• BMB Reports
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• v.45 no.9
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• pp.532-537
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• 2012

P18, a member of the INK4 family of cyclin-dependent kinase inhibitors, is a tumor suppressor protein and plays a key cell survival role in a variety of human cancers. Under pathophysiological conditions, the INK4 group proteins participate in novel biological functions associated with neuronal diseases and oxidative stress. Parkinson's disease (PD) is characterized by loss of dopaminergic neurons, and oxidative stress is important in its pathogenesis. Therefore, we examined the effects of PEP-1-p18 on oxidative stress-induced SH-SY5Y cells and in a PD mouse model. The transduced PEP-1-p18 markedly inhibited 1-methyl-4-phenyl pyridinium-induced SH-SY5Y cell death by inhibiting Bax expression levels and DNA fragmentation. Additionally, PEP-1-p18 prevented dopaminergic neuronal cell death in the substantia nigra of a 1-methyl-4-phenyl-1,2,3,6,-tetrahydropyridine-induced PD mouse model. These results indicate that PEP-1-p18 may be a useful therapeutic agent against various diseases and is a potential tool for treating PD.

• Asian Journal of Turfgrass Science
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• v.8 no.1
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• pp.13-18
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• 1994

$CO_2$와 질소동화작용에 있어서의 잎과 줄기간의 세포간 관계가 잔디군락의 자연 환경 상태하에서 자라는 Portulaca oleracea 에서 조사되었다. 기공이 줄기에서는 관찰되지 않는 반면 잎에서는 $1cm^2$당 3,275개가 나타났다. 어린 쇠비름 잎의 기공의 조헝운 범에누누 높고 낮에는 낮다. 최고 활성을 갖는 마디의 순서는 위에서 아래로 떨어짐에 따라 변화한다.P.oleracea 의 줄기조직은 CMA의 최고 활성을 나타내었으나 잎에서는 CMA의 활성이 나타나지 않았다. 빠른 산의 성화는 새벽에 원줄기에서 보여지나 줄기는 서서히 증가하는 것 밖에 관찰되지 않는다. RuPB carboxy-lase의 활성은 거의 관찰 되지 않는다. 특히 잎새에서의 PEP carboxylase의 활성은 이른 아침에 줄기에서는 낮고 잎에서는 매우 높음을 보여준다. 이런 결과는 새벽에 열려진 기공을 통과할$CO_2$가 PEP carboxylase에 의해 잎에서 동화되고 $C_4$생산물이 줄기로 이동함을 나타낸다. Nitrate 축적과 nitrate reductase, nitrite reductase, glutamine symithetase, gluamate symthase, glutamade dehydrogenase의 농도는 잎보다 줄기에서 더 높았고 밤보다 낮에 더 높다. 이것은 뿌리를 통해 흡수된 nitrate의 상당한 양이 줄기에서 동화되고 줄기 조직을 통해 잎으로 이동되어 거기에서 감소된다.

• The Korean Journal of Mycology
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• v.24 no.4 s.79
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• pp.293-304
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• 1996

A bacterial strain, KSl, possessing strong antifungal activity was isolated from soil samples of ginseng fields and identified as Bacillus subtilis. In greenhouse test, the culture filtrate of B. subtilis KS1 showed strong protective effect against several fungal diseases of agricultural plants such as cucumber gray mold and wheat leaf rust. In addition, the crude butanol fraction of the culture filtrate exhibited antagonistic effect against several fungi including plant or human pathogens, such as Botrytis maydis, Chytridium lagenarium and Candida albicans. The antifungal compound, SW1, produced by B. subtilis KS1 was purified through consecutive chromatographic separations on a pep-RPC column and a ${\mu}$ Bondapak $C_{18}$ reverse phase column. Temperature and pH showed little effect on the stability of the compound in the ranges $-20-121^{\circ}C$ and pH 4.0-10.0, respectively. The composition and structural characteristics of SW1 were analysed by HPLC and by $^1H-,\;^1H-^1H-COSY$, NOESY, COSY-NOESY and HOHAHA NMR spectroscopy, respectively, which revealed that the compound belongs to iturin A, a typical cyclic antifungal compound produced by B. subtilis. In contrast to the previously reported iturin A compounds which have one or no $-CH_3$ side chain in the hydrophobic hydrocarbon chain of ${\beta}-amino$ acids, SW1 was shown to have a ${\beta}-amino$ acid containing 12-carbon skeleton with two $-CH_3$ side chains.

• Journal of Microbiology and Biotechnology
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• v.18 no.4
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• pp.746-753
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• 2008

The hprK gene encoding bifunctional HPrK/P (kinase/phosphorylase) was cloned from L. mesenteroides SY1, a strain isolated from kimchi. hprK was transcribed as a monocistronic gene. His-tagged HPrH16A and HPrK/P were produced in E. coli BL21 (DE3) using pET26b(+) and purified. HPrK/P phosphorylation assay with purified proteins showed that the kinase activity of HPrK/P increased at slightly acidic pHs. Divalent cations such as $Mg^{2+}$ and $Mn^{2+}$ and glycolytic intermediates such as fructose-1, 6-bisphosphate (FBP) and phosphoenolpyruvate (PEP) increased the kinase activity of HPrK/P, but inorganic phosphate strongly inhibited it. Kinetic studies for the kinase activity of HPrK/P showed that the apparent $K_m$ values were 0.18 and $14.57{\mu}M$ for ATP and HPr, respectively. The $K_m$ value for the phosphorylase activity of HPrK/P was $14.16{\mu}M$ for P-Ser-HPr (HPr phosphorylated at the serine residue).

• Archives of Pharmacal Research
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• v.18 no.1
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• pp.12-17
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• 1995

It is essential to clone the preptide transporter in order to obtain better understanding of its molecular structure, regulation, and substrate specificity. Characteristics of an endogenous peptide transporter in oocytes were studied along with expression of an exogenous protor/peptide cotransporter from rabbit intestine. And further efforts toward cloning the transporter were performed. The presence of an endogenous peptide transporter was detected in Xenopus laevis oocytes by measuring the uptake of $0.25/{mu}M(10{\;}{\mu}Ci/ml)[^3H]$-glycylsarcosine (Gly-Sar) at pH 5.5 with or without inhibitors. Yptake of Gly-Sae in oocytes was significantly inhibited by $25{\mu}M$ glycine nd sarcosine. This result suggests that a selective transporter is involved in the endogneous uptake of dipeptides. Collagenase treatment of oocytes used to strip oocytes from ovarian follicles did not affect the Gly-Sar uptake. Changing pH from 5.5 to 7.5 did not affect the Gly-Sae uptake significantly, suggesting no depedence of the endogenous transporter on a transmembrane proton gradient. An exogenous $H^+/pep-tide$ contransported was expressed after microinjection of polyadenylated messenger ribonucleic acid $[poly(A)^+ -mRNA]$ obtained from rabbit small intestine. The Gly-Sar uptake in mRNA-injected oocytes was 9 times thigher than that in water-injected oocyltes. Thus, frog occytes can be utilized fro expression cloning of the genes encoding intestinal $H^+$peptide contransporters. Size fractionation of mRNA was successfully obtained using this technique.