• The Korean Journal of Mycology
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• v.15 no.3
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• pp.149-157
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• 1987

This study was undertaken to investigate the differentiation, from spore germination to hyphae growth and phialide formation, of Aspergillus niger through the method of synchronous and submerged culture. Through continuous experiments by shake culture with potassium acetate medium, we observed the formation of spores at appropriate concentration and pH. Potassium acetate medium was set pH 5.5, 6.0, 6.5 and 7.0 on each scale, and control, 20 mM, and 40 mM, 80 mM and 160 mM concentrations on the other scale. Aspergillus niger was cultured in the defined media at $28^{\circ}C$, and mycelial dry weight, changes of pH and the onset of sporulation were checked. The mycelial dry weight, increased in potassium acetate medium, and pH increased during mycelial growth and gradually decreased after the spore formation. When pH increased excessively in Potassium acetate medium with pH 7.0, the mycelia could not adapt and mycelial dry weight decreased gradually. At pH 5.5, the onset of sporulation was done within one day at 20 mM it took, at 80 mM three days and at 160 mM concentration. in two days, at 40 mM one to four days were taken, 80 mM concentration respectively. At pH 6.5, the onset of sporulation was done in three days and four days at 80 mM concentrations respectively. Spore formation was not shown at pH 7.0. In controlled medium with all levels of pH, spore formation was not shown.

• Korean Journal of Food Science and Technology
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• v.22 no.2
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• pp.177-182
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• 1990

The changes in the partition coefficient of model proteins (lysozyme, myoglobin, conalbumin, bovine serum albumin) in an aqueous two·phase system formed by polyethylene glycol and dextran were examined in order to improve the capacity of counter current distribution (CCD) for the protein fractionation and concentration . The protein distribution pattern in CCD with 30 tubes varied with the pH (4.5, 5.5, 6.5, 9.0, 12.0) and KCl concentration (0mM, 50mM, 250mM, 500mM) of the system. From the mixture of model proteins, pure myoglobin was appeared at the upperphase of 14th tube having 50mM of KCl at pH 5.5 and the upper-phase of 13th tube having 250mM of KCl at pH 6.5. Similarly pure BSA was obtained at the 14th tube having KCl 250mM with pH 4.5, pure lysozyme at the 19th tube having 500mM of KCl at pH 4.5 and the upper-phase of 16th tube 50mM of KCl at pH 5.5.

• Korean Journal of Environmental Biology
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• v.18 no.2
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• pp.269-277
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• 2000

When Persicaria thunbergii and Rumex crispus were treated with Cd($NO_3$)$_2$ and Pb($NO_3$)$_2$ of 5 or 10 mM for 5 days, the amount of bioaccumulation of $Pb^{2+}$ in the leaf of P. thunbergii was 2.87-8.08$\mu\textrm{g}$/g and that of $Cd^{2+}$ was 0.82-2.79$\mu\textrm{g}$/g. In the case of P. thunbergii, the concentration of $Pb^{2+}$ in the leaf was higher than that of $Cd^{2+}$. On the other hand, in R. crispus, the concentration of $Cd^{2+}$ and $Pb^{2+}$ were similar as follows ; 1.49$\mu\textrm{g}$/g in $Cd^{2+}$ 5mM, 2.90$\mu\textrm{g}$/g in Cd2+ 10mM, 1.83$\mu\textrm{g}$/g in $Pb^{2+}$ 5mM and 2.73$\mu\textrm{g}$/g in $Pb^{2+}$ 10mM. The remaining rate of heavy metals and the variation of pH in the cultured soil decreased as compared with control (100 % and pH 6.48) after 5 days as follows; to 77.l% and pH 6.39 in $Cd^{2+}$ 5mM, 90.2% and pH 5.79 in $Cd^{2+}$ 10 mM, 81.1% and pH 6.00 in $Pb^{2+}$ 5mM, and 85.7% and pH 5.80 in $Pb^{2+}$ 10 mM. The result of size exclusion chromatography, several phytochelatins were seperated from the extract of the leaf of both plants treated with heavy metals. The molecular mass of these phytochelatins were estimated as follows; in the case of P. thunbergii, about 4,300-8,600 da by $Cd^{2+}$ and about 3,200-9,700 da by $Pb^{2+}$, and in R. crispus, about 4,300 da by $Cd^{2+}$ and about 3,200-7,500 da by $Pb^{2+}$. In addition, $A_{254}$ of these phytochelatins were higher than $A_{280}$. [Phytochelatin, Persicaria thunbergii, Rumex crispus]

