The Experts below are selected from a list of 240 Experts worldwide ranked by ideXlab platform
Tai Hyun Park - One of the best experts on this subject based on the ideXlab platform.
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Enhanced production of recombinant protein inEscherichia coli using silkworm Hemolymph
Biotechnology and Bioprocess Engineering, 2005Co-Authors: Ji Eun Kim, Eun Jeong Kim, Won Jong Rhee, Tai Hyun ParkAbstract:The effect of silkworm Hemolymph on the expression of recombinant protein inEscherichia coli was investigated. The addition of silkworm Hemolymph to the culture medium increased the production of recombinant β-galactosidase inE. coli. The production was dependent on the concentration of the added silkworm Hemolymph, which increased 2-, 5-, and 8-fold in media supplemented with 1,3, and 5% silkworm Hemolymph, respectively. To identify the effective component, the silkworm Hemolymph was fractionated by gel filtration column chromatography. A fraction, with a molecular weight of about 30 K was identified as the effective component.
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Inhibition of human cell apoptosis by silkworm Hemolymph.
Biotechnology progress, 2002Co-Authors: Shin Sik Choi, Won Jong Rhee, Tai Hyun ParkAbstract:Many studies on preventing apoptosis have been carried out from the viewpoint of anti-apoptotic cloned-gene expressions inside cells, whereas in this study, we investigated the inhibition of apoptosis by the addition of silkworm Hemolymph, a natural compound, from outside of the cells. In a previous study, we reported the inhibition effect of silkworm Hemolymph on the baculovirus-induced insect cell apoptosis. Using the vaccinia virus-HeLa cell system as a model system in this study, we found that silkworm Hemolymph, the insect serum, inhibits apoptosis not only in the insect cell system but also in the human cell system. The vaccinia virus-induced HeLa cell apoptosis was analyzed using DNA electrophoresis, TUNEL, and flow cytometry, and the resulting data confirmed that silkworm Hemolymph inhibits human cell apoptosis. The inhibition of apoptosis due to silkworm Hemolymph was not caused by an inhibition of virus binding and internalization steps, nor did silkworm Hemolymph interfere with the virus production. The inhibition of apoptosis by silkworm Hemolymph decreased the cell detachment from an adhering surface. With these characteristics, silkworm Hemolymph can be effectively used to minimize cell death in commercial animal cell culture.
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Silkworm Hemolymph inhibits baculovirus-induced insect cell apoptosis.
Biochemical and biophysical research communications, 2000Co-Authors: Won Jong Rhee, Tai Hyun ParkAbstract:The effect of silkworm Hemolymph on baculovirus-induced insect cell apoptosis was investigated. The addition of silkworm Hemolymph into the culture medium either before or during the baculovirus infection increased the host cell longevity; however, its addition after the infection was less effective. This can be explained by the higher transfer rate of silkworm Hemolymph which is caused by endocytosis during the virus internalization step. The delayed cell death due to silkworm Hemolymph was not caused by an inhibition of the virus attachment and internalization steps. The apoptosis was analyzed using DNA fragmentation and TUNEL assays, and the resulting data confirm that silkworm Hemolymph inhibits baculovirus-induced insect cell apoptosis.
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Oxidation-deficient silkworm Hemolymph as a medium supplement for insect cell culture
Biotechnology and Bioprocess Engineering, 1998Co-Authors: Eun Jeong Kim, Ji-young Choi, Sam-eun Kim, Tai Hyun ParkAbstract:Hemolymph is oxidized and darkens visibly during the collection from silkworms due to the activity of tyrosinase in it. Toxic quinones are produced by the oxidation and consequently inhibit the cell growth. Heat treatment can be used to prevent the oxidation; however, the oxidation may occur during the collection of Hemolymph before it is heat-treated. It makes the Hemolymph collection difficult especially on a large-scale preparation. Hemolymphs collected from 257 different strains of silkworms were examined to select the slowly oxidized Hemolymphs. Hemolymphs collected from mutant strains such as Lemone, TBO, Cre, Y4, and wEb showed relatively slow color changes. Oxidation rates of the Hemolymphs were measured by the absorbance change using a spectrophotometer. The Hemolymph of wEb showed the slowest oxidation. The absorbance of this mutant Hemolymph reached the saturation value at 20°C in 450 min, whereas the total oxidation time of the wild-type (Baekokjam) Hemolymph at the same temperature was 120 min. We tested if this mutant Hemolymph is useful as a medium supplement for insect cell culture. Cell growth rate and final cell concentration in the medium supplemented with the wEb Hemolymph were almost same as those in the medium supplemented with the wild-type Hemolymph. Hemolymph is collected on a small scale by clipping the abdominal leg; however, this method is not appropriate for large scale preparation. Centrifugation after chopping the silkworm Hemolymph by a blending mixer is a more appropriate procedure for large scale collection. Slowly oxidized wEb Hemolymph resulted in higher cell concentration than the wild-type Hemolymph when Hemolymph was collected by the large scale preparation method.
