• 한국미생물·생명공학회지
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• 제23권2호
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• pp.131-137
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• 1995

The alkaline phosphatase (K-ALPase) gene of Kluyveromyces fragilis has been cloned (1) and determined its base sequences (2) previously in our laboratory. When the K-ALPase gene was expressed in Escherichia coli and Saccharomyces cerevisiae, it showed a constitutive activity in E. coli, and a derepressed activity in S. cerevisiae in phosphate-limited medium. Northem hybridization experiment was performed to elucidate the transcription level of the K-ALPase gene. Northern experiment showed that transcription level of K-ALPase gene in S. cerevisiae was higher in phosphate depletion, but it was higher in high phosphate medium than in phosphate limited medium in K. fragilis. The transcription initiation site of the K-ALPase gene was determined by primer extension analysis. It matched nucleotide position - 169 in relation to the putative trnslational start site.

• Journal of Microbiology
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• 제45권4호
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• pp.311-317
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• 2007

In this study, the effects of phosphate concentration and carbon source on the patterns of alkaline phosphatase (APase) and phospholipase (PLase) expression in Vibrio vulnificus ATCC 29307 were assessed under various conditions. The activities of these enzymes were repressed by excess phosphate (4 mM) in the culture medium, but this repression was reversed upon the onset of phosphate starvation in low phosphate defined medium (LPDM) containing 0.2 mM of phosphate at approximately the end of the exponential growth phase. The expressions of the two enzymes were also influenced by different carbon sources, including glucose, fructose, maltose, glycerol, and sodium acetate at different levels. The APase activity was derepressed most profoundly in LPDM containing fructose as a sole carbon source. However, the repression/derepression of the enzyme by phosphate was not observed in media containing glycerol or sodium acetate. In LPDM-glycerol or sodium acetate, the growth rate was quite low. The highest levels of PLase activity were detected in LPDM-sodium acetate, followed by LPDM-fructose. PLase was not fully repressed by high phosphate concentrations when sodium acetate was utilized as the sole carbon source. These results showed that multiple regulatory systems, including the phosphate regulon, may perform a function in the expression of both or either APase and PLC, in the broader context of the survival of V. vulnificus.

• 한국표면공학회지
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• 제44권3호
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• pp.82-88
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• 2011

A uniform chromium-free conversion coating treated with an alkaline phosphate- permanganate solution was formed on the AZ 31 magnesium alloy. The effect of acid pickling on the morphology and on the corrosion resistance of the alkaline phosphate-permanganate conversion coating was investigated. The chemical composition and phase structure of conversion coating layer were determined via optical microscopy, SEM, EDS, XPS and XRD. Results show that the conversion coatings are relatively uniform and continuous, with thickness 1.8 to $2.4\;{\mu}m$. The alkaline phosphate-permanganate conversion coating was mainly composed of elements Mg, O, P, Al and Mn. The conversion-coated layers were stable compounds of magnesium oxide and spinel ($MgAl_2O_4$). These compounds were excellent inhibitors to corrosion. The electrochemical corrosion behaviors of coatings in 3.5 wt.% NaCl solutions were evaluated by electrochemical impedance spectroscopy, potentiodynamic polarization technique. EIS results showed a polarization resistance of $0.1\;k{\Omega}$ for the untreated Mg and $16\;k{\Omega}$ for the alkaline phosphate-permanganate conversion treatment sample, giving an improvement of about 160 times. The results of the electrochemical measurements demonstrated that the corrosion resistance of the AZ 31 magnesium alloy was improved by the alkaline phosphate-permanganate conversion treatment.

