• The Korean Journal of Mycology
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• v.19 no.3
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• pp.220-225
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• 1991

Activities of the $F_1-ATPase$ purified from Lentinus edodes were stimulated by $Fe^{3+},\;Fe^{2+},\;Cd^{2+},\;Mg^{2+},\;K^{+}\;and\;Co^{2+}$ but were inhibited by $Zn^{2+},\;Ca^{2+},\;Cu^{2+}\;and\;Ni{2+}$ ion. The enzyme activities were increased 130, 65, 65, 68, 105% and 23% by the 5mM $Fe^{3+}$, 10 mM$Fe^{2+}$, 1mM $Cd^{2+}$, 5mM $Mg^{2+}$, 5mM $K^{+}$ and 5mM$Co^{2+}$ ion addition, respectively, as compared with those not added. The enzyme activities were decreased 18, 19, 27 and 30% by 10 mM $Zn^{2+}$, 10mM $Ca^{2+}$, 0.5 mM $Cu^{2+}$ and 10 mM $Ni^{2+}$ ion, respectively. Anion effects of 10 mM ${Co_3}^{2-}$, 20 mM,$CN^{-}$ 20 mM$CH_3COO^{-}$ and 20 mM ${NO_3}^{-}$ ion were inhibited to the enzyme activities of 98, 95, 70 and 50%, respectively. As increasing of ${SO_4}^{2-}$ ion concentration, the enzyme activity was stimulated and 20 mM ${SO_4}^{2-}$ ion was shown increased of 21%.

• The Korean Journal of Physiology
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• v.9 no.1
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• pp.1-11
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• 1975

The present experiments were carried out to investigate the active center of sodium and potassium ion activated adenosine triphosphatase. An ATPase, activated by sodium ion Plus potassium ion in the presence of magnesium ion, and inhibited by ouabain, has been obtained from rabbit red cell ghosts. The ATPase activity was measured by inorganie phosphate released from ATP. From this values of the measured inorganic phosphate, the activity of ATPase was calculated. The following results were observed. 1. The activity of $(Na^++K^+)-ATPase$ is inhibited by ouabain. This effect may not be due to an effect on sulfhydryl groups, amino groups, carboxyl groups, imidazole groups and hydroxyl groups. 2. The $(Na^++K^+)$-activated enzyme system is inhibited by p-chloromercuribenzoate and by d nitroflurobenzene, and this effect may be due to an effect on sulfhydryl groups. These results indicate that the sulfhydryl groups is attached to sodium-potassium dependent adenosine triphosphate, an aspect of the pump. 3. The $(Na^++K^+)-activated$ enzyme system is inhibited by maleic anhydride and this inhibition is reversed by lysine. This Seems to indicate that the active center of this enzyme is the amino groups. 4. The $(Na^++K^+)$-activated enzyme system is inhibited by iodoacetamide and this inhibition is reversed by the simultaneous present of cysteine and aspartic acid in the suspension medium. This result indicates that this enzyme contains sulfhydryl groups and carboxyl groups. 5. The $(Na^++K^+)-ATPase$ activity is accelerated by adrenaline and this effect is abolished by aspartic acid. This effect of aspartic acid indicate that carboxyl group might be involved in the hydrolysis of ATP by the enzyme system. On the hydrolysis of ATP by the enzyme system. On the basis of these experiments it f·as suggested that the active center of $(Na^++K^+)-activated$ ATPase contains sulfhydryl groups, amino groups and carboxyl groups.

• Journal of Dairy Science and Biotechnology
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• v.33 no.1
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• pp.83-91
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• 2015

Yogurt is a product of the acidic fermentation of milk, which affects the survival of lactic acid bacteria (LAB). The aim of this present study was to examine the survival and acid stress response of Lactobacillus rhamnosus GG to low pH environment. The survival of LAB in commercial yogurt was measured during long-term storage. The enumeration of viable cells of LAB was determined at 15-day intervals over 52-weeks at $5^{\circ}C$. L. acidophilus, L. casei, and Bifidobacterium spp. showed low viability. However, L. rhamnosus GG exhibited excellent survival throughout the refrigerated storage period. At the end of 52-weeks, L. rhamnosus GG survived 7.0 log10 CFU/mL. $F_0F_1$ ATPase activity in L. rhamnosus GG at pH 4.5 was also evaluated. The ATPase activities of the membranes were higher when exposed at pH 4.5 for 24 h. The survival of L. rhamnosus GG was attributable to the induction in $F_0F_1$ ATPase activity. In addition, the mRNA expression levels of acid stress-inducible genes at low pH were investigated by qRT-PCR. clpC and clpE genes were up-regulated after 1 h, and atpA and dnaK genes were up-regulated after 24 h of incubation at pH 4.5. These genes could enhance the survival of L. rhamnosus GG in the acidic condition. Thus, the modulation of the enzymes or genes to assist the viability of LAB in the low pH environment is thought to be important.