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silkworm Hemolymph as a substitute for fetal bovine serum in insect cell culture
Biotechnology Techniques, 1996Co-Authors: Sung-ho Ha, Tai Hyun ParkAbstract:The effectiveness of silkworm Hemolymph was investigated as a substitute for fetal bovine serum (FBS) in insect cell culture. Cells were adapted to grow in reduced FBS medium supplemented with silkworm Hemolymph through a gradual adaptation process. FBS concentration in the medium could be reduced to 1% without decrease in cell growth rate and maximum cell concentration by adding 5% silkworm Hemolymph.
Lihong Zhou - One of the best experts on this subject based on the ideXlab platform.
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developmental changes for the Hemolymph metabolome of silkworm bombyx mori l
Journal of Proteome Research, 2015Co-Authors: Lihong Zhou, Fuhua Hao, Xin Liu, Guoliang Wang, Yulan Wang, Huiru TangAbstract:Silkworm (Bombyx mori) is a lepidopteran-holometabolic model organism. To understand its developmental biochemistry, we characterized the larval Hemolymph metabonome from the third instar to prepupa stage using (1)H NMR spectroscopy whilst Hemolymph fatty acid composition using GC-FID/MS. We unambiguously assigned more than 60 metabolites, among which tyrosine-o-β-glucuronide, mesaconate, homocarnosine, and picolinate were reported for the first time from the silkworm Hemolymph. Phosphorylcholine was the most abundant metabolite in all developmental stages with exception for the periods before the third and fourth molting. We also found obvious developmental dependence for the Hemolymph metabonome involving multiple pathways including protein biosyntheses, glycolysis, TCA cycle, the metabolisms of choline amino acids, fatty acids, purines, and pyrimidines. Most Hemolymph amino acids had two elevations during the feeding period of the fourth instar and prepupa stage. Trehalose was the major blood sugar before day 8 of the fifth instar, whereas glucose became the major blood sugar after spinning. C16:0, C18:0 and its unsaturated forms were dominant fatty acids in Hemolymph. The developmental changes of Hemolymph metabonome were associated with dietary nutrient intakes, biosyntheses of cell membrane, pigments, proteins, and energy metabolism. These findings offered essential biochemistry information in terms of the dynamic metabolic changes during silkworm development.
Huiru Tang - One of the best experts on this subject based on the ideXlab platform.
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developmental changes for the Hemolymph metabolome of silkworm bombyx mori l
Journal of Proteome Research, 2015Co-Authors: Lihong Zhou, Fuhua Hao, Xin Liu, Guoliang Wang, Yulan Wang, Huiru TangAbstract:Silkworm (Bombyx mori) is a lepidopteran-holometabolic model organism. To understand its developmental biochemistry, we characterized the larval Hemolymph metabonome from the third instar to prepupa stage using (1)H NMR spectroscopy whilst Hemolymph fatty acid composition using GC-FID/MS. We unambiguously assigned more than 60 metabolites, among which tyrosine-o-β-glucuronide, mesaconate, homocarnosine, and picolinate were reported for the first time from the silkworm Hemolymph. Phosphorylcholine was the most abundant metabolite in all developmental stages with exception for the periods before the third and fourth molting. We also found obvious developmental dependence for the Hemolymph metabonome involving multiple pathways including protein biosyntheses, glycolysis, TCA cycle, the metabolisms of choline amino acids, fatty acids, purines, and pyrimidines. Most Hemolymph amino acids had two elevations during the feeding period of the fourth instar and prepupa stage. Trehalose was the major blood sugar before day 8 of the fifth instar, whereas glucose became the major blood sugar after spinning. C16:0, C18:0 and its unsaturated forms were dominant fatty acids in Hemolymph. The developmental changes of Hemolymph metabonome were associated with dietary nutrient intakes, biosyntheses of cell membrane, pigments, proteins, and energy metabolism. These findings offered essential biochemistry information in terms of the dynamic metabolic changes during silkworm development.
Kazuhisa Sekimizu - One of the best experts on this subject based on the ideXlab platform.
