• Title/Summary/Keyword: serpin

Search Result 30, Processing Time 0.026 seconds

Conformational Properties of Disulfide-Free Recombinant Chicken Ovalbumin

  • Jeoung, Yeon-Hee;Yu, Myeong-Hee
    • BMB Reports
    • /
    • v.32 no.3
    • /
    • pp.247-253
    • /
    • 1999
  • Chicken egg ovalbumin is a non-inhibitory member of the serpin (serine protease inhibitors) family whose members share a common tertiary fold. In the present study, we succeeded in high-level production of a disulfide-free form of refolded recombinant ovalbumin. Conformational characterization of the recombinant ovalbumim revealed that it is well-folded, following two-state unfolding transition with the midpoint of transition at 4.7 M at $25^{\circ}C$. This value is very close to that of the reduced form of authentic ovalbumin. The recombinant ovalbumin can serve as a model molecule of non-inhibitory serpins in comparative studies with inhibitory members of the serpin family.

  • PDF

Differential Level of Host Gene Expression Associated with Nucleopolyhedrovirus Infection in Silkworm Races of Bombyx mori

  • Lekha, Govindaraj;Vijayagowri, Esvaran;Sirigineedi, Sasibhushan;Sivaprasad, Vankadara;Ponnuvel, Kangayam M.
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • v.29 no.2
    • /
    • pp.145-152
    • /
    • 2014
  • The variation in the level of immune response related gene expression in silkworm, Bombyx mori following infection with Bombyx mori nucleopolyhedrovirus (BmNPV) was analyzed at different time intervals. The occlusion bodies of BmNPV orally inoculated to the two most divergent silkworm races viz., Sarupat (resistant to BmNPV infection) and CSR2 (susceptible to BmNPV infection) were subjected to oral BmNPV inoculation. The expression profile of gp 41 gene of BmNPV in the Sarupat and CSR2 races revealed that the virus could invade the midguts of both susceptible and resistant races. However, its multiplication was significantly less in the midgut of resistant race, while, in the susceptible race, the viral multiplication reached maximum level within 12 h. These findings indicate that potential host genes are involved in the inhibition of viral multiplication within larval midgut. The immune response genes arylphorin, cathepsin B, gloverin, lebocin, serpin, Hsp 19.9, Hsp 20.1, Hsp 20.4, Hsp 20.8, Hsp 21.4, Hsp 23.7, Hsp 40, Hsp 70, Hsp90 revealed differential level of expression on NPV infection. The gloverin, serpin, Hsp 23.7 and Hsp 40 genes are significantly up-regulated in the resistant race after NPV infection. The early up-regulation of these genes suggests that these genes could play an important role in baculovirus resistance in the silkworm, B. mori.

CHARACTERIZATION OF A HUMAN $\alpha_1$-ANTITRYPSIN VARIANT THAT IS AS STABLE AS OVALBUMIN BUT RETAINS INHIBITORY ACTIVITY

  • Lee, Kee-Nyung;Yu, Myeong-Hee
    • Proceedings of the Korean Biophysical Society Conference
    • /
    • 1996.07a
    • /
    • pp.14-14
    • /
    • 1996
  • The metastable native state of proteins plays an important role in regulating biological functions. The native strain of serpins (serine protease inhibitors) are considered to be crucial for the inhibitory function. Several thermostable mutations of human $\alpha$$_1$-antitrypsin, a prototype inhibitory serpin, were identified in a systematic search targeted at the hydrophobic core of the molecule [Nature structural biology, vol. 3, no. 6, 497-500(1996)]. (omitted)

  • PDF

Regulation of the Inhibitory Function of $\alpha_1$-Antitrypsin by Native Metastability

  • Lee, Cheolju;Yu, Myeong-Hee
    • Proceedings of the Korean Biophysical Society Conference
    • /
    • 1999.06a
    • /
    • pp.41-41
    • /
    • 1999
  • The native forms of some proteins such as inhibitory serpins (serine protease inhibitors) and viral membrane fusion proteins are metastable, which is critical to their functions. To understand the mechanism of how native metastability regulates the inhibitory function of serpins, we characterized stabilizing mutations of $\alpha$$_1$-antitrypsin, a prototype serpin, in which Gly 117 was replaced by a series of larger hydrophobic residues.(omitted)

  • PDF

Engineering a Non-Inhibitory Serpin, Ovalbumin

  • Jeoung, Yeon-Hee;Yu, Myeong-Hee
    • Proceedings of the Korean Biophysical Society Conference
    • /
    • 1997.07a
    • /
    • pp.38-38
    • /
    • 1997
  • Serpins (serine protease inhibitor) are single polypeptide proteins of around 400 amino acids, and have a conserved secondary structure consisted of three ${\beta}$-sheets and nine ${\alpha}$-helices. Native conformation of inhibitory serpins is a metastable and requires conformational changes to inhibit target protease.(omitted)

  • PDF

Probing the Movement of Helix F of $\alpha_1$-Antitrypsin

  • Baek, Je-Hyun;Kim, Jun;Yu, Myeong-Hee
    • Proceedings of the Korean Biophysical Society Conference
    • /
    • 2002.06b
    • /
    • pp.31-31
    • /
    • 2002
  • $\alpha$$_1$-Antitrypsin is a member of the serine protease inhibitor (serpin) family that share a common tertiary structure. The reactive site loop (RSL) of serpins is exposed at one end of the molecule for protease binding. Upon cleavage by a target protease, the RSL is inserted into the major $\beta$-sheet A, which is a necessary process for formation of a tight inhibitory complex.(omitted)

  • PDF

A proteomic approach to identify yeast proteins responding to accumulation of misfolded proteins inside the cells

  • Shin, Yong-Seung;Seo, Eun-Joo;Kim, Joon;Yu, Myeong-Hee
    • Proceedings of the Korean Biophysical Society Conference
    • /
    • 2003.06a
    • /
    • pp.57-57
    • /
    • 2003
  • In growing number of diseases it has been shown that aggregation of specific proteins has an important role in pathogenesis of the disorder. This has been demonstrated in structural details with the liver cirrhosis of ${\alpha}$$_1$-antitrypsin deficiency, and it is now believed that similar protein aggregation underlies many neurodegenerative disorders such as autosomal dominant Parkinson disease, prion diseases, Alzheimer disease, and Huntington disease. ${\alpha}$$_1$-Antieypsin, a member of serine pretense inhibitor (serpin) family, functions as an inhibitor of neutrophil elastase.

  • PDF

Functional Role of the Native Strain that is Distributed throughout an <$\alpha_1$-antitrypsin

  • Seo, Eun-Joo;Yu, Myeong-Hee
    • Proceedings of the Korean Biophysical Society Conference
    • /
    • 2001.06a
    • /
    • pp.31-31
    • /
    • 2001
  • The native strain of serpins (serine protease inhibitors) has been recognized as a mechanism of biological regulation. Indeed, some stabilizing single residue mutations of human $\alpha$$_1$-antitrypsin, a prototype serpin, relieved local strain and caused the loss of inhibitory activity. The native strain of $\alpha$$_1$-antitrypsin is distributed throughout the whole molecule, but the strain that regulates the function directly is highly localized in the regions that appear to be mobilized during complex formation with a target protease.(omitted)

  • PDF