• Bulletin of the Korean Chemical Society
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• v.32 no.2
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• pp.531-535
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• 2011

It was regarded that the $^{31}P$ resonances of inherent nucleotides in $F_1$-ATPase (EF1), as large as 380KDa, could not be observed by $^{31}P$ NMR spectroscopy. However, our $^{31}P$ NMR spectroscopy could differentiate between different nucleotide binding sites on EF1 from Escherichia coli. When EF1 was prepared in the absence of $Mg^{2+}$, EF1 contained only ADP. Multiple $^{31}P$ resonances from $\beta$-phosphates of ADP bound to the EF1 were observed from the enzyme prepared without $Mg^{2+}$, suggesting asymmetry or flexibility amongst nucleotide binding sites. $^{31}P$ resonances from enzyme bound ATP could be observed only from EF1, when the enzyme was prepared in the presence of $Mg^{2+}$. This $Mg^{2+}$ dependent ATP binding was very tight that, once bound, nucleotide could not be removed even after removal of $Mg^{2+}$. $^{31}P$ NMR proved to be a valuable tool for investigating phosphorous related enzymes.

• Bulletin of the Korean Chemical Society
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• v.33 no.7
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• pp.2419-2422
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• 2012

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2001.06a
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• pp.123-124
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• 2001

• Journal of Ginseng Research
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• v.19 no.2
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• pp.127-133
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• 1995

The complete open reading frame (ORF) of o-subunit of the $F_1$ ATP synthase (atPA) in Korean ginseng mitochondria was identified by the sequence similarity with atPA genes in other plant mitochondria. The sequence alignment showed that the common translation initiation codon, ATG, in plant genes was replaced with GTG valid codon in Korean ginseng. The atPA gene from GTG to TGA termination codon was 1524 nucleotides long, and the sequence homology of nucleotides and deduced amino acids revealed high values of 92~97%. A deletion event of 6 nucleotides was observed at the 1468th nucleotide from the GTG in Korean ginseng, in contrast to that at the 1450th in other plants such as pea, common bean, soybean, sugar beet, and radish. An unidentified open reading frame (on7) was observed upstream of atmA ORF. No other ATG as an initiation codon was detected in the region between off and atmA ORF in Korean ginseng, although a pyrimidine cluster "TTTTCTTTT" was located in this region as in Oenothera and maize genes. It could be supposed that GTG codon in atpA gene of Korean ginseng mitochondria would act as an initiation codon as in microbial genes.ial genes.

• Animal cells and systems
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• v.14 no.1
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• pp.1-10
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• 2010

Previously we showed that CHIP, a co-chaperone of Hsp70 and E3 ubiquitin ligase, can promote the degradation of mutant SOD1 linked to familial amyotrophic lateral sclerosis (fALS) via a mechanism not involving SOD1 ubiquitylation. Here we present evidence that CHIP functions in the interaction of mutant SOD1 with 26S proteasomes. Bag-1, a coupling factor between molecular chaperones and the proteasomes, formed a complex with SOD1 in an hsp70-dependent manner but had no direct effect on the degradation of mutant SOD1. Instead, Bag-1 stimulated interaction between CHIP and the proteasome-associated protein VCP (p97), which do not associate normally. Over-expressed CHIP interfered with the association between mutant SOD1 and VCP. Conversely, the binding of CHIP to mutant SOD1 was inhibited by VCP, implying that the chaperone complex and proteolytic machinery are competing for the common substrates. Finally we observed that mutant SOD1 strongly associated with the 19S complex of proteasomes and CHIP over-expression specifically reduced the interaction between S6/S6' ATPase subunits and mutant SOD1. These results suggest that CHIP, together with ubiquitin-binding proteins such as Bag-1 and VCP, promotes the degradation of mutant SOD1 by facilitating its translocation from ATPase subunits of 19S complex to the 20S core particle.