• Applied Biological Chemistry
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• v.33 no.4
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• pp.325-329
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• 1990

This study was undertaken to determine thermodynamic characteristics of B. subtilis p-4 and B. licheniformis p-5 proteases isolated from fermented anchovy paste. $K_m$ values of two proteases for casein as a substrate were 0.38mM in p-4 protease and 0.18mM in p-5 protease, respectively. Denaturation constants($K_D$) of p-4 and p-5 proteases were $12.2{\times}10^{-5}/sec\;and\;19.0{\times}10^{-5}/sec\;at\;40^{\circ}C,\;and\;35.7{\times}10^{-5}/sec\;and\;46.3{\times}10^{-5}/sec\;at\;50^{\circ}C$, respectively. Activation energies($E_a$) of p-4 and p-S pmteases were 19.6 Kcal/mole and 15.2kcal/mole, respectively. Free energy of activation(${\Delta}G^*$), activation enthalpy(${\Delta}H^*$) and activation entropy(${\Delta}S^*$) at $40^{\circ}C$ were 23.21Kcal/mole, 18.98Kcal/mole and -13.50 eu, respectively for p-4 protease and 22.93Kcal/mo1e, 14.58Kcal/mole and -26.68 eu, respectively for p-5 protease. The major amino acids in p-4 protease(151 residues of amino acid) were Gly, Glu, Pro, Asp, Ser, Ala, Lys and Leu, while those in p-5 protease(247 residues of amino acid) were Gly, Glu, Asp, Ala and Leu. It may be concluded that heat denaturation of two proteases showed liner regression curve and p-5 protease was more sensitive to heat than p-4 protease.

• BMB Reports
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• v.32 no.5
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• pp.492-496
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• 1999

We have investigated the biochemical properties of the herpes simplex virus type 1 (HSV-1) DNA polymerase without the UL42 protein (Pol), purified from insect cells infected with a recombinant baculovirus containing the UL30 gene. BSA and DTT have inhibitory effects on dAMP incorporation. Pol showed a greater turnover rate of steady-state single nucleotide incorporation at 12 mM $MgCl_2$ than at 2 mM $MgCl_2$. However, it showed a greater processivity of DNA synthesis at lower $MgCl_2$ concentration (1 mM, 2 mM) than at a higher $MgCl_2$ concentration (12.5 mM). These results are consistent with a slow DNA dissociation at lower $MgCl_2$ concentrations. Pol does not incorporate a correct nucleotide into the primer with an incorrect nucleotide at the end; instead, it preferentially excises the incorrect nucleotide at the 3' end of the primer. Pol has DNA polymerase activity at pHs 6.5 and 7.5 but little at pHs 5.5, 8.5, and 9.5. It has exonuclease activity at pHs 6.5, 7.5, and 8.5 but little at pHs 4.5, 5.5, and 9.5. The finding that Pol has exonuclease activity but not DNA polymerase at pH 8.5 suggests that DNA binds to Pol, but deoxynucleotide binding or incorporation does not occur at pH 8.5.

