• Title/Summary/Keyword: Biochemistry

검색결과 8,473건 처리시간 0.032초

Moderately thermostable phage Φ11 Cro repressor has novel DNA-binding capacity and physicochemical properties

  • Das, Malabika;Ganguly, Tridib;Bandhu, Amitava;Mondal, Rajkrishna;Chanda, Palas K.;Jana, Biswanath;Sau, Subrata
    • BMB Reports
    • /
    • 제42권3호
    • /
    • pp.160-165
    • /
    • 2009
  • The temperate Staphylococcus aureus phage ${\Phi}11$ harbors cI and cro repressor genes similar to those of lambdoid phages. Using extremely pure ${\Phi}11$ Cro (the product of the ${\Phi}11$ cro gene) we demonstrated that this protein possesses a single domain structure, forms dimers in solution at micromolar concentrations and maintains a largely $\alpha$-helical structure even at $45^{\circ}C$. ${\Phi}11$ Cro was sensitive to thermolysin at temperatures ranging from $55-75^{\circ}C$ and began to aggregate at ${\sim}63^{\circ}C$, suggesting that the protein is moderately thermostable. Of the three homologous 15-bp operators (O1, O2, and O3) in the ${\Phi}11$ cI-cro intergenic region, ${\Phi}11$ Cro only binds efficiently to O3, which is located upstream of the cI gene. Our comparative analyses indicate that the DNA binding capacity, secondary structure and dimerization efficiency of thermostable ${\Phi}11$ Cro are distinct from those of P22 Cro and $\lambda$ Cro, the best characterized representatives of the two structurally different Cro families.

목재부후균으로부터 Laccase 효소의 생산 및 유도 (Appearance of Laccase in Wood - Rotting Fungi and Its Inducibility)

  • 안드레 레오노비취;리리아나 지안프레다;죠오지 로갈스키;마그다 야색;욜란타 루테랙;마리아 바실레브스카;엘리지베타 말라책;안드레 다비도비취;모니카 핑크브츠;그리지나 기날스카;마그다 스타스책;조남석
    • Journal of the Korean Wood Science and Technology
    • /
    • 제25권3호
    • /
    • pp.29-36
    • /
    • 1997
  • 목재부후균으로 부터 락케이스 효소의 생산 및 유도를 위하여 여러가지 유도약품(inducer)을 사용하였다. 이들 가운데 ferulic acid, pentachlorophenol 및 2,5-xylidine이 매우 높은 락케이스 활성을 나타나게 하였으며, 거의 동일한 유도효과를 보여주었다. 이들 약품 이외에도 sinapic acid, syringic acid 및 coffeic acid 등도 높은 락케이스 활성을 주었는데, 산의 형태가 알데히드류보다도 높은 유도효과를 나타냈다. 그리고 실험한 48개 균주 가운데 38개 균주가 락케이스를 생산하였으며, 이 가운데 32균주가 ferulic acid에 의해 강한 효소유도 활성을 보였다. 이러한 결과는 지금까지 락케이스 효소의 검출이 어려웠던 Abortiporus biennis 및 Gleophyllum odoratum에서도 높은 락케이스 효소의 유도를 가능하게 하였다. 아울러 가장 높은 효소활성을 나타낸 균주로서는 Cerrena unicolor 였으며, 그 락케이스 효소활성이 무처리 및 inducer 첨가시 각각 40,000 및 60,000 nkat/l 정도였다.

  • PDF

ERRATUM

  • Le, Minh Ha;Do, Thi Thanh Huyen;Phan, Van Kiem;Chau, Van Minh;Nguyen, Thi Hong Van;Nguyen, Xuan Nhiem;Bui, Huu Tai;Pham, Quoc Long;Bui, Kim Anh;Kim, Seung Hyun;Hong, Hye-Jin;Kim, Sohyun;Koh, Young-Sang;Kim, Young Ho
    • Bulletin of the Korean Chemical Society
    • /
    • 제34권7호
    • /
    • pp.2218-2218
    • /
    • 2013

Isolation and Characterization of a cDNA for a Ribulose-1,5-Bisphosphate Carboxylase Small Subunit in Spinach

  • Jin, Yun-Hae;Park, Yang-Seo;Jeong, Ji-Na;Cho, Tae-Ju;Cho, Nam-Jeong
    • BMB Reports
    • /
    • 제30권3호
    • /
    • pp.173-176
    • /
    • 1997
  • We isolated a cDNA clone that encodes a ribulose-1,5-bisphosphate carboxylase small subunit (rbcS) from spinach using a soybean rbcS cDNA as a probe. The small subunit consists of 180 amino acids including a transit peptide of 57 residues. Comparison of the amino acid sequence with those of other plant species shows a maximum of 70-80% identical residues. Southern blot analysis suggests the existence of multiple rbcS genes in the spinach genome. Northern blot analysis indicates that the rbcS gene is expressed predominantly in leaves and that the expression of the gene is induced by light.