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identification of a serratia marcescens virulence factor that promotes Hemolymph bleeding in the silkworm bombyx mori
Journal of Invertebrate Pathology, 2014Co-Authors: Kenichi Ishii, Tatsuo Adachi, Takashi Hara, Hiroshi Hamamoto, Kazuhisa SekimizuAbstract:Injection of culture supernatant of Serratia marcescens, a Gram-negative bacterium pathogenic to a wide range of host animals including insects and mammals, into the Hemolymph of silkworm (Bombyx mori) larvae led to continuous flow of the Hemolymph (blood of insects) from the injection site. The amount of Hemolymph lost within 60 min reached 15-20% of the total larval weight. Using a bioassay with live silkworms, we purified Serralysin, a metalloprotease that requires divalent cations for its activity, as the factor responsible for the promotion of Hemolymph bleeding from the culture supernatant of S. marcescens. Recombinant protein also induced Hemolymph bleeding in silkworms. Moreover, the culture supernatant of an S. marcescens disruption mutant of the ser gene showed attenuated ability to promote Hemolymph bleeding. In addition, this bleeding-promoting activity of the S. marcescens culture supernatant was attenuated by disruption of the wecA gene, which is involved in the biosynthesis of the lipopolysaccharide O-antigen. These findings suggest that Serralysin metalloprotease contributes to the pathogenesis of S. marcescens by inhibiting wound healing, which leads to a massive loss of Hemolymph from silkworm larvae.
Won Jong Rhee - One of the best experts on this subject based on the ideXlab platform.
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Enhanced production of recombinant protein inEscherichia coli using silkworm Hemolymph
Biotechnology and Bioprocess Engineering, 2005Co-Authors: Ji Eun Kim, Eun Jeong Kim, Won Jong Rhee, Tai Hyun ParkAbstract:The effect of silkworm Hemolymph on the expression of recombinant protein inEscherichia coli was investigated. The addition of silkworm Hemolymph to the culture medium increased the production of recombinant β-galactosidase inE. coli. The production was dependent on the concentration of the added silkworm Hemolymph, which increased 2-, 5-, and 8-fold in media supplemented with 1,3, and 5% silkworm Hemolymph, respectively. To identify the effective component, the silkworm Hemolymph was fractionated by gel filtration column chromatography. A fraction, with a molecular weight of about 30 K was identified as the effective component.
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Inhibition of human cell apoptosis by silkworm Hemolymph.
Biotechnology progress, 2002Co-Authors: Shin Sik Choi, Won Jong Rhee, Tai Hyun ParkAbstract:Many studies on preventing apoptosis have been carried out from the viewpoint of anti-apoptotic cloned-gene expressions inside cells, whereas in this study, we investigated the inhibition of apoptosis by the addition of silkworm Hemolymph, a natural compound, from outside of the cells. In a previous study, we reported the inhibition effect of silkworm Hemolymph on the baculovirus-induced insect cell apoptosis. Using the vaccinia virus-HeLa cell system as a model system in this study, we found that silkworm Hemolymph, the insect serum, inhibits apoptosis not only in the insect cell system but also in the human cell system. The vaccinia virus-induced HeLa cell apoptosis was analyzed using DNA electrophoresis, TUNEL, and flow cytometry, and the resulting data confirmed that silkworm Hemolymph inhibits human cell apoptosis. The inhibition of apoptosis due to silkworm Hemolymph was not caused by an inhibition of virus binding and internalization steps, nor did silkworm Hemolymph interfere with the virus production. The inhibition of apoptosis by silkworm Hemolymph decreased the cell detachment from an adhering surface. With these characteristics, silkworm Hemolymph can be effectively used to minimize cell death in commercial animal cell culture.
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Silkworm Hemolymph inhibits baculovirus-induced insect cell apoptosis.
Biochemical and biophysical research communications, 2000Co-Authors: Won Jong Rhee, Tai Hyun ParkAbstract:The effect of silkworm Hemolymph on baculovirus-induced insect cell apoptosis was investigated. The addition of silkworm Hemolymph into the culture medium either before or during the baculovirus infection increased the host cell longevity; however, its addition after the infection was less effective. This can be explained by the higher transfer rate of silkworm Hemolymph which is caused by endocytosis during the virus internalization step. The delayed cell death due to silkworm Hemolymph was not caused by an inhibition of the virus attachment and internalization steps. The apoptosis was analyzed using DNA fragmentation and TUNEL assays, and the resulting data confirm that silkworm Hemolymph inhibits baculovirus-induced insect cell apoptosis.