• Microbiology and Biotechnology Letters
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• v.17 no.4
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• pp.273-276
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• 1989

The isolate SPO 3, an oligosporogenous and crystalliferous mutant, which was isolated from Bacillus thuringiensig subsp, israelensis by heat treatment at 42$^{\circ}C$ for 24 hit. The $\delta$-endotoxin of the mutant had a relatively low hemolytic activity on human red blood cells; the $\delta$-endotoxin of the mutant had 25 times less hemolytic activity compared to that of wild strain. The loss of 28 KDa hemolytic protein subunit in $\delta$-endotoxin of the mutant was confirmed by means of double immunodiffusiori, immunoelectrophoresis, and SDS-PAGE.

• Journal of Preventive Medicine and Public Health
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• v.7 no.1
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• pp.115-121
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• 1974

In order to evaluate the health hazard due to exposure to organophosphorus insecticides, we measured the blood cholinesterase activity ana urinary para-nitrophenol among 56 exposed subjects. They are orchard workers, rice plant workers and smithion factory workers. The clinical symptoms were also checked by physicians. We also measured the blood cholinesterase activity and urinary para-nitrophenol excretion of 20 urban people and 15 rural people who had never been exposed to organophosphorus insecticides in order to compare them according to age, sex and geographical differences. And these results were also compared with those of exposed groups. The results obtained were as follows. 1. The normal plasma cholinesterase activity and cell cholinestrase activity were $0.861{\pm}0.148\;{\Delta}pH/hr$ and $0.822{\pm}0.154\;{\Delta}pH/hr$. And normal para-nitrophenol in urine was $1.21{\pm}0.52mg/liter$. 2. No significant difference was existed in blood cholinesterase activities and urinary para-nitrophenol excre tion according to sex, age and geographical difference. 3. The plasma cholinesterase activity and cell cholinesterase activity of orchard workers, rice plant workers and smithion factory workers were $0.682{\pm}0.189\;{\Delta}pH/hr,\;0.775{\pm}0.160\;{\Delta}pH/hr,\;0.754{\pm}0.123\;{\Delta}pH/hr,\;and\;0.691{\pm}0.082\;{\Delta}pH/hr,\;0.756{\pm}0.117\;{\Delta}pH/hr,\;0.739{\pm}0.117\;{\Delta}pH/hr$. And significant decreses in blood cholinesterase activities were existed among orchard workers and smithion factory workers compared with control group. 4, The urinary para-nitrophenol excretions of orchard workers, rice plant workers and smithion factory workers were $1.33{\pm}0.66mg/liter,\;1.19{\pm}0.88mg/liter\;and\;1.37{\pm}0.67mg/liter$ and there were no significant difference between exposed groups and control group. 5. The clinical symptoms complained during and after organophosphorus insecticides exposure were frequently ranked by headache (67.7%) and vertigo (64.5%) and muscular ataxia and weakness (51.6%).

• YAKHAK HOEJI
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• v.19 no.1
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• pp.21-29
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• 1975

The activity of $\delta$-aminolevlinic acid dehydratase (ALAD) in red cell of rabbit inhibited by addition of $Pb(Ac)_{2}$(50mg/kg) to rabbit caused to diminish completely the ALAD activity in blood within shr. Pretreatment of ascorbic acid and methionine decreased the increment of $\delta$-aminolevulinic acid output in urine by lead poisoning.

• Reproductive and Developmental Biology
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• v.34 no.1
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• pp.47-53
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• 2010

Glycoprotein hormones have a common $\alpha$-subunit that is involved in the signaling pathway together with G protein, adenylcyclase and cAMP induction; however, it is an unclear how this common structure is related to hormonal action. To determine the biological functions of the COOH-terminal amino acids in the $\alpha$-subunit of these glycoprotein hormones, a tethered-molecule was constructed by fusing the $NH_2$-terminus of the $\alpha$-subunit to the COOH-terminus of the $\beta$-subunit of equine chorionic gonadotropin (eCG). The following deletion mutants were created by PCR; Ile was inserted at position 96 to form ${\Delta}96$, Lys was substituted at position 95 to form ${\Delta}95$, His was inserted at position 93 to form ${\Delta}93$ and Tyr was substituted at position 87 to form ${\Delta}87$. Each mutant was transfected into CHO-K1 cells. Tethered-wt eCG, and ${\Delta}96$, ${\Delta}95$, and ${\Delta}93$ mutants were efficiently secreted into the medium but the ${\Delta}87$ mutant was not secreted. Interestingly, the RT-PCR, real-time PCR, and northern blot analyses confirmed that the RNA was transcribed in the ${\Delta}87$ mutant. However, the ${\Delta}87$ mutant protein was not detected in the medium or the intracellular fraction of the cell lysates. The LH- and FSH-like activities of the recombinant proteins were assayed in terms of cAMP production using rat LH/CG and rat FSH receptors. The metabolic clearance rate (MCR) was determined by injecting rec-eCG (2 IU) into the tail vein. The ${\Delta}95$ and ${\Delta}93$ mutants were completely inactive in both the LH- and FSH-like activity assays. The ${\Delta}96$ mutant showed slight activity in the LH-like activity assay. In comparison to the wild type, the activity of the ${\Delta}96$ mutant in the FSH-like activity assay was the highest among all the mutants. The MCR assay in which rec-eCG was injected showed a peak at 10 min in all the treatment groups, which disappeared 4 h after injection. These results imply a direct interaction between the receptor and the COOH-terminal region of the a-subunit. The data also reveal a significant difference in the mechanism by which the eCG hormone interacts with the rLH and rFSH receptors. The COOH-terminal region of the $\alpha$-subunit is very important for the secretion and functioning of this hormone.