  • PDF

A Method for Evaluation of the Quality of DNA Microarray Spots

  • Zhang, Bao;Ma, Wen-Li;Hu, Zi-You;Shi, Rong;Song, Yan-Bin;Zheng, Wen-Ling
    • BMB Reports
    • /
    • 제35권5호
    • /
    • pp.532-535
    • /
    • 2002
  • To establish a method to evaluate the quality of the printed microarray and DNA fragments' immobilization. The target gene fragments that were made with the restriction display PCR (RD-PCR) technique were printed on a superamine modified glass slide, then immobilized with UV cross-linking and heat. This chip was hybridized with universal primers that were labeled with cy3-dUTP, as well as cDNA that was labeled with cy3-dCTP, as the conventional protocol. Most of the target gene fragments on the chip showed positive signals, but the negative control showed no signal, and vice versa. We established a method that enables an effective evaluation of the quality of the microarrays.

Potentiation of Ceramide-Induced Apoptosis by $p27^{kip1}$ Overexpression

  • Kim Hae Jong;Ghil Kyung Chul;Kim Moo Sung;Yeo Seong Hyun;Chun Young Jin;Kim Mie Young
    • Archives of Pharmacal Research
    • /
    • 제28권1호
    • /
    • pp.87-92
    • /
    • 2005
  • The cyclin-dependent kinase inhibitor$p27^{kip1}$(p27) has been implicated in the regulation of cell cycle and apoptosis. Recently, we have demonstrated that ceramide induces apoptotic cell death associated with increase in the level of p27 in HL-60 cells. In the present study, we showed that overexpression of p27 increases ceramide-induced apoptotic cell death in HL-60 cells. Furthermore, overexpression of p27 accelerated DNA fragmentation, PARP cleavage and cytochrome c release induced by ceramide. In addition, ceramide induced Sax expression independent of p27. These findings indicate that enhanced effect on apoptosis by p27 is associated with mitochondrial signaling which involves cytochrome c release.

Thermal Dissociation and Conformational Lock of Superoxide Dismutase

  • Hong, J.;Moosavi-Movahedi, A.A.;Ghourchian, H.;Amani, M.;Amanlou, M.;Chilaka, F.C.
    • BMB Reports
    • /
    • 제38권5호
    • /
    • pp.533-538
    • /
    • 2005
  • The kinetics of thermal dissociation of superoxide dismutase (SOD) was studied in 0.05 M Tris-HCl buffer at pH 7.4 containing $10^{-4}\;M$ EDTA. The number of conformational locks and contact areas and amino acid residues of dimers of SOD were obtained by kinetic analysis and biochemical calculation. The cleavage bonds between dimers of SOD during thermal dissociation and type of interactions between specific amino acid residues were also simulated. Two identical contact areas between two subunits were identified. Cleavage of these contact areas resulted in dissociation of the subunits, with destruction of the active centers, and thus, lost of activity. It is suggested that the contact areas interact with active centers by conformational changes involving secondary structural elements.

HDAC3 acts as a negative regulator of angiogenesis

  • Park, Deokbum;Park, Hyunmi;Kim, Youngmi;Kim, Hyuna;Jeoung, Dooil
    • BMB Reports
    • /
    • 제47권4호
    • /
    • pp.227-232
    • /
    • 2014
  • Histone deacetylase-3 (HDAC3) is involved in cellular proliferation, apoptosis and transcriptional repression. However, the role of HDAC3 in angiogenesis remains unknown. HDAC3 negatively regulated the expression of angiogenic factors, such as VEGF and plasminogen activator inhibitor-1 (PAI-1). HDAC3 showed binding to promoter sequences of PAI-1. HDAC3 activity was necessary for the expression regulation of PAI-1 by HDAC3. VEGF decreased the expression of HDAC3, and the down-regulation of HDAC3 enhanced endothelial cell tube formation. HDAC3 negatively regulated tumor-induced angiogenic potential. We show the novel role of HDAC3 as a negative regulator of angiogenesis.

THE NEW FINDING OF A LIGHT DEPENDENT $Ca^{2+}$ CHANNEL AND $Na^+-Ca^{2+}$ EXCHANGER IN THE VERTEBRATE RETINA (II)

  • Kim, Yun-Sook;Jung, Hyuk;Park, Chang-Suck;Woo, Suk-Hyang;Kim, Hyun-Jung;Kim, You-Young
    • Journal of Photoscience
    • /
    • 제3권3호
    • /
    • pp.133-136
    • /
    • 1996
  • Calcium modulates the activity of guanylate cyclase and plays a key role in dark and light adaptation in the visual system. We have measured the Ca$^{2+}$, K$^+$ and Na$^+$ concentration in dark and light adapted bullfrog's (Rana catesbeiana) vitreous humor by using the atomic absorption spectrophotometer. The calcium concentration of the light adapted bullfrog's vitreous humor was higher than that of the dark adapted bullfrog's vitreous humor. This means that ion activity between the photoreceptor and vitreous humor side is light dependent and we have found that a Ca$^{2+}$ channel and Na$^+$ - Ca$^{2+}$ exchanger exist in the vitreous humor.

  • PDF