• Journal of Microbiology and Biotechnology
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• 제11권1호
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• pp.40-49
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• 2001

The present work presents a novel approach for the dynamic quantification of respiration rates on a small scale by using lysine-producing Corynebacterium glutamicum ATCC 21253. Cells sampeld from batch cultures at different times were incubated ina 12-ml scale bioreactor equipped with a membrane mass spectrometer. Under dynamic conditions, gas exchange across the gas-liquid phase, specific respiration rates, and RQ values were precisely measured. For this purpose, suitable mass balances were formulated. The transport coefficients for $O_2$ and $CO_2$, crucial for calculating the respiration activity, were determined as $k_La_{O2}=9.18h^{-1}$ and $k_La_{CO2}=5.10h^{-1}$ at 400 rpm. The application of the proposed method to batch cultures of C. glutamicum ATCC 21253 revealed the maximum specific respiration rates of $q_{O2}=8.4\;mmol\;g^{-1}h^{-1}\;and\;q_{CO2}=8.7\;mmol\;g^{-1}h^{-1}$ in the middle of the exponential growth phase after 5 h of cultivation. When the cells changed from growth to lysine production due to the depletion of the essential amino acids theonine, methionine, and leucine, $q_{O2}\;and\;q_{CO2}$ decreased significantly and RQ increased. The respiration data exhibited an excellent agreement with previous cultivations of the strain [13]. This confirms the potential of the developed approach to realistically reflect the metabolic activities of cells at their point of sampling. The short-term influence of added threonine, methionine, and leucine was highest during the shift from growth to lysine production, where $q_{O2}\;and\;q_{CO2}$ increased 50% within one minute after the pulse addition of these compounds. Non-growing, yet lysine-producing cells taken from the end of the batch cultivation revealed no metabolic stimulation with the addition of threonine, methionine, and leucine.

• 생명과학회지
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• 제10권3호
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• pp.273-278
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• 2000

식용식물 이면서 한방재료로 이용되고 있는 부추의 이용 효율을 증대시킬 목적으로 부추씨의 이화 학적 특성과 수용성 추출물의 항산화 활성을 측정하였다. 부추씨의 일반적 조성을 보면 조단백질 25.7%, 조지방 16.6%, 조회분 2.9%, 수분 4.4%로 나타났다. 아미노산 조성은 건물 중량 100g 당 proline 11.0 g 으로 가장 높았으며, glutamic acid 4.91 g, arginine 2.12 g, aspartic acid 1.62 g, leucine 1.31 g, valine 1.16 g, methionine 1.15 g 순으로 나타났다. 부추씨의 무기질 성분은 칼륨 215 ppm, 칼슘 142 ppm, 철 124 ppm, 마그네슘 100 ppm 순으로 나타나 칼슘과 철분을 많이 함유하였다. 주요 지방산으로 linoleic acid (C18:2) 71.9%, oleic acid(C18:1) 12.7%, palmitic acid(C16:0) 8.6% 및 stearic acid(C18:0) 1.4% 순 으로 전체의 약 93%를 차지하였다. 부추씨로부터 열침 온도에 따른 총폴리페놀 화합물의 함량 변동은 2$0^{\circ}C$ 추출물에 비해 4$0^{\circ}C$ 추출물에서 27%, 6$0^{\circ}C$ 추출물에서 51% 증가하였다. 부추씨 수용성 추출물을 DPPH 환원법으로 항산화 활성을 측정한 결과, 부추씨는 BHT 보다 활성이 나타났다. 이상과 같이 부추 씨는 아미노산, 무기질 및 지방산을 풍부하게 함유하고 있어 영양적인 면에서도 상당한 가치를 가지는 식품재료로 이용될 가능이 있는 것으로 사료된다.

• Applied Biological Chemistry
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• 제25권2호
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• pp.75-82
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• 1982

콩나물 제조중 식물성장 조절제 혼합액(IAA와 BA)을 2회 처리하여 그의 성분 및 생육상태의 변화를 비교실험하였다. 콩나물의 성장중 생육상태의 변화는 식물성장 조절제 처리구에서 35%의 신장이 억제되었으며 생체중량, 건조물량 및 배축부의 두께는 각각 $10{\sim}20%$, 5%, 40%의 촉진효과를 나타내었고 취약성 및 경도는 약간의 증가를 나타내었다. 또한 처리구에서는 잔뿌리의 발생이 억제되어 잔뿌리 없는 콩나물을 제조할 수 있었다. 콩나물 성장중 조단백질과 조지방의 변화는 처리구에서 대조구보다 각각 $5{\sim}10%$, 10%의 증가효과를 나타내었으며 vitamin C의 변화는 처리구에서 대조구보다 70%의 생성촉진효과를 나타내었다. 식물생장 조절제 처리구의 아미노산 조성은 lysine 17.22mg, arginine 18.45mg, 그리고 methionine이 3.56mg으로 각기 대조구에 비하여 16%, 108%, 15%의 증가 효과를 나타내었으며 proline은 5.03mg으로 대조구에 비하여 106%로 감소되었다. 지방산조성은 처리구, 대조구 모두 비슷한 조성을 나타내었으며 처리구의 지방산조성은 linoleic 57.14%, oleic 18.6%, palmitic 11.17%, linolenic 9.22%의 순이며 P/S ratio는 4.40으로 대조구의 4.37 보다 약간 높았다.

