• Applied Biological Chemistry
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• v.25 no.3
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• pp.155-160
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• 1982

Claviceps purpurea PRL 1980 produces a fluorescent reddish brown pigment in the alkaloid production medium. When D,L-tryptophan $[side\;chain-3-^{14}C]$ was administered into the production medium, the radioactive pigment and 5-hydroxytryphan were isolated from the cultures. Conversion of tryptophan to 5-hydroxytryptophan in vivo was shown by an isotopic trapping procedure. 5-hydroxytryptophan isolated from the cultures contained appreciable radioactivity and was recrystallized to constant specific radioactivity. The injection of the $^{14}C-labelled$ 5-hydroxytryptophan showed an incorporation of radioactivity into brown pigment significantly higher than that of tryptophan. The brown pigment produced by Claviceps purpurea PRL 1980 seems to be derived from tryptophan through 5-hyrdroxytryptophan.

• Journal of Life Science
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• v.22 no.8
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• pp.1009-1017
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• 2012

The orf282 gene of Rhodobacter sphaeroides is located between the ccoNOQP operon encoding $cbb_3$ terminal oxidase and the fnrL gene encoding an anaerobic activator, FnrL. Its function remains unknown. In an attempt to reveal the function of the orf282 gene, we disrupted the gene by deleting a portion of the orf282 gene and constructed an orf282-knockout mutant. Two FnrL binding sites were found to be located upstream of orf282, and it was demonstrated that orf282 is positively regulated by FnrL. The orf282 gene is not involved in the regulation of spectral complex formation. The $cbb_3$ oxidase activity detected in the orf282 mutant was comparable to that in the wild-type sample, indicating that the orf282 gene is not involved in the regulation of the ccoNOQP operon and the biosynthesis of the cbb3 cytochrome c oxidase. The elevated promoter activity of the nifH and nifA genes, which are the structural genes of nitrogenase and its regulator, respectively, in the orf282 mutant, suggests that the orf282 gene product acts as a negative effector for nifH and nifA expression.

• Journal of Ginseng Research
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• v.37 no.4
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• pp.413-424
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• 2013

Korean Red Ginseng extract (KRGE) is a traditional herbal medicine utilized to prevent endothelium dysfunction in the cardiovascular system; however, its underlying mechanism has not been clearly elucidated. We here examined the pharmacological effect and molecular mechanism of KRGE on apoptosis of human umbilical vein endothelial cells (HUVECs) in a serum-deprived apoptosis model. KRGE protected HUVECs from serum-deprived apoptosis by inhibiting mitochondrial cytochrome c release and caspase-9/-3 activation. This protective effect was significantly higher than that of American ginseng extract. KRGE treatment increased antiapoptotic Bcl-2 and Bcl-$X_L$ protein expression and Akt-dependent Bad phosphorylation. Moreover, KRGE prevented serum deprivation-induced subcellular redistribution of these proteins between the mitochondrion and the cytosol, resulting in suppression of mitochondrial cytochrome c release. In addition, KRGE increased nitric oxide (NO) production via Akt-dependent activation of endothelial NO synthase (eNOS), as well as inhibited caspase-9/-3 activities. These increases were reversed by co-treatment of cells with inhibitors of eNOS and phosphoinositide 3-kinase (PI3K) and pre-incubation of cell lysates in dithiothreitol, indicating KRGE induces NO-mediated caspase modification. Indeed, KRGE inhibited caspase-3 activity via S-nitrosylation. These findings suggest that KRGE prevents serum deprivation-induced HUVEC apoptosis via increased Bcl-2 and Bcl-$X_L$ protein expression, PI3K/Akt-dependent Bad phosphorylation, and eNOS/NO-mediated S-nitrosylation of caspases. The cytoprotective property of KRGE may be valuable for developing new pharmaceutical means that limit endothelial cell death induced during the pathogenesis of vascular diseases.

• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1659-1664
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• 2012

TSAHC [4'-(p-toluenesulfonylamido)-4-hydroxychalcone] is a promising antitumorigenic chalcone compound, especially against TM4SF5 (four-transmembrane L6 family member 5)-mediated hepatocarcinoma. We evaluated the potential of TSAHC to inhibit the catalytic activities of nine cytochrome P450 isoforms and of P-glycoprotein (P-gp). The abilities of TSAHC to inhibit phenacetin O-deethylation (CYP1A2), coumarin 6-hydroxylation (CYP2A6), bupropion hydroxylation (CYP2B6), amodiaquine N-deethylation (CYP2C8), diclofenac 4-hydroxylation (CYP2C9), omeprazole 5-hydroxylation (CYP2C19), dextromethorphan O-demethylation (CYP2D6), chlorzoxazone 6-hydroxylation (CYP2E1), and midazolam 1'-hydroxylation (CYP3A) were tested using human liver microsomes. The P-gp inhibitory effect of TSAHC was assessed by [$^3H$]digoxin accumulation in the LLCPK1-MDR1 cell system. TSAHC strongly inhibited CYP2C8, CYP2C9, and CYP2C19 isoform activities with $K_i$ values of 0.81, 0.076, and $3.45{\mu}M$, respectively. It also enhanced digoxin accumulation in a dose-dependent manner in the LLCPK1-MDR1 cells. These findings indicate that TSAHC has the potential to inhibit CYP2C isoforms and P-gp activities in vitro. TSAHC might be used as a nonspecific inhibitor of CYP2C isoforms based on its negligible inhibitory effect on other P450 isoforms such as CYP1A2, CYP2A6, CYP2B6, CYP2D6, CYP2E1, and CYP3A.

• Journal of Life Science
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• v.24 no.7
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• pp.798-803
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• 2014

Cathepsin D (CtsD), an aspartyl peptidase, is involved in apoptosis, resulting in the release of cytochrome C from mitochondria in cells. Here, we investigated microRNA regulation of CtsD expression in 3T3-L1 cells First, we observed the expression of CtsD in cells in response to doxorubicin (Dox). As expected, the level of CtsD mRNA was increased in 3T3-L1 cells exposed to Dox in a dose-dependent manner. Cellular viability of ectopically expressed CtsD cells was also decreased. Next, we used the miRanda program to search for particular microRNA targeting CtsD. MiR-145 was selected as a putative controller for CtsD because miR-145 had a high mirSVR score. In a reporter assay, the luciferase activity of cells containing the CtsD 3'-UTR region was decreased in cells transfected with miR-145 mimic compared to that of a control. The level of CtsD expression was down-regulated in preadipocytes ectopically expressing miR-145 and up-regulated by an miR-145 inhibitor. Cells also suppressed miR-145 expression when exposed to Dox. The miR-145 inhibitor reduced the cellular viability of 3T3-L1 cells. Taken together, these data suggest that miR-145 regulates CtsD-mediated cell death in adipocytes. These findings may have valuable implications concerning the molecular mechanism of CtsD-mediated cell death in obesity, suggesting that CtaD could be a useful therapeutic tool for the prevention and treatment of obesity by regulating fat cell numbers.

• Animal Systematics, Evolution and Diversity
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• v.38 no.1
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• pp.14-19
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• 2022

Leptochiton Gray, 1847 is one of the most ancient chiton groups which includes more than 130 species that occur in cold and deep waters worldwide. Due to their small-sized body, they are often confused as juveniles of other chiton species. Moreover, lack of morphological information makes species identification of this group very challenging. To date, only two Leptochiton species(L. fuliginatus and L. rugatus) have been reported from Korean waters. In this study, we found L. hakodatensis(Thiele, 1909) for the first time in Korea and described microscopic morphological characters of valves (tegmentum sculpture), girdle scale, and radula using a scanning electron microscopy (SEM). Leptochiton hakodatensis is morphologically similar to L. fuliginatus and L. rugatus, but differently characterized by having dorso-ventrally rounded (not carinated) intermediate valves, girdle (perinotum) scales sculptured with 4-7 longitudinal ribs, and bicuspid major lateral teeth of radula. In addition to morphological examination, we determined the partial mitochondrial cytochrome c oxidase subunit I(cox1) as a DNA barcode sequence information. This is the first report that describes microscopic characters (tegmentum of valves, girdle structure, and radula) of L. hakodatensis using a SEM. This study provides a morphological basis for describing Leptochiton species and discovery of a "hidden" species of this genus.

• Journal of Microbiology and Biotechnology
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• v.22 no.7
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• pp.917-922
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• 2012

Homology modeling of Streptomyces peucetius CYP147F1 was constructed using three cytochrome P450 structures, CYP107L1, CYPVdh, and CYPeryF, as templates. The lowest energy SPCYP147F1 model was then assessed for stereochemical quality and side-chain environment by Accelrys Discovery Studio 3.1 software. Further activesite optimization of the SPCYP147F1 was performed by molecular dynamics to generate the final SPCYP147F1 model. The substrate limonene was then docked into the model. The model-limonene complex was used to validate the active-site architecture, and functionally important residues within the substrate recognition site were identified by subsequent characterization of the secondary structure. The docking of limonene suggested that SPCYP147F1 would have broad specificity with the ligand based on the two different orientations of limonene within the active site facing to the heme. Limonene with C7 facing the heme with distance of $3.4{\AA}$ from the Fe was predominant.