• Applied Biological Chemistry
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• v.38 no.4
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• pp.320-324
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• 1995

Solubilization of microsomal ${\Delta}^{5}-3{\beta}$-hydroxy steroid acyl transfearse(${\Delta}^{5}-3{\beta}$-OH-SAT) of rat brain and its reconstitution into liposomes were investigated. Among the detergents utilized for the solubilization, deoxycholic acid was superior to Tween 80 or Triton X-100 for the reconstituted activity of ${\Delta}^{5}-3{\beta}$-OH-SAT. The enzyme activity was shown to be affected by the nature of phospholipids used for the preparation of the liposome. Phosphatidylcholines from egg yolk and soybean showed the highest activity of ${\Delta}^{5}-3{\beta}$-OH-SAT and phosphatidylethanolamine came next. However phosphatidylserine and phosphatidic acid showed a lower activity than those obtained before the reconstitution. This study suggests that the presence of quaternary ammonium salt or amine group in the phospholipids stimulates the activity of ${\Delta}^{5}-3{\beta}$-OH-SAT. However the presence of a carboxylic group or the absence of the amine group may have an inhibitory effect on the ${\Delta}^{5}-3{\beta}$-OH SAT.

• Journal of Society of Preventive Korean Medicine
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• v.4 no.2
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• pp.214-234
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• 2000

This study was carried to identify whether acupuncture of several acupuncture points can affect the brain and to observe which aspects appear in EEG mapping, using electroencephalography. Those results are as follows ; 1. The pattern of resting computerized EEG map in intact human is appered normal 2. Each Acupuncture in Kwan Weon or Jog Sam Ri meridian points bring about the increase in $\theta,\;\alpha-wave$ activity and at various area of the cerebrium and the decrease in $\delta,\;\beta-wave$ activity. It strands to reason that brain function is elevated On the other hand , synchronous acupuncture bring about the decrease of brain function in view of the decrease of $\delta,\;\theta-wave$ activity at frontal area, and the unstable brain state in view of the increase of $\beta-wave$ activity. 3. Acupuncture in Hyeon Jong meridian point bring about the increase of $\delta,\;\theta-wave$ activity at frontal area and $\beta-wave$ activity at temporal area. From these we deduce that brain function is declined and brain is unstable. Synchronous acupuncture with other meridian points reversly showed that brain function is elevated. 4. Synchronous acupuncture in Kwan Weon , Jog Sam Ri, Hyeon Jong bring about the decrease of the brain function and the unstable brain state, showing the pattern of increased $\delta,\;\theta-wave$ activity at frontal, parietal area, and increased $\beta-wave$ activity at temporal area.

• Journal of Life Science
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• v.24 no.10
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• pp.1046-1054
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• 2014

Beta-1,3-glucanase is widely used in various biotechnological and industrial processes, with over-production required to enable versatile utilization. We examined the overexpression of ${\beta}$-1,3-glucanase (EXGA) from Aspergillus oryzae using ${\delta}$-sequence-mediated integration. We constructed $pRS{\delta}$-exgA and $pRS{\delta}K$-exgA plasmids for integration of the EXGA gene into various chromosomes of Saccharomyces cerevisiae. These plasmids contain the ADH1 promoter for constitutive expression, a signal sequence (exoinulinase signal sequence [INU1 s.s]) for secretory production, and a ${\delta}$-sequence for integration of ${\beta}$-1,3-glucanase. The $pRS{\delta}$-exgA plasmid was transformed into the S. cerevisiae $BY4742{\Delta}exg1$ strain, and ${\beta}$-1.3-glucanase was stably overexpressed and secreted. Another plasmid, $pRS{\delta}K$-exgA, was introduced into the S. cerevisiae $BY4742{\Delta}exg1$ (YKY082) strain, and overexpression of ${\beta}$-1,3-glucanase was examined by inducible integration under geneticin selection. The activity of ${\beta}$-1,3-glucanase increased in accordance with a rise in the geneticin concentration, with 0.8 mg/ml of geneticin suitable for overexpression of ${\beta}$-1,3-glucanase. Subsequently, $pRS{\delta}K$-exgA was repeatedly transformed for sequential ${\delta}$-integration. The activity of ${\beta}$-1,3-glucanase reached about 0.063 unit/ml/$OD_{600}$, 0.095 unit/ml/$OD_{600}$, 0.131 unit/ml/$OD_{600}$ and 0.165 unit/ml/$OD_{600}$ by the first, second, third, and fourth round of integration, respectively. According to the increase in the activity of ${\beta}$-1,3-glucanase by sequential ${\delta}$-integration, the copy number (integration rate) of the EXGA gene also increased in various chromosomes. These results suggest that recombinant ${\beta}$-1,3-glucanase activity can be sequentially increased by repeated ${\delta}$-sequence integration.