• 미생물학회지
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• 제23권2호
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• pp.90-100
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• 1985

The present study was designed to investigate cellular regulation of phosphate metabolism between catabolically repressed and derepressed states in yeast (Saccharomyces uvarum). The activities of various phospatases and the contents of phosphate compounds were detected according to the culture phase and various phosphate concentrations. As the results, Saccharomyces uvarum derepressed many phosphate metabolizing enzymes such as alkaline phosphatase, acid phosphatase and ATPase more than ten fold simultaneously during catabolic repression (phospgate and sugar starvation). At the same state, the amounts of orthophosphate, nucleotidic labile phosphate and acid soluble polypgosphate were increased, compared to basal levels of normally cultivated cells. $Mg^{++}-stimulated$ type among all phospatases was appeared to have most of the enzyme activity. It could be postulated that $K^+ -stimulated$ alkaline phosphatase was directly or indirectly correlated with the synthesis of acid insoluble polyphosphate $Mg^{++}-stimulated$ phosphatase with the degradation of polyphosphates. In case of cultivation in the medium supplemented with sugar and phosphate (catabolic derepression), phospgatase activities except for alkaline phosphatase were decreased rapidly through the progressive batch culture, After 12 hrs culture, at early exponential phase, the cellular accumulation of acid insoluble polyphosphate increased about 5 fold, compared to those of the starved cells. Under catabolic repression, it could be postulated that intracellular phosphate metabolism was regulated by derepressions of phosphatases. The function of polyphosphate system was shown to compensate the ATP/ADP system as phosphate donor and energy source especially during catabolic repression.

• 한국토양비료학회지
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• 제49권1호
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• pp.44-52
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• 2016

Plants response to phosphate starvation include the changes of activity of some enzymes, such as phosphatases, fructose-1,6-bisphosphatase, sucrose-phosphate synthase and nitrate reductase. In this study, to determine the effects of phosphate starvation on the change of activities of acid and alkaline phosphatase, fructose-1,6-bisphosphatase, sucrose-phosphate synthase, and nitrate reductase were studied in melon seedlings (Cucumis melo L.). The content of the protein and chlorophyll tended to relatively reduced in melon seedlings subjected to phosphate starvation. Acid phosphatase activity in first and second leaves of melon seedlings was relatively higher than that of third and fourth leaves of seedlings in 14 days after phosphate starvation treatment, respectively. Active native-PAGE band patterns of acid phosphatase in melon leaves showed similar to activities of acid phosphatase, whereas alkaline phosphatase activity was different from the change in the activity of acid phosphatase. Inorganic phosphate content in melon seedlings leaves was constant. The changes of Fructose-1,6-bisphosphatase and sucrose phosphate synthase activities showed similar patterns in melon seedlings leaves, and between these enzymes activities and phosphate nutrition negatively related. Fructose-1,6- bisphosphatase and sucrose phosphate synthase activities showed significant difference in second and fourth leaves, but nitrate reductase showed significant difference in first and second leaves in 14days after phosphate starvation treatment. We concluded that phosphate nutrition could affect the distribution of phosphate, carbon and nitrogen in melon seedlings.

• 한국임상약학회지
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• 제9권1호
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• pp.62-65
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• 1999

Inorganic phosphate (Pi) in rabbit plasma was found to block completely phosphotyrosine phosphatase (PTPase) activity without affecting the alkaline phosphatase (ALPase) activity. Our results provided that (1) PTPase activity and inhibitor are separated after G-25 gel-filtration. (2) This inhibitor is heat stable and trypsin-resistant and it can be removed by dialysis using 3 Kd cut-off tubing. (3) The elution pattern of the inhibitor is identical to that of Pi, and by performing a seperate run with inorganic phosphate. (4) The PTPase activity was recovered following an incubation with $CaCl_2$ (10 mM).

• 한국동물학회지
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• 제25권2호
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• pp.71-80
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• 1982

中國産 집오리, Anas platyrhynchos의 肝 alkaline phosphatase의 特性에 대해 觀察하여, 다음과 같은 結果를 얻었다. 1. 이 酵素는 分子의 크기가 다른 2가지 酵素種을 가짐을 보였다. 各 酵素分子는 各各 電氣泳動 速度가 다른 2가지 分子로 이루어 짐을 알았다. 2. 이 효소의 最適 pH는 9.0임이 판명되었고, 다른 포유류 酵素에 比해 熱에 대한 安定度가 낮았다. 3. $Mg^2+$은 이 酵素의 活性을 약 2배 증가 시켰으나, $Ca^2+$은 活性에 거의 影響을 주지 않았다. 4. Phosphate 이온은 이 효소에 대해 competitive, L-phenylalanine은 uncompetitive 阻害劑로 作用함을 알았다.

