• 한국미생물·생명공학회지
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• 제37권2호
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• pp.153-159
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• 2009

Rhodobacter capsulatus 유래의 hemA 유전자를 항시발현 벡터(pHCEIIB vector)에 클로닝한 후 과발현시킨 Escherichia coli BLR(DE3) 균주를 사용하여, 5-aminolevulinic acid (ALA) 생산을 위한 적정 배양조건을 조사하였다. ALA 생산을 위한 배양온도는 $37^{\circ}C$보다는 $30^{\circ}C$에서 더 나은 결과를 나타내었다. Glycine 농도가 세포생장에 미치는 영향이 컸으며, 세포생장을 저해하지 않고ALA를 고농도로 생산하기 위한 적정 glycine 농도는 5-10 g/L 수준이었다. Succinic acid의 적정 첨가수준은 10-20 g/L이었으며, succinic acid의 일부를 glutamate로 대체할 경우에 ALA의 생산량을 향상시키는 효과가 있었다. 한편, 배지 중의 glucose 첨가는 ALA 생산성을 저하시키는 결과를 초래하였다. 이상과 같은 배양 조건 최적화를 통한 jar-fermentor 발효실험을 통하여, 고가의 유도제(IPTG)나 ALA dehydratase inhibitor를 첨가하지 않고도 8.2 g/L 수준의 고농도 ALA를 얻을 수 있었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 센서 박막재료 반도체재료 기술교육
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• pp.47-50
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• 2002

The displacemant current measuring system used for detecting the dynamic behavior of monolayers at the air-water interface is described. It basically consists of a film balance, a pair of electrodes connected to each other through a sensitive ammeter. Here, one electrode is suspended in air and the other electrode is placed in the water. With Maxwell-displacement-current-measuring method, the phase transitons of $Poly-{\gamma}-benzyl_{L}$ -glutamate (PBLG) and $Poly-{\gamma}-benzyl_{D}$-glutamate(PBDG) on a water surface were detected. Measured surface pressure, displacement current and dipole moment of monolayers of PBLG and PBDG on the water surface. Also, we measured that compression velocity (30, 40, 50[mm/min]) when the sample spread volume was about 370[ul]-400[ul] and displacement current that occur when differed temperature. From the result, it is known that current is generated in the range of high surface pressures as compression velocity become faster and increase of temperature.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 1986년도 추계학술대회
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• pp.506-508
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• 1986

Metabolic activity of inorganic nitrogenous compounds affects not only microbial growth but also metabolite production in fermentation technology. We have worked on the enzymes participating in ammonia assimulation of some fermentation bacteria. This paper summarizes the results on glutamine synthetase and its application in practical field. Glutamine synthetase (L-glutamate:ammonia ligase, EC. 6.3.1.2) catalyzes the formation of glutamine from glutamate and ammonia at the expense of cleavage of ATP and inorganic phosphate. The enzyme plays a dual role in nitrogen metabolism in bacteria; it is a key enzyme not only in the biosynthesis of various compounds through glutamine but also in the regulation of synthesis of some enzymes involved in the metabolism of nitrogenous compounds. The detailed works with the Eschericia coli and other enterobacterial enzymes revealed that glutamine synthetase is controlled by the following complex of mechanisms: (a) feedback inhibition by end products, (b) repression and derepression of enzyme synthesis, (c) modulation of enzyme activity in response to divalent cation and (d) covalent modification of enzyme protein by adenylylation and its cascade control. Comparative studies have also been made on the enzymes from other organisms.

• Journal of Plant Biology
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• 제31권3호
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• pp.197-203
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• 1988

The rates of photorespiration and total CO2 fixation depending on leaf ages of spinach (Spinacia oleracea L.) were investigated. Metabolic rates of glycolate and glyoxylate in isolated peroxisomes were also measured. The rate of photorespiration and total CO2 fixation ability increased with the maturing of leaf, but decreased with senescence. Activities of enzymes involved in the peroxisomal photorespiratory pathway such as catalase, glycolate oxidase, NADH-glyoxylate reductase and glutamate-glyoxylate transaminase were highest in the mature leaf, but also decreased with aging of leaf. Glutamate-glyxolate transaminase activity significantly decreased with senescence, especially. the metabolic rate of glycolate was observed to be lower than that of glyoxylate in isolated peroxisomes. Glycolate seemed to be metabolized mainly to glycine, however, it also oxidized to CO2 when glycolate was supplied as a substrate for glycine synthesis instead of glyoxylate. The conversion rates of glycolate and glyxylate into CO2 increased with the senescence of leaves.

• Advances in Traditional Medicine
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• 제7권1호
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• pp.74-78
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• 2007

The plants, Trianthema decandra and Glinus oppositifolius are commonly used by tribal people in India for the treatment of liver diseases. Hepatoprotective activity of methanol extracts of Glinus oppositifolius and Trianthema decandra at the dose of 250 and 500 mg/kg body weight administered orally was evaluated against paracetamol induced liver damage in rats. Biochemical parameters such as serum glutamate oxaloacetate transaminase, serum glutamate pyruvate transaminase, serum alkaline phosphatase, bilirubin, total serum protein, lipid peroxide and glutathione content of the liver were estimated to determine liver function and metabolism. From the biochemical observations, it was concluded that methanol extracts of Glinus oppositifolius and Trianthema decandra significantly restored the altered biochemical parameters towards normal condition in paracetamol induced liver damage.

