Journal of Insect Biotechnology and Sericology
Online ISSN : 1884-7978
Print ISSN : 1346-8073
ISSN-L : 1346-8073
71 巻, 2 号
選択された号の論文の4件中1~4を表示しています
  • Kenji Sato, Hiromasa Tanaka, Yoshimi Saito, Koichi Suzuki
    2002 年 71 巻 2 号 p. 69-77
    発行日: 2002/06/28
    公開日: 2010/02/25
    ジャーナル フリー
    A diapause-specific conotoxin-like peptide, diapausin, of the adult leaf beetle, Gastrophysa atrocyanea, was produced by the baculovirus/Bombyx mori system. Recombinant diapausin secreted in the blood plasma was purified by a combination of acidic-methanol extraction and reverse-phase high performance liquid chromatography. Matrix-assisted laser desorption ionization-time-of-flight mass spectrometry analysis indicated that the molecular mass (4463.3±4.5Da) of the recombinant diapausin agreed practically with the theoretical molecular mass (4467.6Da) calculated from the amino acid sequence of natural diapausin. The recombinant diapausin inhibited the growth of five tested species of phytopathogenic fungus including Fusarium solani, but was not active on two tested species of entomopathogenic fungus. For any of the tested phytopathogenic fungi, recombinant diapausin did not inhibit spore germination but diminished mycelial growth. The antifungal activity against F. solani was reduced by cations such as K+ and Ca2+, indicating cation-sensitive antifungal activity of this peptide. Recombinant diapausin was not active on four tested species of bacterium (i. e., one Gram-positive and three Gram-negative bacteria).
  • Kazuya Kozuma, Kunikatsu Hamano
    2002 年 71 巻 2 号 p. 79-83
    発行日: 2002/06/28
    公開日: 2010/02/25
    ジャーナル フリー
    The baculovirus expression vector system is widely utilized as a highly efficient protein production system, which in conjunction with the silkworm, Bombyx mori, is expected to be useful for commercial mass production of proteins. However, efficient mass production using baculovirus vector requires optimization of production conditions including the host condition, virus dose, and harvest time. Using a recombinant baculovirus encoding human serum albumin (HSA), a B. mori cell line (BmN-4) and B. mori larvae, we determined the effect of virus dose on recombinant HSA (rHSA) production and profile. The relationship between the virus dose and rHSA production in vitro (BmN-4 cells) was opposite that in vivo (B. mori larvae). in vitro, rHSA production increased proportionally with the inoculation virus dose and in vivo, rHSA production was inversely related to the virus dose. We also established that virus dose influenced the production profile and determined the optimum harvest time in vitro (72h postinfection) and in vivo (96h postinfection).
  • Hajime Miyake, Hiroyuki Wakisaka, Masanobu Nagura
    2002 年 71 巻 2 号 p. 85-89
    発行日: 2002/06/28
    公開日: 2010/02/25
    ジャーナル フリー
    A Poly (vinyl alcohol) (PVA)/sericin blended plastic with a high tenacity and biodegradability was prepared by melting molding, and the relationship between the structure and the physical properties of the plastic was studied. For a sericin content rate of 2wt%, the stress and strain increase. At 5wt% these values decrease, and at 10wt% or above they increase again. FT-IR spectra of the sericin shows an absorption peak at an amide I absorption band having a β sheet (1620cm-1). The blended plastic at a sericin content rate of below 20wt% shows an absorption peak at an amide I absorption band having a random coil (1652cm-1). On the other hand, at a sericin content rate of a 30wt%, sample shows both absorption bands. Further, in the dependence of tan δ on temperature, a new peak of the sample with over 10wt% sericin content rate was observed. For a sericin content rate of above approximately 10wt%, the excessive sericin phase separates from PVA. In this case, the strain of the sample increases from plastically deformed phase-separated sericin and consequently, the stress increases. At a sericin content rate of 2wt%, a good degree of the blended complex developed.
  • Lun Bai
    2002 年 71 巻 2 号 p. 91-95
    発行日: 2002/06/28
    公開日: 2010/02/25
    ジャーナル フリー
    Using the random walk model to describe the intervals of feeding ends in the fixed size reeling process, we proved that through the characteristic function, the distribution of intervals of the feeding ends is a Gamma distribution. This revealed the relationship of the distribution parameters with cocoon properties and conditions of raw silk reeling process. The theoretical result was confirmed by computer simulation of the reeling process and its application to the control of the reeling process was discussed.
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