• Korean Journal of Microbiology
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• v.30 no.4
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• pp.305-309
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• 1992

Cytosine deaminase (EC 3.5.4.1) from BaciNus stc~urorhermophilus was partially purified 7.2-fold with an overall yield of 52.7%. The partially purified enzyme deiiminated cytosine only.but not 5-methylcytosine and 5-fluorocytosine. The apparent Michaclis constant. Km valuefor cytosine was 5.9 mM. The enzyme was relatively stable in the range of pH 4.0 to 7.0.furthermore extremely thermo-stable : more than 75'X) of the activity was remained afterheating at 80$^{\circ}$C for I0 min at pH 6.5. The enzyme had a pH optimum at around pH7.0 to 7.5. and temperature optimum at 35 to 31$^{\circ}$C. And the activation energ (En value)determined from an Arrhenius plot was 26 Kcal/mol. The enzyme activity was stronglyinhibited by heavy metal ions such as Cd", Hg". Cut' at 1 mM, anJ by o-phenanthroline,and p-chloromcrcuribcnzoate at I mM. But the enrymc activity was activatetl increased byGMP, and CMP at 1 mM.ased by GMP, and CMP at 1 mM.

• Journal of Acupuncture Research
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• v.21 no.3
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• pp.107-119
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• 2004

Objective : The purpose of this study was to investigate the effect of Bee Venom and melittin on the lipopolysaccharide(LPS) and sodium nitroprusside(SNP)-induced expressions of Cell viability, nitric oxide(NO), inducible nitric oxide synthase(iNOS), extra-signal response kinase(ERK), jun N-terminal Kinase(JNK) and p38 kinase(p38)- mitogen activated protein kinase(MAPK) Family- in RAW 264.7 cells, a murine macrophage cell line. Methods : The expressions of cell viability by MTT assay, NO by Nitrite assay and iNOS, ERK, JNK and p38 were determined by Western blotting. Results : 1. Compared with the control group, 0.5, 1, $5{\mu}g/m{\ell}$ bee venom and 5, $10{\mu}g/m{\ell}$ melittin increased cell viability of RAW 264.7 induced by LPS and SNP significantly respectively. 2. Compared with the control group, 0.5, 1, $5{\mu}g/m{\ell}$ bee venom and 5, $10{\mu}g/m{\ell}$ melittin inhibited expression of NO induced by LPS and SNP significantly respectively. 3. Compared with the control group, 1, $5{\mu}g/m{\ell}$ bee venom and 5, $10{\mu}g/m{\ell}$ melittin inhibited expression of iNOS induced by LPS significantly and 0.5, 1, $5{\mu}g/m{\ell}$ bee venom and 5, $10{\mu}g/m{\ell}$ melittin inhibited expression of iNOS induced by SNP significantly. 4. Compared with the control group, the expression of ERK induced by LPS and SNP decreased significantly in the treatment groups of $5{\mu}g/m{\ell}$ bee venom and 5, $10{\mu}g/m{\ell}$ melittin, which of p-ERK by LPS also did in 1, $5{\mu}g/m{\ell}$ bee venom and 5, $10{\mu}g/m{\ell}$ melittin, but which of p-ERK by SNP did not decrease. 5. Compared with the control group, the. expression of JNK induced by LPS and SNP decreased significantly in the treatment groups of 5, $10{\mu}g/m{\ell}$ melittin, which of p-JNK by LPS in 5, $10{\mu}g/m{\ell}$ melittin and by SNP in $1{\mu}g/m{\ell}$ bee venom and $10{\mu}g/m{\ell}$ melittin decreased significantly. 6. Compared with the control group, the expression of p38 induced by LPS did not have significant difference, which induced by SNP decreased significantly in the treatment groups of 1, $5{\mu}g/m{\ell}$ bee venom and 5, $10{\mu}g/m{\ell}$ melittin. p-p38 induced by LPS decreased significantly in the treatment group of $10{\mu}g/m{\ell}$ of melittin, which induced by SNP also decreased significantly in 0.5, 1, $5{\mu}g/m{\ell}$ bee venom and 5, $10{\mu}g/m{\ell}$ melittin.