• Korean Journal of Veterinary Research
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• v.28 no.2
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• pp.227-239
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• 1988

In order to investigate the morphological characteristics of dendritic cells in the mammary gland, the appearance on the clear cells(CLs) or ATPase-positive dendritic cells(APDCs) have been observed by the light microscope. The results obtained were summarized as follows: CLs were observed in the mammary tissues of the experimental animals, such as mice, rats, guinea pigs, rabbits, cats, dogs, pigs, cows and Korean native goats, and these CLs were confirmed as the ATPase-positive cells of typical dendritic appearance(APDCs), The APDCs were distributed in between the secretory epithelial cells, between the secretory epithelial cells and the myoepithelial cells, the basal area of the secretory epithelial cells, the interalveolar and interlobular connective tissues, and in between the epithelial cells of secretory duct. The APDCs were observed more frequently during the middle period of lactation than the other periods, and were irregularly or uniformly distributed according to the location. During the middle period of lactation, there were notable quantitative differences in the APDSs depending on the mammary glands of mice, rats, guinea pigs, rabbits and cats, The most prominent differences were recognized among the mice, guinea pigs and cats. The number of AP DCs per unit area was statistically fewer in the guinea pigs($209.07{\pm}51.75cells/mm^2$) than in the mice($221.00{\pm}50.94cells/mm^2$) and cats($223.56{\pm}49.68cells/mm^2$) (respectively, p<0.05, p<0.05). Among the A/J, DBA/2, C57BL/6 and NIH(GP) mice, the mean densities of APDCs was statistically significantly fewer in the DBA/2($196.65{\pm}43.47cells/mm^2$) than in the C57BL/6($248.40{\pm}41.40cells/mm^2$) and NIH(GP) ($235.98{\pm}55.89cells/mm^2$) (respectively, p<0.0000, p<0.0000), however no significant difference between the C57BL/6 and the NIH(GP) was recognized (p>0.1). Among the F344, SD and W rats, the statistical analysis were confirmed that there were significantly fewer APDCs in the F344($198.72{\pm}47.61cells/mm^2$) than in the SD($227.70{\pm}41.40cells/mm^2$) and W($223.56{\pm}49.68cells/mm^2$) (respectively, p<0.0000, p<0.0001), however no significant difference between the SD and the W was recognized(p>0.1). The mean difference between the inbred and the noninbred counts in the mice was statistically significant (p<0.0001), and the similar result was presented in the rats(p<0.0000).

• The Korean Journal of Physiology
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• v.19 no.2
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• pp.203-213
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• 1985

This study was carried out to investigate whether the K-pNPPase activity in renal cortical slices can be used as an index for measuring the activity of $Na^+-K^+$ exchange pump. The K-pNPPase activity, Ouabain-sensitive oxygen consumption add intracellular electrolytes content in slices, and Na-K-ATPase activity in microsome were measured and the effects of ouabain and vanadate on these were observed. The results are as follows : 1) p-NPPase activity in slices increased linearly with incubation time during 60 minutes, and $K^+$-dependent, ouabain-sensitive fraction was about 55% of total p-NPPase activity. This value was almost the same through out the incubation time. 2) The concentrations of ouabain and vanadate for 50f inhibition of K-pNPPase activity were$7.0{\times}10^{-6}M$ and $1.3{\times}10^{-5}M$, respectively. 3) The ouabain-sensitive oxygen consumption in slices was reduced to 50% of control value by $6.3{\times}10^{-6}M$ ouabain or $2.5{\times}10^{-5}M$ vanadate. These concentrations were similar to those for 50% inhibition of K-pNPPase activity. 4) The trends of intracellular electrolytes change by ouabain and vanadate were similar to those of the change in K-pNPPase activity. 5) The Na-K-ATPase activity in microsome prepared from renal cortex was completely inhibited by $10^{-3}M$ ouabain or $10^{-3}M$ vanadate and the concentration for 50% inhibition was $1.2{\times}10^{-6}M$ in ouabain and $1.6{\times}10^{-6}M$ in vanadate, which were much lower than those for K-pNPPase activity or ouabain-sensitive oxygen consumption in slices. These results indicate that K-pNPPase activity measured in renal cortical slices is a better index for evaluating $Na^+-K^+$ exchange pump activity than Na-K-ATPase activity measured in microsome.