• Journal of Microbiology and Biotechnology
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• 제16권2호
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• pp.212-218
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• 2006

Three out of fourteen Microcystis-dominant cyanobacterial blooms in Central India were found to be toxic to mice ($LD_{50}$ ranging from 35-450 mg bloom dry mass/kg body weight). The liver architecture of the treated mice showed characteristic symptoms of hepatotoxicity relative to the untreated controls, with increased enzyme activities of serum lactate dehydrogenase (LDH), serum glutamate oxaloacetate transaminase (SGOT), alkaline phosphatase (ALP), and serum glutamate pyruvate transaminase (SGPT). RP-HPLC revealed the presence of microcystin-LR, microcystin-RR, and desmethyl microcystin-RR in the given region to maximum amounts of 390, 1,030, and $860{\mu}g/g$ bloom dry weight, respectively, corresponding to a maximum of 2.8 mg/l microcystin-LR in the lake water. Further confirmation of the microcystin variants was conducted using a MALDI-TOF MS analysis.

• Journal of Microbiology and Biotechnology
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• 제7권6호
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• pp.429-434
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• 1997

Macrolactin A, 24-membered macrolide, was isolated from the culture broth of Actinomadura sp. as a neuronal cell protecting substance. In the cell assay, this compound inhibited glutamate toxicity in N18-RE-105 cells with an $EC_50$ value of 0.5 ${\mu}g/ml.

• 한국식품영양과학회지
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• 제19권3호
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• pp.201-206
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• 1990

The optimal cultural conditions for production of the bluish purple prgment by the cultivation of Streptomyces californicus KS-89 were determined with various substrates. The carbon and nitrogen sources on the production of pigment indicated that soluble strarch and glycerol as carbon sources and sodium glutamate sodium nitrate as nitrogen sources given a mzimum yield of the pigment at 3$0^{\circ}C$ for 7 days. The addition of ferrous sulfate was essential. The highest production of pigment was observed with cultivation in a medium containing 2.0% soluble starch 1% glycerol 0.5% sodium glutamate 0.05% sodim nitrate 0.001% L-proline 0.025% K2HPO4 0.005% MgSO4 .7H2O, 0.04% FeSO4.7H2O, 0.001% thiamine.HCl and pH7.0.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.195.2-195.2
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• 2003

The CH$_2$Cl$_2$ fraction of the bark of Machilus thunbergii Sieb. et Zucc. (Lauraceae) significantly protected primary cultures of rat cortical cells exposed to the excitotoxic amino acid, L-glutamate. Several lignans including (-)-isoguaiacin, meso- dihydroguaiaretic acid, machilin A, (+)-galbelgin, licarin A, (-)-sesamin, and (+)-guaiacin were isolated from the CH$_2$Cl$_2$ fraction using by bioactivity-guided isolation techniques. Among these lignans, (-)-isoguaiacin, meso-dihydroguaiaretic acid, licarin A and (+)-guaiacin had significant neuroprotective activities against glutamate-induced toxicity in primary cultures of rat cortical cells at concentration ranging from 0.1 ${\mu}$M to 10.0 ${\mu}$M. (omitted)

• Journal of Chest Surgery
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• 제32권11호
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• pp.998-1003
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• 1999

Background: Bovine pericardium treated with glutaraldehyde(GA) is one of the most popular prosthetic materials. However, its late calcific degeneration after implantation results in early failure of the prosthesis. Therefore, we investigated the effects of combined treatment with sodium dodecyl sulfate(SDS) and glutamate on calcific degeneration of GA treated bovine pericardium. Material and Method: Sixty square-shaped pieces of bovine pericardia were fixed in 0.625% GA solution with 4g/L MgCl2.6H2O as a control group (group 1). Sixty pieces pretreated with 1% SDS (group 2) and sixty pieces posttreated with 8% glutamate (group 3) were also fixed in the same GA solution. Sixty pieces pretreated with 1% SDS and posttrated with 8% glutamate were also fixed in the same GA solution (group 4). After 1 month of fixation, the pieces were implanted into the belly of sixty Sprague-Dawley rat subdermally and were extracted 1 month, 2 months and 3 months after the implantation. With an atomic absorption spectrophotometry, we measured the calcium amount deposited. Result: The calcium deposition in 1 month was 2.01$\pm$0.13 mg/g in group 1, 1.45$\pm$0.31 mg/g in group 2, 2.49$\pm$0.15 mg/g in group 3 and 0.75$\pm$0.27 mg/g in group 4. In 2 months, it was 3.57$\pm$0.15 mg/g in group 1, 0.98$\pm$0.30 mg/g in group 2, 3.46$\pm$0.12 mg/g in group 3, and 1.48$\pm$0.39 mg/g in group 4, and 5.45$\pm$0.42 mg/g in group 1, 2.43$\pm$0.53 mg/g in group 2, 4.20$\pm$0.55 mg/g in group 3, and 1.02$\pm$0.27 mg/g in group 4 in 3 months. The calcium depositions in group 2 and 4 were less than those of group 1 and 3 in 1 month 2, months, and 3 months(p<0.01). The calcium depositions in group 1, 2 and 3 increased with time. However, they remained unchanged in group 4, which was statistically significant(p<0.01). Conclusion: Pretreatment with SDS is effective in reducing calcification of GA treated bovine pericardium, and the combined method of pretreatment with SDS and posttreatment with glutamate was more effective than the other methods.