• KSBB Journal
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• v.5 no.1
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• pp.9-17
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• 1990

The growth and fermentation profiles of Clostridium acetobutylicum KCTC 1037 were examined in batch and continuous modes with pH variation and phosphate limitation. Clostridium acetobutylicum KCTC 10 37 grew better at pH 4.5 than at pH 5.5 or 6.5. Acetate and butyrate were produced at pH 5.5, whereas culture at pH 4.5 produced acetone and butanol. Solvent production was increased by the phosphate limitation in a batch culture, but in a phosphate-limited continuous culture for 400 hours steady-state solventogenesis was not observed. The induction and maintenance of solventogenesis presumably require not only acidic condition or phosphate limitation but also favourable bioenergetic condition.

• Journal of Acupuncture Research
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• v.22 no.3
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• pp.155-167
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• 2005

Objectives : The purpose of this study was to investigate the anti-inflammatory effect of Cobrotoxin on binding affinity of cobrotoxin with P50, $IKK{\alpa}$ and $IKK{\beta}$, activities of NF-${\kappa}B$, Cell viability of astrocyte, expressions of protein molecules of NF-${\kappa}B$ such as P50, P-$1{kappa}B$, $1{\kappa}B$ and iflammation related genes such as Cox-2, iNOS, cPLA2 in the SNP or LPS induced Inflammatory pathway of Rats' astrocytes. Methods : In this study, The expression of cytosolic phospholipase A2, Nitric oxcide, Cyclooxygenase-2 and inducible nitrogen oxide synthase was determined by western blotting with corresponding antibodies, and the generation of NF-${\kappa}B$ was assayed by EMSA method in astrocytes of rats. The Cell viability of astrocytes was determined by MTT assay, and Binding affinity of Cobrotoxin with P50, $IKK{\alpha}$ and $IKK{\beta}$ was assayed by Surface plasmon resonance analysis, and NF-${\kappa}B$ dependent luciferase activity was determined by luciferase analysis, and Uptake of cobrotoxin in astrocytes was identified by Confocal laser scanning microscope Results : 1. Compared with control, LPS-induced NF-${\kappa}B$ DNA binding activity was decreased significantly by 0.1, $0.5{\mu}g/m{\ell}$ of Cobrotoxin in Astrocyte. 2. Compared with control, LPS-induced NF-kB dependent luciferase expression was decreased significantly by 0.1, 0.5 and $1{\mu}g/m{\ell}$ of Cobrotoxin in Astrocyte. 3. Compared with control, SNP induced P50, $I{\kappa}B$ expressions in astrocyte were decreased significantly by 0.1, 0.5 and $1{\mu}g/m{\ell}$ of Cobrotoxin and P-$1{\kappa}B$ expression was decreased significantly by 0.5 and $1{\mu}g/m{\ell}$ of Cobrotoxin. 4. Compared with control, LPS induced P50, $1{\kappa}B$ expressions in astrocyte were decreased significantly by 0.5 and $1{\mu}g/m{\ell}$ of Cobrotoxin. 5. Compared with control, SNP induced Cox-2, iNOS, CPLA2 expressions in astrocyte were decreased significantly by $1{\mu}g/m{\ell}$ of Cobrotoxin. 6. Compared with control, LPS induced Cox-2, cPLA2 expressions in astrocyte were decreased significantly by 0.1, 0.5, $1{\mu}g/m{\ell}$ of Cobrotoxin and iNOS expression was decreased significantly by 0.5, $1{\mu}g/m{\ell}$ of Cobrotoxin. 7. Compared with $0.5{\mu}g/m{\ell}$ of Cobrotoxin, SNP-induced NF-${\kappa}B$ DNA bindins activity in astrocyte was increased significantly by Cobrotoxin $0.5{\mu}g/m{\ell}$ with DTT 1mM and Cobrotoxin $0.5{\mu}g/m{\ell}$ with DTT 5mM. 8. Compared with $0.5{\mu}g/m{\ell}$ of Cobrotoxin, LPS-induced NF-${\kappa}B$ DNA binding activity in astrocyte was increased significantly by Cobrotoxin $0.5{\mu}g/m{\ell}$ with DTT 1mM, Cobrotoxin $0.5{\mu}g/m{\ell}$ with DTT 5mM, Cobrotoxin $0.5{\mu}g/m{\ell}$with GSH 1mM and Cobrotoxin $0.5{\mu}g/m{\ell}$ with GSH 5mM 9. Compared with $0.1{\mu}g/m{\ell}$ of cobrotoxin, SNP induced P50 expressions in astrocyte were increased significantly by Cobrotoxin $0.5{\mu}g/m{\ell}$ with DTT 1mM, Cobrotoxin $0.5{\mu}g/m{\ell}$ with DTT 5mM Cobrotoxin $0.5{\mu}g/m{\ell}$ with GSH 1mM and Cobrotoxin $0.5{\mu}g/m{\ell}$ with GSH 5mM. 10. The uptake of the labeled cobrotoxin into the cells was shown under a confocal laser scanning microscope. cobrotoxin was uptaken into the membrane and nucleus of astrocytes. Conclusions : In summary, the present results demonstrate that cobrotoxin directly binds to sulfhydryl group of p50 and IKKS resulting In the reduction of translocation of p50 and IkB release, thereby inhibits activation of NF-${\kappa}B$, and suggest that pico to nanomolar range of cobrotoxin could inhibit the expression of genes in the NF-${\kappa}B$ signal pathway.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.1
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• pp.41-49
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• 2003

