• Bulletin of the Korean Chemical Society
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• 제30권10호
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• pp.2485-2488
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• 2009

• 한국동물학회:학술대회논문집
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• 한국동물학회 2003년도 한국생물과학협회 학술발표대회
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• pp.162.2-162
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• 2003

No Abstract, See Full Text

• Journal of Microbiology and Biotechnology
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• 제12권2호
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• pp.301-305
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• 2002

The gene (ppaT) encoding Thermus caldophilus GK24 pyrophosphatase (Tca pyrophosphatase) was cloned and sequenced. The gene was found to contain an open reading frame encoding 175 amino acids with a calculated mass of 19,155 Da. The ppaT gene was expressed under the control of the tac promoter in Escherichia coli. The recombinant Tca pyrophosphatase was purified 21.4-fold with $56\%$ yield and specific activity of 25.7 U $mg^-1$, following a combination of heating (to denature the E. coli proteins) and one step of DEAE-Sephacel column chromatography. The native enzyme was found to have an approximate molecular mass of 110,000 Da and consisted of six subunits. The enzyme exhibited maximal activity at pH of 8.0-8.5 and was stable at $80-90^{\circ}C$. A divalent cation was absolutely required for the enzyme activity, with $Mg^2+$. being the most effective.

• BMB Reports
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• 제29권3호
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• pp.253-260
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• 1996

An enzyme that hydrolyzes flavin-adenine dinucleotide (FAD) was found to be present in rat liver lysosomal membrane prepared from Triton WR-1339 filled lysosomes (tritosomes) purified by flotation on sucrose. This FAD phosphohydrolase (FADase) exhibited optimal activity at pH 8.5 and had an apparent Km of approximately 3.3 mM. The activity was decreased 50~70% by dialysis against EDTA and this was restored by $Zn^{2+}$, $Mg^{+2}$, $Hg^{+2}$, and $Ca^{+2}$ ions inhibited the enzyme, but $F^-$ and molybdate had no effect. The enzyme was also inhibited by p-chloromercuribenzoate (pCMB), reduced glutathione and other thiols, cyanide, and ascorbate. The presence of ATP, ADP, AMP. ${\alpha}-{\beta}-methylene$ ATP, AMP-p-nitrophenyl phosphate (PNP), GMP, and coenzyme A (CoA) decreased the activity on FAD, but pyrimidine nucleotides, adenosine, adenine, or $NAD^+$ were without effect. Phosphate stimulated the activity slightly. FAD phosphohydrolase activity was separated from ATPase and inorganic pyrophosphatase activities by solubilization with detergents and polyacrylamide gel electrophoresis and by linear sucrose density gradient centrifugation suggesting that the enzyme is different from ATPase, inorganic pyrophosphatase, and soluble lysosomal FAD pyrophosphatase. Paper chromatography showed that FAD was hydrolyzed to flavin mononucleotide (FMN) and AMP which were further hydrolyzed to riboflavin and AMP by phosphatases known to be present in lysosomal membranes. Incubation of the intact Iysosomes with pronase showed that the active site of FAD phosphohydrolase must be oriented to the cytosol. The FAD hydrolyzing activity was detected in Golgi, microsome, and plasma membrane, but not in mitochondria or soluble lysosomal preparations.

• 환경생물
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• 제20권3호
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• pp.237-244
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• 2002

항진균 활성 관련 단백질을 탐색하기 위해 미역류로부터 식물병원성 곰팡이의 생장을 저해하는 SAR01 균주를 분리하였고, FAME (fatty acid methyl ester) 분석 결과, Streptomyces sp.로 동정되었다. 방사선 조사$(^{60}Co)$를 실시한 결과, Botrytis cinerea를 포함한 5종의 식물병원성 곰팡이에 대한 항진균 활성을 소실한 SAR535 균주 외 6종의 돌연변이 균주가 유도되었다. SAR01 야생형 균주와 SAR535 돌연변이 균주의 세포내 단백질의 이차원 전기영동 분석결과, 6종의 단백질이 야생형 균주인 SAR01 균주의 세포내에만 존재하였다. 이들 6종의 단백질 중, 5종은 heat shock protein 70 (HSP70), Fe-containing superoxide dismutase II (Fe - SODII), ribosome recycling factor (RRF), 10 kD chaperonin (GroES) 및 inorganic pyrophosphatase (PPAse)와 각각 75%, 93%, 100%, 96% 및 83%의 유사성을 보였다. 이들 6종의 단백질들은 Streptomyces sp. SAR01 균주의 항진균 활성과 밀접한 관계가 있을 것으로 사료된다.

• 한국토양비료학회지
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• 제15권4호
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• pp.241-250
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• 1982

발아초기 녹두의 부위별 alkaline inorganic PPase의 활성변화 및 잎 부위에서 부분 정제하여 얻은 효소를 이용하여 효소적 성질을 조사한 결과를 요약하면 다음과 같다. 1. 잎 부위가 타 부위보다 약 2~4배의 더 높은 활성을 나타냈으며 발아가 진행됨에 따라 잎과 뿌리 그리고 지엽에서는 효소 활성이 초기에 증가하다가 점차 감소하는 경향을 보인 반면, 상배축에서는 초기부터 계속 감소하였으며 하배축에서는 계속 증가하는 경향을 보였다. 2. 정제 과정동안 23.9%의 수율로 86배가 정제되었으며 전기 영동상의 Rm value는 0.35였으며 homogenenity는 아니었고, Km value는 0.89mM로 나타났다. 3. 이 효소는 $Mg^{2+}$에 대해 대단히 Specific하였으며 $Cu^{2+}$와 $Fe^{2+}$도 $Mg^{2+}$에 비해 각각 56%, 55%의 activating effect를 나타냈다. 그러나, $Cu^{2+}$, $Zn^{2+}$, $Mn^{2+}$, $Co^{2+}$와 $Ni^{2+}$은 이 효소에 대해 저해체로 작용하였다. 4. 이 효소는 pH 8-9와 $50^{\circ}C$에서 최대의 활성을 보였으며 열에 대해서도 상당히 안정하였다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.219-222
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• 2000

Physiological changes of Escherichia coli during the fed-batch fermentation process were characterized in this study. Overall cellular protein samples prepared at the different stage of fermentation were separated by 2-dimensional gel electrophoresis (2-DE), and differently expressed 15 proteins, Phosphotransferase enzyme I, GroEL, Trigger factor, ${\beta}$ subunit of ATP synthase, Transcriptional regulator KDGR, Phosphoglycerate mutase 1, Inorganic pyrophosphatase, Serine Hydroxymethyl-transferase, ${\alpha}$ subunit of RNA polymerase, Elongation factor Tu, Elongation factor Ts, Tyrosine-tRNA ligase, DnaK suppressor protein, Transcriptional elongation factor, 30S ribosomal protein S6 were identified using matrix-assisted laser desorption / ionization time-of-flight mass spectrometry (MALDI-TOF MS). When bacterial cells grow to high cell density, and IPTG-inducible heterologous protein is produced, expression level of overall cellular proteins was decreased. According to their functions in the cell, identified proteins were classified into three groups, proteins involved in transport process, small-molecule metabolism, and synthesis and modification of macromolecules.