• Archives of Pharmacal Research
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• 제20권5호
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• pp.459-464
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• 1997

The human liver cDNA clone UDPGTh2, encoding a liver UDP-glucuronosyltransferase (UDPGT) was isolated from a .gamma. gt 11 cDNA library by hybridization to mouse transferase cDNA clone, UDPGTm1. UDPGTh2 encoded a 529 amino acid protein with an amino terminus membrane-insertion signal peptide and a carboxyl terminus membrane-spanning region. There were three potential asparagine-linked glycosylation sites at residues 67, 68, and 315. In order to obtain UDPGTh2 protein encoded from cloned human liver UDP-glucuronosyltransferase cDNA, the clone was inserted into the pSVL vector (pUDPGTh2) and expressed in COS 1 cells. The presence of a transferase with Mr-52,000 in transfected cells cultured in the presence of $[^{35}S]$ methionine was shown by immunocomplexed products with goat antimouse transferase IgG and protein A-Sepharose and analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. The expressed UDPGT was a glycoprotein as indicated by electrophoretic mobility shift in Mr-3,000-4,000 when expressed in the presence of tunicamycin. The extent of glycosylation was difficult to assess, although one could assume that glycosyl structures incorporated at the level of endoplasmic reticulum were always the core oligosaccharides. Thus, it is likely that at least two moieties inserted can account for the shift of Mr-3,000-4,000. This study demonstrates the cDNA and deduced amino acid sequence of human liver UDP-glucuronosyltransferase cDNA, UDPGTh2.

• 대한핵의학회지
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• 제38권2호
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• pp.198-204
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• 2004

Tumor cell proliferation is considered to be a useful prognostic indicator of tumor aggressiveness and tumor response to therapy but in vitro measurement of individual proliferation is complex and tedious work. PET imaging provides a noninvasive approach to measure tumor growth rate in situ. Early approaches have used $^{18}F$-FDG or methionine to monitor proliferation status. These 2 tracers detect changes in glucose and amino acid metabolism, respectively, and therefore provide only an indirect measure of proliferation status. More recent studies have focused on DNA synthesis itself as a marker of cell proliferation. Cell lines and tissues with a high proliferation rate require high rates of DNA synthesis. $[^{11}C]Thymidine$ was the first radiotracer for noninvasive imaging of tumor proliferation. The short half-life of $^{11}C$ and rapid metabolism of $[^{11}C]Thymidine$ in vivo make the radiotracer less suitable for routing use. Halogenated thymidine analogs such as 5-iodo-2-deoxyuridine (IUdR) can be successfully used as cell proliferation markers for in vitro studies because these compounds are rapidly incorporated into newly synthesized DNA. IUdR has been evaluated as a potential in vivo tracer in nuclear medicing but the image qualify and the calculation of proliferation rates are impaired by its rapid in vivo degradation. Hence, the thymidine analog $3'-deoxy-3'-^{18}F-fluorothymidine$ (FLT) was recently introduced as a stable proliferation marker with a suitable nuclide half-life and stable in vivo. $[^{18}F]FLT$ is phosphorylated to 3-fluorothymidine monophosphate by thymidine kinase 1 and reflects thymidine kinase 1 activity in proliferating cell. $[^{18}F]FLT$ PET is feasible in clincal use and well correlates with cellular proliferation. Choline is a precursor for the biosynthesis of phospholipids (in particular, phosphatidylcholine), which is the essential component of all eukaryotic cell membranes and $[^{11}C]choline$, which is a new marker for cellular proliferation.