• BMB Reports
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• v.44 no.6
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• pp.375-380
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• 2011

Bacillus licheniformis SK-1 naturally produces chitinase 72 (CHI72) with two truncation derivatives at the C-terminus, one with deletion of the chitin binding domain (ChBD), and the other with deletions of both fibronectin type III domain (FnIIID) and ChBD. We constructed deletions mutants of CHI72 with deletion of ChBD (CHI72${\Delta}$ChBD) and deletions of both FnIIID and ChBD (CHI72${\Delta}$FnIIID${\Delta}$ChBD), and studied their activity on soluble, amorphous and crystalline substrates. Interestingly, when equivalent amount of specific activity of each enzyme on soluble substrate was used, the product yield from CHI72-${\Delta}$ChBD and CHI72${\Delta}$FnIIID${\Delta}$ChBD on colloidal chitin was 2.5 and 1.6 fold higher than CHI72, respectively. In contrast, the product yield from CHI72${\Delta}$ChBD and CHI72${\Delta}$FnIIID-${\Delta}$ChBD on ${\beta}$-chitin reduced to 0.7 and 0.5 fold of CHI72, respectively. These results suggest that CHI72 can modulate its substrate specificities through truncations of the functional domains at the C-terminus, producing a mixture of enzymes with elevated efficiency of hydrolysis.

• Journal of Microbiology and Biotechnology
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• v.15 no.5
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• pp.1080-1086
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• 2005

Membranes prepared from Vibrio natriegens oxidized both NADH and deamino-NADH as substrates. The maximum activity of the membrane-bound NADH oxidase was obtained at about pH 8.5 in the presence of 0.2 M NaCl, whereas that of the NADH:ubiquinone oxidoreductase was obtained at about pH 7.5 in the presence of 0.2 M NaCl. Electron transfer from NADH or deamino-NADH to ubiquinone-l or oxygen generated a considerable membrane potential (${\Delta}{\psi}$), which occurred even in the presence of $20{\mu}M$ carbonylcyanide m-chlorophenylhydrazone (CCCP). However, the ${\Delta}{\psi}$ was completely collapsed by the combined addition of $10{\mu}M$ CCCP and $20{\mu}M$ monensin. On the other hand, the activity of the NADH oxidase and the ${\Delta}{\psi}$ generated by the NADH oxidase system were inhibited by about $90\%$ with $10{\mu}M$ HQNO, whereas the activity of the NADH:ubiquinone oxidoreductase and the ${\Delta}{\psi}$ generated at the NADH:ubiquinone oxidoreductase segment were inhibited by about $60\%$. Interestingly, the activity of the NADH:ubiquinone oxidoreductase and the ${\Delta}{\psi}$ generated at the NADH:ubiquinone oxidoreductase segment were resistant to the respiratory chain inhibitors such as rotenone, capsaicin, and $AgNO_3$, and the activity of the NADH oxidase and the ${\Delta}{\psi}$ generated by the NADH oxidase system were very sensitive only to $AgNO_3$. It was concluded, therefore, that V. natriegens cells possess a $AgNO_3$-resistant respiratory $Na^+$ pump that is different from the $AgNO_3$-sensitive respiratory $Na^+$ pump of a marine bacterium, Vibrio alginolyticus.

• Journal of the Korean Society of Safety
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• v.14 no.4
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• pp.100-107
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• 1999

The purpose of the study is to investigate the effect of H$_2$ pressure on partial discharge (PD) activity and aging rate in turbine generator winding insulations. A series of field tests and laboratory tests were peformed to investigate the effect of $H_2$ pressure on PD activity. Field tests were conducted at two unit turbine generators in two conditions, in $H_2$ pressure and in air atmosphere. Obtained results are as follows ; 1) ${\Delta}tan{\delta}$ and maximum partial discharge are reduced with increase of $H_2$ pressure and partial discharge inception voltage. 2) The reduction ratio of ${\Delta}tan{\delta}$ due to $H_2$ pressure is higher than one of PD magnitude. 3) Partial discharge pulses suffer from attenuation and distortion when transmitted along windings, because of the complex L-C network between windings. From the result, partial discharge pulses are subjected to resonance phenomena in a generator winding.