Methane emission was measured in a rice paddy under different water management and organic amendments. Methane emission from planted chambers and unplanted chambers was monitored to evaluate the rice-mediated methane emission. In flooding methane emission from planted chambers with NPK, NPK(+P), was $0.174g\;CH_4\;m^{-2}\;d^{-1}$ while that from unplanted chambers with NPK, NPK(-P), was $0.046g\;CH_4\;m^{-2}\;d^{-1}$ Methane emission from planted chambers with rice straw compost amendment, RSC(+P), was $0.214g\;CH_4\;m^{-2}\;d^{-1}$, while that from unplanted chambers with rice straw compost amendment, RSC(-P), was $0.076g\;CH_4\;m^{-2}\;d^{-1}$. Methane emission from planted chambers with rice straw amendment in Fehruary, RS2(+P), was $0.328g\;CH_4\;m^{-2}\;d^{-1}$, while that from unplanted chambers with rice straw amendment in February, RS2(-P), was $0.1g\;CH_4\;m^{-2}\;d^{-1}$. Methane emission from planted chambers with rice straw amendment in May, RS5(+P), was $0.414g\;CH_4\;m^{-2}\;d^{-1}$, while that from unplanted chamhers with rice straw amendment in May, RS5(-P), was $0.187g\;CH_4\;m^{-2}\;d^{-1}$. In intermittent irrigation methane emission from NPK(+P) was $0.115g\;CH_4\;m^{-2}\;d^{-1}$, while that from NPK(-P) was $0.041g\;CH_4\;m^{-2}\;d^{-1}$. Methane emission from RSC(+P) was $0.137g\;CH_4\;m^{-2}\;d^{-1}$, while that from RSC(-P) was $0.06g\;CH_4\;m^{-2}\;d^{-1}$. Methane emission from RS2(+P) was $0.204g\;CH_4\;m^{-2}\;d^{-1}$, while that from RS2(-P) was $0.09g\;CH_4\;m^{-2}\;d^{-1}$. Methane emission from RS5(+P) was $0.273g\;CH_4\;m^{-2}\;d^{-1}$, while that from RS5(-P) was $0.13g\;CH_4\;m^{-2}\;d^{-1}$. Methane transport via rice plant under flooding for NPK plot, RSC plot, RS2 plot and RS5 plot was 73.6%, 64.5%, 69.5% and 54.8%, respectively, and mean was 65.6%. Methane transport via rice plants under intermittent irrigation for NPK plot, RSC plot, RS2 plot and RS5 plot was 64.3%, 59.2%, 55.9% and 52.4%, respectively, and mean was 58.0%.