• 한국축산시설환경학회지
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• 제18권sup호
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• pp.13-20
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• 2012

연구는 양돈분뇨의 액비화 처리과정 중 농지환원 직전단계인 액비 후숙처리 단계에 있어서 $SCOD_{Mn}$ 농도 및 산도(pH)의 조정이 후숙액비의 이화학적성상에 미치는 영향을 알아보고 적절한 후숙 액비화 공정을 구축하기 위하여 수행하였으며, 실험결과를 요약하면 다음과 같다. 1. $SCOD_{Mn}$ 감소율은 알칼리발효 처리구에서 평균 29.9%, 인산중성화 처리구에서는 평균 36.9%로 인산 중성화 처리구가 비교적 높은 감소율을 보였다. 2. 30일간 처리 후 $SCOD_{Mn}$의 농도가 가장 낮은 처리구는 유입농도가 가장 낮았던 인산 중성화 처리구 T-6이다. 후숙 액비의 목표수준을 $SCOD_{Mn}$ 3,000 ppm 이하로 가정할 경우 후숙 발효조의 초기 투입농도는 5,500 ppm 이하로 조정하는 것이 적합하다고 사료된다. 3. 질소의 잔존율은 알칼리발효 처리구에서 평균 29.3%, 인산중성화 처리구에서 평균 38.9%로 인산중성화 처리구가 비교적 질소의 손실이 적은 한편, T-P의 경우 인산중성화 처리구에서 높은 농도(평균 1,473 ppm)로 유지되었다. 4. 본 연구를 통해 액비 후숙처리 시 '저인산-저질소'의 형태는 "알칼리발효 처리구", '고인산-고질소'의 형태는 "인산중성화 처리구"의 조건이 유리할 것으로 기대된다.

• Applied Biological Chemistry
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• 제38권5호
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• pp.376-381
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• 1995

내열성 alkaline phosphatase의 탐색을 위해 극도호열균중에서 Thermus caldophilus GK24 균주를 선정하였다. 이 균주를 이용하여 basal salts에 sodium glutamate, bactotryptone, glucose 및 yeast extract를 첨가시킨 배지에서 alkaline phosphatase 생산을 검토하였다. 그 결과 sodium glutamate가 alkaline phosphatase 유도에 효과적인 것으로 판명되었다. Alkaline phosphatase 생산을 위한 최적유도용 배지는 basal salts에 0.3% sodium glutamate, 0.2% bactotryptone, 0.5% glucose를 첨가한 것으로 효소활성은 기본배지보다 약 6배, 표준배지 보다는 약 27.5배 증가하였다. T. caldophilus GK24 alkaline phosphatase는 유도효소로 판명되었다. 무기인산 결핍시에 효소가 생산되며, 생육배지에 무기인산을 첨가하면 효소합성에 저해효과가 있었다.

• 약학회지
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• 제37권6호
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• pp.571-576
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• 1993

The substrate specificity of the purified rabbit plasma alkaline phosphatase (ALPase) was determined towards a extended range of potential substrates including relatively simple phosphate derivatives as p-NPP and indolyl phosphate, and several synthetic peptides and phosphoproteins. These results further estabilish the broad substrate specificity of these circulating enzymes. Interestingly, the plasma ALPase preferentially dephosphorylates Thr over Ser residues, as demonstrated with a series of synthetic peptides. The latter result is in contradiction to the behaviour of the tissue ALPase, which is thought to the ultimate source of plasma ALPase, and open therefore new perspectives with respective to the origin and "solubilisation" processes of these enzymes. Dephsphrylation of protein substrates by endogenous and isolated plasma ALPases indicates that ALPase probably displays protein phosphatase activity in vivo.