of sardine meat were evaluated. In case of fish burger, the product processed from the ASS only were superior.

• 한국식품과학회지
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• 제10권1호
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• pp.83-87
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• 1978

한국산 호박씨중에서 지방(脂肪)을 추출하여 지방산(脂肪酸)의 종류를 조사하였고 또한 물에 가용(可溶)인 단백질(蛋白質) 및 불용성(不溶性) 단백질(蛋白質)을 분리(分離)하여 Disc 전기영동으로 단백질의 Pattern을 확인하고 아미노산 조성(組成)을 관찰하였다. 1. 호박씨의 일반성분중 지방은 46.5% 단백질 25.5%를 함유하고 있다. 2. 호박씨기름의 지방산(脂肪酸) 조성(組成)은 linoleic acid 51.74%, oleic acid 22.2%, palmitic acid 18.1%, stearic acid 7.84%로 이들 4가지를 주 지방산으로 하고 있다. 3. 호박씨 단백질(蛋白質)의 아미노산(酸) 조성(組成)은 tyrosine, glutamic acid, aspartic acid, leucine, glycine등을 다량(多量) 함유하고 있으나 함황(含黃) 아미노산(酸)은 함유(含有)하고 있지 않다. 4. 단백질의 Disc전기영동 결과 가용성(可溶性) 단백질(蛋白質)에서 13개의 band와 불용성(不溶性) 단백질에서 4개의 band가 분리 되었다.

• Journal of Microbiology and Biotechnology
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• 제17권11호
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• pp.1898-1903
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• 2007

We attempted to modulate the overall protein expression rate through the addition of a repressor against the araBAD promoter system of Escherichia coli, in which glucose was used as a repressor. Therefore, 0.5% L-arabinose was initially contained as an inducer in culture medium, and either 2% glucose or 2% glycerol was used as a carbon source, and it was found that the expression of recombinant interferon-${\alpha}$ could be observed at the beginning of the batch culture when glycerol was used as a carbon source. However, when glucose was used, the initiation of recombinant interferon-${\alpha}$ expression was delayed compared with that when glycerol was used. Furthermore, when the addition of 0.5% glucose was carried out once or twice after 0.5% L-arabinose induction during DO-stat fed-batch culture, the distributions of soluble and insoluble recombinant interferon-${\alpha}$ were modulated. When glucose was not added after the induction of L-arabinose, all of the expressed recombinant interferon-${\alpha}$ formed an inclusion body during the later half of culturing. However, when glucose was added after induction, the expressed recombinant interferon-${\alpha}$ did not all form an inclusion body, and about half of the total recombinant interferon-${\alpha}$ was expressed in a soluble form. It was deduced that the addition of glucose after the induction of L-arabinose might lower the cAMP level, and thus, CAP (catabolite activator protein) might not be activated. The transcription rate of recombinant interferon-${\alpha}$ in the araBAD promoter system might be delayed by the partial repression. This inhibition of the transcription rate probably resulted in more soluble interferon-${\alpha}$ expression caused by the reduction of the protein synthesis rate.

• Journal of Microbiology and Biotechnology
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• 제17권11호
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• pp.1868-1874
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• 2007

We have developed a robotic system for an automated parallel cell cultivation process that enables screening of induction parameters for the soluble expression of recombinant protein. The system is designed for parallelized and simultaneous cultivation of up to 24 different types of cells or a single type of cell at 24 different conditions. Twenty-four culture vessels of about 200 ml are arranged in four columns${\times}$six rows. The system is equipped with four independent thermostated waterbaths, each of which accommodates six culture vessels. A two-channel liquid handler is attached in order to distribute medium from the reservoir to the culture vessels, to transfer seed or other reagents, and to take an aliquot from the growing cells. Cells in each vessel are agitated and aerated by sparging filtered air. We tested the system by growing Escherichia coli BL21(DE3) cells harboring a plasmid for a model protein, and used it in optimizing protein expression conditions by varying the induction temperature and the inducer concentration. The results revealed the usefulness of our custom-made cell cultivation robot in screening optimal conditions for the expression of soluble proteins.

• Korean Chemical Engineering Research
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• 제47권4호
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• pp.501-505
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• 2009

본 논문에서는 혈관내피세포에서 활성화된 단백질 C(Activated Protein C, APC)의 항염증 작용에서 수용성 EPCR(Soluble Endothelial Protein C Receptor, sEPCR)의 효과를 관찰하였다. sEPCR은 APC가 매개하는 항염증 작용에 있어 내피세포막의 보호효과를 저해하고, 혈관내피세포에 대한 백혈구의 부착저해 효과를 억제하며, 혈관내피세포를 관통하는 백혈구의 이동을 저해하는 효과를 억제한다. 그리고 흥미롭게도 sEPCR은 내피세포에서 TNF-alpha에 의한 세포부착단백질의 발현을 억제하는 APC의 기전을 저해함으로써 APC가 가지는 항염증 효과를 억제한다. 이것은 APC의 Gla 도메인이 내피세포의 수용체인 EPCR에 결합할 수 있는 부위에 sEPCR이 상호작용함으로써 더 이상 APC이 세포막에 존재하는 EPCR과 결합을 못함으로써 APC의 항염증 작용은 억제되는 것을 의미한다. 이 결과는 향후 중증 패혈증 및 염증질환을 효과적으로 치료할 수 있는 신약개발에 중요한 단서를 제공할 것이고 내피세포에서 아직 명확하게 밝혀지지 않은 APC의 항염증 작용의 기전을 밝히는 데 좋은 정보를 제공할 것이다.

• 한국미생물·생명공학회지
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• 제16권2호
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• pp.105-110
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• 1988

전분이용성 세포융합 효모를 이용하여 단세포단백질 생산을 위한 기초실험을 행하였다. 전분배지에서 균체생성이 우수한 fusant12 균주의 배양조건은 최적질소원 (NH$_4$)$_2$SO$_4$ 0.1%, 최적 soluble starch 농도 7%, 최적 초기pH5.6이었다. Fusant12균체의 자기소화에 의한 가용성 단백질의 추출은 효모현탁액에 ethyl acetate를 5%(v/ v)되게 첨가하여 30min간 액화전처리과정을 행하므로 효과적으로 얻을 수 있었다. 전분이용성 효모인 fusant 12균주와 비전분이용성 효모인 Torulopsis candida의 혼합배양으로 균체생성량을 증가시킬 수 있었으며, 혼합배양시 종균접종혼합비는 6대4일 때 효과적이었다. Fusant 12균주 단독 및 Torulopsis candida와의 혼합배양시 tapioca 배지에서의 균체생성량은 soluble starch 배지에서 보다 약 2.5배 증가하였다. 건조균체의 조단백질함량은 39%, 핵산함량은 5.8%이고 균체단백질은 FAO 표준단백질과 비교하여 필수아미노산중 methionine 함량이 낮으며, Iysine 함량은 높았다.