• Animal Systematics, Evolution and Diversity
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• v.33 no.2
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• pp.131-135
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• 2017

Asteroid specimens of the genus Luidia were collected at a depth of 95-100 m in the Korea Strait by bottom trawling in April 2016. The specimens were identified as Luidia avicularia Fisher, 1913 (Luidiidae: Paxillosida) based on morphological characteristics and molecular phylogenetic analyses, and the species is new to the Korean fauna. A 648-bp partial nucleotide sequence of mitochondrial cytochrome c oxidase I (mt-COI) gene was obtained from Korea, and then was compared to sequences of related species stored in GenBank using molecular phylogenetic analyses. No sequence differences were detected between the L. avicularia mt-COI gene sequences from Korea and China, and the species described in this report was clearly distinct from L. maculata, which was previously reported in Korean fauna. Three Luidia species have been reported in Korea.

• YAKHAK HOEJI
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• v.43 no.6
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• pp.827-833
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• 1999

In this study, we have investigated the effect of Biphenyl Dimethyl Dicarboxylate (DDB), a synthetic analogue of Schizandrin C isolated from Schizandrae Fructus on cytochrome $P_450$ lAl and 2Bl, and the protective mechanism against $CCl_4-induced$ hepatotoxicity in rat liver. After DDB was administered into male rats for different periods of time (1~7 days) and with different doses (25, 50, 100 and 200 mg/kg), mRNA levels of CYPlAl were measured by polymearse chain reaction (PCR) and assayed the activities of CYPlAl specific ethoxyresorufin-O-dealkylase (EROD) and CYP2Bl specific benzyloxyresorufin-O-dealkylase (BROD). DDB treatment resulted in increase in CYP2Bl mRNA level and BROD activity, whereas there was no change in CYPlAl mRNA level and EROD activity. This effect of DDB was time-and dose-dependent and reached maximal level by 3 day and 200 mg/kg treatment. In addition, rats were pre-treated with DDB at doses of 25, 50 or 100 mg/kg daily for 4 days, 3-hr after final treatment on the 4th day, $CCl_4$ 0.3ml/kg was intraperitonially injected into the rats to examine the effect of DDB on $CCl_4-induced$ hepatic injury. Serum levels of ALT and AST were determined and histopathological examination was done in rat liver. Furthermore, we have measured hepatic microsomal malondialdehyde(MDA) level, a parameter of lipid peroxidation. Based on serum ALT level and lipid peroxidation, pretreatment of DDB, 50 mg/kg appeared the most protective effect against $CCl_4-induced$ heapatotoxity. These results indicate that DDB stimulates CYP2Bl mRNA level and BROD activity in time and dose dependent manner and suggest that protective effect of DDB on $CCl_4-induced$ hepatotoxicity may be mediated through free radical scavenging.

• Korean Journal of Food Science and Technology
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• v.52 no.3
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• pp.263-273
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• 2020

In this study, in order to confirm the ameliorative effects of onion (Allium cepa L.) flesh and peel on amyloidbeta (Aβ)-induced cognitive dysfunction, we evaluated their in vitro neuroprotection and in vivo cognitive functions. As the result of in vitro neuroprotection, the protective effect of the ethyl acetate fraction of onion flesh (EOF) on Aβ-induced cytotoxicity was similar to that of the ethyl acetate fraction of onion peel (EOP). In the behavioral tests, the EOF and EOP effectively improved the Aβ-induced learning and memory impairments. For this reason, it could be concluded that the EOF and EOP improved the antioxidant activities (superoxide dismutase, oxidized glutathione/total glutathione, and malondialdehyde) in brain tissue. In addition, the EOF and EOP effectively activated mitochondrial functions by protecting the mitochondrial membrane potential, ATP, mitochondria-mediated protein (BAX and cytochrome c), and caspase 3/7 activities. The EOF and EOP also improved the cholinergic system (acetylcholinesterase and acetylcholine). Therefore, we suggest that onion could be used for management of Aβ-induced cognitive dysfunction.