• Applied Biological Chemistry
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• 제38권6호
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• pp.485-489
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• 1995

T-flask와 air-lift 생물반응기를 이용하여 Autographa californica nuclear polyhedrosis virus (AcNPV)의 Tn5B1-4 세포에의 감염시 fatty acid 및 lipid, mannose, folic acid, $CaCl_2$등의 배지 첨가물이 재조합 ${\beta}-galactosidase\;({\beta}-gal)$ 생산에 미치는 영향을 조사하였다. Cholesterol, tocopherol, tricaprylin 또는 mannose를 첨가하거나 folic acid를 보강첨가 했을 때 AcNPV의 재조합 ${\beta}-gal$ 생산은 향상되었으나 $CaCl_2$의 보강 첨가는 ${\beta}-gal$ 생산을 높이는데 효과적이지 못했다. Air-lift 생물반응기에서 0.34 mM cholesterol, 2.2 mM mannose 및 0.045 M folic acid를 보강 첨가한 배지를 이용하였을 때 재조합 ${\beta}-gal$ 생산은 basal medium에 비해 약 2배 정도의 증진 효과가 있었다.

• 한국미생물·생명공학회지
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• 제21권5호
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• pp.504-510
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• 1993

The effect of AcNPV infection conditions such as serum concentration, pH, CaCl2, lysosomotropic agent, cell density at infection, agitation, aeration and nutritional supplementattion on recombinant protein production in Spodoptera frugiperda 21 cells was investigated using tissue culture flask, bottle and spinner flask. It was shown that serum, CaCl2, pH and cell density at infection affected recombinant production. The lysosomotropic agent did not significantly influence recombinant protein production.

• 한국미생물·생명공학회지
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• 제26권2호
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• pp.161-166
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• 1998

AcNPV에 대해 감수성을 보이는 파밤나방 세포주인 Se301 세포주의 AcNPV를 이용한 발현 벡터계에서의 유용성을 알아보기 위하여 Se301세포주에서 AcNPV의 감염 특성을 Sf-21 세포주에서와 비교하였다. 그 결과, 바이러스의 감염상은 두 세포주에서 거의 유사하였으나 감염 7일 후에 세포로부터 방출된 다각체의 비율은 Se301 세포주에서 훨씬 높았다. 또한 전체 다각체 생성율은 Se301 세포주에서 약간 높았지만 그 차이는 매우 근소하여 대체적으로 두 세포주에서 거의 비슷하였으나 생성된 다각체의 크기는 Se301세포주에서 더욱 컸다. 한편, 세포주나 바이러스의 증식율과는 무관하게 AcNPV에 의한 다각체 단백질의 발현량이 Se301 세포주에서 약 2.4배 높게 나타남으로써 Se301 세포주가 AcNPV를 이용한 발현 벡터계에서 숙주 세포로서 매우 유용하게 이용될 수 있음을 보여 주었다.

• 한국미생물·생명공학회지
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• 제18권6호
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• pp.660-661
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• 1990

Autographa californica nuclear polyhedrosis virus(AcNPV) L-1주의 extracellular nonoccluded virion (NOV)을 보관하는 방법을 연구하였다. AcNPV NOVs을 Spodoptera frugiperda cell line에 감염을 시킨 후에 배양액을 원심분리하여 AcNPV NOVs가 들어 있는 상등액을 취하여 $4^{\circ}C$에서 약 11년간 보관하였다. 보관되어 있는 AcNPV NOV을 Spodoptera frugiprda cell line에 재감염하여 관찰한 결과 NOVs의 감염과 증식이 정상적이었으며, NOV의 역가가 $8.9 \times 10^7$pfu/ml에서 $3.8 \times 10^5$pfu/ml로 떨어졌을 뿐이다. 또한 HindIII와 EcoRI 제한효소로 AcNPV genome DNA을 절단하여 패턴을 조사한 결과 DNA제한 효소 패턴은 변하지 않았다. 즉 AcNPV NOVs는 $4^{\circ}C$에서 보존하면 10년 이상 안정성이 있고, 취급이 용이하다는 것을 알 수 있었다.

• 한국잠사곤충학회지
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• 제41권2호
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• pp.102-107
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• 1999

To analysis a promoter strength of Atographa californica nucler polyhedrosis virus (AcNPV) IE1 gene, an immediate viral gene, ${\beta}$-glactosidase gene as a reporter gene was introduced under the control of the IE1 promoter. The restriction fragment containing IE1 promoter and ${\beta}$-galctosidase gene from pAcIE1-gal were inserter into pBacPAK9 to yield transfer vector pAcNPV-IE1-gal. The pAcNPV-IE1-gal was cotransfected with AcNPV genomic DNA BacPAK6 into Sf9 cells to produce recombinant baculovirus AcNPV-IE1-gal. In addition, recombinant bacvulovirus AcNPV-gal, which express ${\beta}$-galac-tosidase under the control of the polyhedrin promoter, was constrer, was constructed to compared with AcNPV-IE1-gal. The recombinant viruses were respectively infected into Sf9 cells and characterized by the virus titer and expression of ${\beta}$-galactoxidase in Sf9 cells. The promoter strength of IE1 and polyhedrin promoters was determined by the amount of ${\beta}$-galactosidase secreted into medium by viral infection. The titer of AcNPV-IE1-Gal determined by plaque assays in Sf9 cells was similar to that of AcNPV-gal. However, expression level of ${\beta}$-galactosidase by AcNPV-IE1-gal was significantly lower than that by AcNPV-gal. In conclusion, promoter strength of IE1 was approximately 25-fold lower than that of polyhedrin.