• 한국수산과학회지
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• 제12권3호
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• pp.191-200
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• 1979

새로운 단백질자원인 남빙양산크릴의 효율적인 이용을 위한 기초자료를 얻기 위하여 식품원료학적인 특성의 구명에 주목적을 두어 연구를 수행하였다. 즉 1978년 1월 30일 남비양에서 어획하여 생동결 및 자숙동결한 크릴을 시료로 하여 일반성분조성, 아미노산조성, 중금속류의 함량, 가식부의 비율, 해동시의 drip 발생량 및 그 결성 등에 대하여 연구검토하였으며, 그 결과를 요약하면 다음과 같다. 1. 1. 일반성분조성에 있어서 생동결크릴은 자숙동결크릴에 비하여 지방 및 유리아미노실소의 함량이 높고 회분함량이 낮았다. VBN량은 생동결크릴이 $37.6mg\%$, 자숙동결크릴이 $26.4mg\%$로 상당히 높고, pH는 생동결크릴은 7.1, 자숙동결크릴이 7.2로 비교적 낮았는데, 이러한 VBN 및 pH값은 시료 크릴의 저장기간이 길고, 냉동보관의 빈번한 변동으로 선도가 많이 저하한 때문이라고 생각된다. 생동결크릴의 육질부아미노산조성은 glutamic acid, aspartic acid, lysine, proline 및 leucine의 함량이 높고, methionine, histidine, serine, tyrosine 및 phenylalanine의 함량이 적었으며, 필수아미노산에 있어서는 lysine 및 leucine의 함량이 높고 methionine 및 phenylalanine의 함량이 낮았다. 한편 유리아미노산조성에 있어서는 proline, lysine, glycine, arginine 및 alanine의 함량이 높고 histidine, methionine, aspartic acid, serine 및 threonine의 함량이 낮았으며, 필수아미노산에 있어서는 lysine 및 leucine의 함량이 많고 methionine 및 threonine의 함량이 낮았다. 크릴의 구성아미노산이나 유리마미노산 조성에 있어서 필수아미노산인 lysine의 함량이 많은 점은 영양적으로 의의가 크다고 할 수 있다. 3. 크릴의 중금속함량은 Hg가 $0.039\~0.048ppm$, Pb가 $0.06\~0.11ppm$, Zn가 0.32이하 Cd가 $0.008\~0.012ppm$, C가 ND, Fe가 $0.61\~0.68ppm$, Cu가 $0.87\~1.37ppm$로 전반적으로 함량이 낮았다. 단 Cu의 함량이 비교적 높은 것은 갑각류의 혈액구성성분인 때문이라고 생각된다. 4. 가식부와 부하식부의 비율은 생동결크릴이 37:63이고 자숙동결크릴이 42:58로 외견상 가식부비율이 자숙동결크릴이 많았다. 5. 해동시의 drip의 유출량은 생동결크릴이 약 $36\%$ 자숙동결이 약 $24\%$로 생동결크릴이 많았고, 크릴의 성분조성에 있어서는 생동결크릴의 경우가 고형조단백질 및 조지방의 함량이 현저하게 많았고 회분함량은 적었다.

• Journal of Animal Science and Technology
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• 제45권2호
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• pp.319-326
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• 2003

본 실험은 쇠고기의 비 선호부위를 고도로 이용하기 위한 연구의 일환으로 쇠고기의 염통과 지라를 각종효소로 가수분해하여 얻은 분획물을 한외여과와 gel-filtration, 그리고 HPLC를 이용하여 분리 및 정제하여 얻은 펩타이드의 ACE 저해 활성을 검토한 실험이다. 쇠고기 염통과 지라에서 수용성 단백질을 추출한 다음 효소 처리하여 4, 8, 12, 24시간 동안 37$^{\circ}C$에서 배양하였다. 염통과 지라단백질의 가수분해물의 ACE 저해 활성을 측정한 결과 염통에서는 Thermolysin과 Proteinase A 효소를 12시간 혼합처리한 가수분해물에서 가장 좋은 ACE 저해 효과를 보여주었고 지라에서는 Thermolysin과 Protease 효소를 24시간 혼합처리한 가수분해물에서 ACE 저해 효과가 가장좋았다. ACE 저해효소가 가장 좋은 가수분해물을 Ultrafiltration 통해 분리하였으며, 분리 정제된 가수분해물을 Gel-filtration을 통해서 분획 하였다. 이때 염통에서는 F11, F36, F51, F63, F72의 큰 분획물을 얻었고 지라에서는 F30, F55, F71, F91에서 큰 분획물을 얻었다. 이 분획물들의 ACE 저해 활성을 측정한 결과 염통에서는 F72에서 $IC_{50}$값 0.37mg/ml로 ACE 저해 활성이 가장 좋았다. 지라에서는 F30에서 $IC_{50}$값 1.840 mg/ml로 ACE 저해 활성이 가장 좋았다. 그리고 여기서 활성이 좋은 염통을 가지고 Reversed- Phase HPLC를 이용하여 분리 한 결과 4개의 큰 피크들을 얻을 수 있었다. 그 결과 peak 1, peak 2, peak 3, peak 4의 IC50값은 각각 0.28mg/ml, 0.26mg/ml, 0.25mg/ml, 0.35mg/ml이었다. 이 peak들의 아미노산을 분석한 결과, peak 1에서는 glycine과 methionine, peak 2는 proline, cystine, methionine, peak 3는 proline, peak 4는 alanine, methionine, leucine 이 주요 구성 성분 아미노산이었다. 위 실험 결과로서, 염통과 지라에서의 ACE저해 활성은 염통이 지라보다 좋았고, 특히 Thermolysin과 Proteinase A 효소를 12시간 배양한 염통단백질 가수분해물에서 가장 좋은 ACE 저해 활성 peptide을 얻을 수 있었다.

