• Journal of Microbiology
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• 제37권1호
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• pp.21-26
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• 1999

Two novel calcium-binding proteins, named CAB-I and CAB-II, have been isolated from Streptomyces coelicolor. Purification of the calcium-binding proteins involved heat treatment, fractionation with ammonium sulfate, acid treatment, anion exchange and hydrophobic interaction column chromatography, FPLC gel filtration, and preparative isoelectric focusing. A chelex competitive assay and 45Ca autoradiography verified the calcium-binding ability of the proteins. The major band CAB-II has an apparent molecular weight of 26,000 determined by SDS-polyacrylamide gel electrophoresis and 340,000 determined by gel filtration. The isoelectric point of this molecule showed the acidic nature of the molecule. N-terminal amino acid sequence analysis shows homology to rat Ca2+/calmodulin-dependent protein kinase-II (CAB-II) and yeast phosphoprotein phosphatase (CAB-I).

• Journal of Microbiology and Biotechnology
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• 제22권7호
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• pp.1029-1033
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• 2012

A number of evidence have been accumulated that the regulation of reversible tyrosine phosphorylation, which can be regulated by the combinatorial activity of protein tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs), plays crucial roles in various biological processes including differentiation. There are a total of 107 PTP genes in the human genome, collectively referred to as the "PTPome." In this study, we performed PTP profiling analysis of the HIB-1B cell line, a brown preadipocyte cell line, during brown adipogenesis. Through RT-PCR and real-time PCR, several PTPs showing differential expression pattern during brown adipogenesis were identified. In the case of PTP-RE, it was shown to decrease significantly until 4 days after brown adipogenic differentiation, followed by a dramatic increase at 6 days. The overexpression of PTP-RE led to decreased brown adipogenic differentiation via reducing the tyrosine phosphorylation of the insulin receptor, indicating that PTP-RE functions as a negative regulator at the early stage of brown adipogenesis.

• Bulletin of the Korean Chemical Society
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• 제32권spc8호
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• pp.2883-2884
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• 2011

• Archives of Pharmacal Research
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• 제14권1호
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• pp.81-86
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• 1991

Dry powder and different extracts of Agave lophantha were tested against Biomphalaria alexandrina. The results showed that the butanol extract has high molluscicidal activity. The activity of the dry powder has been found to be stable under the effect of some simulated field conditions. Also the toxicological effect of the plant on mice was tested through determination of certain parameters such as total protein, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and acid phosphatase enzymes as well as histopathological study on liver and kidney.

• 한국미생물·생명공학회지
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• 제25권3호
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• pp.271-276
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• 1997

An ascorbic acid phosphorylating enzyme, which catalyzes the formation of ascorbic acid-2-phosphate from ascorbic acid and pyrophosphate, was purified 32.7-folds to homogeneity from a cell-free extract of Cellulomonas sp. AP-7. The combination of DEAE- Sephacel ion exchange chromatography and Sephacryl S-200 get filtration was used for their purification. The molecular weight of the native protein was estimated to be 96.lkDa on high performance gel filtration chromatography. The SDS-PAGE analysis indicated that the protein consisted of four identical subunits of 24.6 kDa. The purified enzyme showed the optimal tempeature of 40$\circ$C and optimal pH of 4.5. The Km for ascorbic acid and pyrophosphate were 119 mM and 11.9 mM, respectively. The addition of 5,5'-dithiobis-(2-nitrobenzoic acid) into the reaction mixture resulted in the reduction of the enzyme activity at 51%. The enzyme also had a phosphatase activity at weakly acidic pH and the Km for ascorbic acid-2-phosphate in phosphatase activity was 7.9 mM.

• Bulletin of the Korean Chemical Society
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• 제32권2호
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• pp.697-700
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• 2011

• BMB Reports
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• 제31권2호
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• pp.135-138
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• 1998

A previous study on a yeast protein tyrosine phosphatase, YPTP1, using synthetic phosphotyrosine-containing peptides with various sequences as substrates revealed that DADEpYDA exhibits high affinity ($K_m=4{\mu}M$) toward the enzyme. A modified version of this peptide, GDADEpmFDA, immobilized on a resin, was used in this study as an affinity ligand for the purification of YPTP1. Phosphonomethyl-phenylalanine (pmF) was used as a nonhydrolyzable analog of the phosphotyrosine (pY) residue, with properties similar to pY. A protected form of pmF, $Fmoc-pmF(^{t}Bu)_{2}-OH$, was chemically synthesized and introduced during solid-phase peptide sythesis. YPTP1 was onrexpressed in an E. coli strain carrying a plasmid pT7-7-ptpl. Affinity chromatography of the crude lysate afforded PTPI (39 kDa) of about 50% purity.

• Bulletin of the Korean Chemical Society
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• 제34권4호
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• pp.1023-1024
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• 2013

• Bulletin of the Korean Chemical Society
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• 제33권11호
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• pp.3772-3776
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• 2012

Mitogen-activated protein kinase phosphatase 4 (MKP4) has proved to be a promising target for the development of therapeutics for the treatment of diabetes and the other metabolic diseases. Here, we report an example for a successful application of the structure-based virtual screening to identify three novel inhibitors of MKP4. These inhibitors have desirable physicochemical properties as a drug candidate and reveal a moderate potency with $IC_{50}$ values ranging from 4.9 to $32.3{\mu}M$. Therefore, they deserve consideration for further development by structure-activity relationship studies to optimize the inhibitory and antidiabetic activities. Structural features relevant to the stabilization of the newly identified inhibitors in the active site of MKP4 are discussed in detail.

• KSBB Journal
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• 제7권1호
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• pp.39-44
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• 1992

다당류의 ICR 마우스에서 백혈구수와 복강세포수가 현저히 증가하였고, 면역 관련 장기의 무게도 용량에 따라 증가하는 용량 의존성 반응을 보였고, maerophage의 식작용에 미치는 영향은 phagocytic index와 corrected phagocytic index에서 거의 차이가 없었다. 다당류가 마우스의 혈액 중에 효소 활성 및 일반 생화학적 성분에 미치는 영향을 조사해 본 결과 S-GOT, S-GPT, alkaline phosphatase, total protein, albumin, globulin, Cholesterol, triglyceride, blood urea nitrogen 및 glucose는 대조군에 비하여 비슷한 수준을 나타내었다.