• KSBB Journal
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• 제9권3호
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• pp.294-298
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• 1994

$CaCl_2$, glucose, frutose, glutamine, glutamate 그리고 Ii pids와 같은 배지 첨가물들이 회분식 그리고 연속식 2단계 생물반응기 시스템에셔 재조합 ${\beta}$-galactosidase (${\beta}$-gal) 생산을 증진시키는가를 조사하였다. Sf 21 세포에 AcNPV의 감염시 $CaCl_2$, frutose, glutamate, cholesterol 및 tocoph eral과 같은 배지 첨가물을 첨가하였을 때 ${\beta}$-gal 생산이 증진되었다. 30mM $CaCl_2$, 2.2mM frutose, 4.lmM glutamine, 그리고 O.34mM cholesterol이 보강된 감염 배 지를 이용한 재조합${\beta}$-gal 생산은 약 40% 의 증가를 보였다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XII)
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• pp.315-319
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• 2003

A novel method is developed to yield virus titers in 10 h, is easy to .perform using 96-well plates, and applicable to both any Autographa californica nucleopolyhyderovirus (AcNPV) and Bombyx mori nucleopolyhedrovirus (BmNPV)-based recombinant baculovirus. This assay uses an antibody to a DNA-binding protein to detect the infected cells via immune-staining. The titer is determined by counting foci produced due to infection of virus under a fluorescent microscopy. The required incubation period was shortened considerably because infected cells expressed viral antigens at the post infection time of 4 h. Therefore, 10 hours were enough to estimate the virus titer including virus infection time, insect cell culture, and estimation of virus titer.

• International Journal of Industrial Entomology and Biomaterials
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• 제2권1호
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• pp.19-26
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• 2001

Transformed Spodoptera frugiperda (Sf9) cells expressing baculovirus very late factor (VLF-1) were constructed by using Autograha nuclear polyhedrosis virus (AcNPV) immediate earthy gene (ie1). Neomycin-resistance gene as a selectable marker was introduced under the control of AcNPV ie1 promoter, and Bombyx mori nuclear polyhedrosis (BmNPV-K1) vlf-1 gene was introduced under the control of the Drosophila heat shock protein gene (hspr70) promoter to yield dual expression plasmid with two independent transcription units. It was transfected into Sf9 cells and cell clones expressing vlf-1 were selected by G4l8 treatment. Genomic DNA from transformed cells was isolated and integration of AcNPV iel harboring vlf-1 was confirmed by PCR using AcNPV iel-specific primers and Southern blot analysis. The transformed cells expressing VLF-1 in an infection-independent manner expressed foreign gene product of recombinant baculovirus in the earlier stage of infection compared with control Sf9 cells. These results suggest the possible to develop highly efficient transformed insect cells for baculovirus expression vector system.

• 대한의생명과학회지
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• 제14권2호
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• pp.119-122
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• 2008

The baculovirus/insect cell expression system is of great value in the study of structure-function relationships in mammalian glucose-transport proteins by site-directed mutagenesis and for the large-scale production of these proteins for mechanistic and biochemical studies. In order to exploit this, the effects of substitution at the highly conserved residue glutamine 282 of the human erythrocyte-type glucose transporter have been examined by in vitro site-directed mutagenesis. The modified human transport protein has been expressed in Spodoptera frugiperda 21 cells by using the recombinant baculovirus AcNPV-GTL. To assess the functional integrity of the expressed transporter, measurements of the transport inhibitor cytochalasin B binding were performed, involving the membranes prepared from 4 days post infection with no virus, with wild-type virus or AcNPV-GTL virus. Data obtained showed that there was little or no D-glucose-inhibitable binding in cells infected with the wild type or no virus. Only the recombinant virus infected cells exhibited specific binding, which is inhibitable by D- but not by L-glucose. However, there was a notable reduction in the affinity for the potent inhibitor cytochalasin B when binding measurements of AcNPV-GTL were compared with those of AcNPV-GT, which has no substitution. It is thus suggested that although the modified and unmodified human transporters differed slightly in their affinity for cytochalasin B, the glutamine substitution did not interfere the heterologous expression of the human transporter in the insect cells.

• Journal of Microbiology
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• 제34권1호
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• pp.7-14
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• 1996

Teh baculovirus gp64 glycoprotein is a major component of the envelope of budded virus (BV) and has been shown that it plays an essential role in the infection process, especially virus-cell membrane fusion. We have cloned Autographa californica Nuclear Polyhedrosis Virus (AcNPV) gp64 protein were examined for membrane fusion activity by using a synchtium formation assay under various conditions. The optimal conditions required for inducing membrane fusion are 1) form pH 4.0 to 4.8 2) 15 min exposure of cells to acidic pH 3) at least 1 .mu.g of gp64 cloned plasmid DNA per 3 * 10$^{6}$ cells 4) and an exposure of cells to acidic pH at 72 h post-transfection. In order to investigate the role of hydrophobicity of the gp64 glycoprotein for the membrane fusion, the two leucine residues (amino acid position at 229 and 230) within hydrophobic region I were substituted to alanine by PCR-derived site-directed mutagenisis and the membrane fusion activity of the mutant was anlaysed. The gp64 glycoprotein carrying double alamine substitution mutation showed no significant difference in fusion activity. This result suggested that minor changes in hydrophobicity at the amino acid position 229 and 230 does not affect the acid-induced membrane fusion activity of the gp64 glycoprotein.