• 한국가금학회지
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• 제22권3호
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• pp.155-160
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• 1995

To evaluate the nutritive values of outdoor mass cultivated Spirulina platensis both chemical analysis and bioassay were carried out using adult cockerels. Blue-green algae, Spirulina platensis contained about 71g /l00g DM of crude protein with balanced amino acid profiles although methionine is liable to he limiting to animals. Compared to fish meal, calcium content and calcium : phosphorus ratio of the Spirulina were not suitable in terms of animal requirements. Reasonable amount of y-linolenic acid(C18: 3 $\omega$6) in Spirulina platensis draws a clinical attention due to its historically recognized pharmacotheraputic functions. Metabolizable energy contents of Spirulina were 3.67 and 3.11 mcal /kg DM for TMEn and AMFn, respectively, which therefore, can he a reliable energy source for poultry. True amino acid availabilities of essential amino acids of Spirulina platensis were higher than 90% for poultry, which is better than comparative ingredient like fish meal. Overall data from both chemical analysis and bioassay demonstrated that the Spirulina platensis could he a favorable protein feedstuffs for poultry.

• Journal of Microbiology and Biotechnology
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• 제11권2호
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• pp.281-286
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• 2001

Since the number of amino groups which are exposed by deacetylation of acetyl-D-glucosamine influences antimicrobial activity, a chitosan oligosaccharide (COS) derivative by N-conjugation of COS with asparagine, an amino acid with two amino groups, was synthesized and the antimicrobial effect on E. coli growth was compared with other COS derivatives which were N-conjugated with glycine, alanine, aspartic acid, cysteins, an methionine, and unmodified COS. The structure of asparagine N-conjugated COS (Asn-COS) derivative was identified by using a FT-IR, $^{13}C\;FT-NMR$, and an elemental analyzer. The antimicrobial activity of Asn-COS against E. coli growth was significantly improved as compared to the other COS derivatives as well as COS itself. This means that Asn-COS with two positive charges strongly interacts with the carboxyl negative charges on the bacteria cell wall. The results for Asn-COS were as follows: 100% bactericidal activity, 0.002% MIC, and no growth of E. coli during 3 days of culture time, suggesting that Asn-COS may be useful as a new antibiotic agent.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 2000년도 Proceedings of 2000 KSAM International Symposium and Spring Meeting
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• pp.208-213
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• 2000

Penicillium fellutanum produces a phosphorylated, choline-containing extracellular peptido-polysaccharide, peptidophosphogalactomannan (pPxGM) (8). The $\^$13/C-methyl labeled pPxGM ([methyl-$\^$13/C]pPxGM) was prepared from the cultures supplemented with L-[methyl-$\^$13/C]methionine or [2-$\^$13/C]glycine and was used as a probe to monitor the fate of phosphocholine in this polymer. Addition of purified [methyl-$\^$l3/C]pPxGM to growing cultures in low phosphate medium resulted in the disappearance of [methyl-$\^$13/C]phosphocholine and -N,N'-dimethyl-phosphoethanolamine from the added [methyl-$\^$13/C]pPxGM. Two $\^$l3/C-methyl-enriched cytoplasmic solutes, choline-O-sulfate and glycine betaine, were found in mycelial extracts, suggesting that phosphocholine-containing extracellular pPxGM of P.fellutanum is a precursor of intracellular choline-O-sulfate and glycine betaine and thus of phosphatydilcholine (l0). $\^$13/C-Methyl-labeled cells grown in 3 M NaCl-containing medium showed 2.6- and 22-fold more accumulation of $\^$13/C-methyl labeled choline-O-sulfate and glycine betaine, respectively, originated from the extracellular [$\^$13/C-methyl]pPxGM than those grown without added NaCl. The results suggest that, in addition to glycerol and erythritol, glycine betaine and choline-O-sulfate and thus choline are also osmoprotectants and hence that pPxGM is involved in osmotolerance of this fungus (11). Taken collectively, the $\^$l3/C- and $\^$31/P-NMR analyses of cytosolic solute pools and structural modulation of extracellular pPxGM corresponding to environmental stimuli in P. fellutanum, provided evidence that pPxGM is involved in cellular choline metabolism, osmotolerance, and recycling of metabolites.