• Journal of Microbiology and Biotechnology
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• v.25 no.6
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• pp.872-879
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• 2015

Many strains of Bacillus cereus cause gastrointestinal diseases, and the closely related insect pathogen Bacillus thuringiensis has also been involved in outbreaks of diarrhea. The diarrheal diseases are attributed to enterotoxins. Sixteen reference strains of B. cereus and nine commercial and 12 reference strains of B. thuringiensis were screened by PCR for the presence of 10 enterotoxigenic genes (hblA, hblC, hblD, nheA, nheB, nheC, cytK, bceT, entFM, and entS), one emetogenic gene (ces), seven hemolytic genes (hlyA, hlyII, hlyIII, plcA, cerA, cerB, and cerO), and a pleiotropic transcriptional activator gene (plcR). These genes encode various enterotoxins and other virulence factors thought to play a role in infections of mammals. Amplicons were successfully generated from the strains of B. cereus and B. thuringiensis for each of these sequences, except the ces gene. Intriguingly, the majority of these B. cereus enterotoxin genes and other virulence factor genes appeared to be widespread among B. thuringiensis strains as well as B. cereus strains.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.4 s.48
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• pp.479-483
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• 2004

An attempt was made to develop a proteinchip for screening of MITF (microphthalmia transcription factor) inhibitor. Binding of MITF to E-box causes transcription of several pigmenting genes including tyrosinase gene. We investigated binding of MITF and its DNA binding site (E-box) using a protein-DNA chip with various detection methods including flurorescence (Cyt3). SPR (surface plasmon resonance) and SPRi (surface plasmon resonance imaging). A fusion protein (MITF-Maltose Binding Protein) was attached on the glass plate by chemical modification. An inhibitory synthetic DNA oligomer, artificially designed based on the E-box sequence, inhibited the binding of MITF and E-box. These results showed the potentials of flurorescence-based MITF protein chip as a microarray for high throughput screening (HTS) system of depigmenting agents.

• Parasites, Hosts and Diseases
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• v.51 no.2
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• pp.165-175
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• 2013

The fear that schistosomes will become resistant to praziquantel (PZQ) motivates the search for alternatives to treat schistosomiasis. The antimalarials quinine (QN) and halofantrine (HF) possess moderate antischistosomal properties. The major metabolic pathway of QN and HF is through cytochrome P450 (CYP) 3A4. Accordingly, this study investigates the effects of CYP3A4 inhibitor, ketoconazole (KTZ), on the antischistosomal potential of these quinolines against Schistosoma mansoni infection by evaluating parasitological, histopathological, and biochemical parameters. Mice were classified into 7 groups: uninfected untreated (I), infected untreated (II), infected treated orally with PZQ (1,000 mg/kg) (III), QN (400 mg/kg) (IV), KTZ (10 mg/kg)+QN as group IV (V), HF (400 mg/kg) (VI), and KTZ (as group V)+HF (as group VI) (VII). KTZ plus QN or HF produced more inhibition (P<0.05) in hepatic CYP450 (85.7% and 83.8%) and CYT b5 (75.5% and 73.5%) activities, respectively, than in groups treated with QN or HF alone. This was accompanied with more reduction in female (89.0% and 79.3%), total worms (81.4% and 70.3%), and eggs burden (hepatic; 83.8%, 66.0% and intestinal; 68%, 64.5%), respectively, and encountering the granulomatous reaction to parasite eggs trapped in the liver. QN and HF significantly (P<0.05) elevated malondialdehyde levels when used alone or with KTZ. Meanwhile, KTZ plus QN or HF restored serum levels of ALT, albumin, and reduced hepatic glutathione (KTZ+HF) to their control values. KTZ enhanced the therapeutic antischistosomal potential of QN and HF over each drug alone. Moreover, the effect of KTZ+QN was more evident than KTZ+HF.

• BMB Reports
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• v.38 no.4
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• pp.432-439
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• 2005

$Ca^{2+}$/calmodulin transduction pathways have been implicated in mediating stress response and tolerance in plants. Here, three genes encoding calmodulin (Cam) members of the EF-hand family of $Ca^{2+}$-binding proteins were identified from Oryza sativa L. databases. Complementary DNA for each of the calmodulin genes, OsCam1, OsCam2, and OsCam3 were sequenced. OsCam1 and OsCam2 encode a conventional 148-amino acid calmodulin protein that contains four characteristic $Ca^{2+}$-binding motifs. OsCam3 encode a similar protein with a 38-amino-acid extension containing a putative prenylation site (CVIL) at the carboxyl terminus. RT-PCR showed that each of the genes is expressed in leaves and roots of 2-week old rice seedlings. By RNA gel blot analysis, OsCam1 mRNA levels strongly increased in response to NaCl, mannitol and wounding treatments. In contrast, OsCam2 mRNA levels were relatively unchanged under all conditions investigated. NaCl treatment and wounding also increased the OsCam3 mRNA level, but in a more transient manner. Our results indicate that although the expression of genes encoding different calmodulin isoforms is ubiquitous, they are differentially regulated by various stress signals. In addition, we have demonstrated that the calcium-channel blocker lanthanum chloride inhibited the induction of OsCam1 gene expression by both NaCl and mannitol treatments. These results suggest that osmotic stress induced expression of OsCam1 gene requires the $[Ca^{2+}]_{cyt}$ elevation that is known to occur in response to these stimuli.

• Journal of Microbiology
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• v.40 no.3
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• pp.211-218
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• 2002

A 4.8-kb DNA fragment encoding the P-450 type hydroxylase and ferredoxin genes was cloned from Pseudonocardia autotrophica IFO 12743 that can convert vitamin D$\_$3/ into its hydroxylated active forms. In order to isolate the P-450 gene cluster in this organism, we designed PCR primers on the basis of the regions of an oxygen binding site and a heme ligand pocket that are general characteristics of the P-450 hydroxylase. Sequencing analysis of the BamHI fragment revealed the presence of four complete and one incomplete ORFs, named PauA, PauB, PauC, and PauD, respectively. As a result of computer-based analyses, PauA and PauB have homology with enoyl-CoA hydratase from several organisms and the positive regulators belonging to the tetR family, respectively. PauC and PauD show similarity with SuaB/C proteins and ferredoxins, respectively, which are composed of P-450 monooxygenase systems for metabolizing two sulfonylurea herbicides in Streptomyces griseolus PauC shows the highest similarity with another CytP-450$\_$Sca2/ protein that is responsible for production of a specific HMG-CoA reductase inhibitor, pravastatin, in S. carbophilus. Cultures of Steptomyces lividans transformant, containing the P-450 gene cluster on the pWHM3 plasmid, was unable to convert vitamin D$\_$3/ to its hydroxylated forms.

• Korean Journal of Veterinary Research
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• v.44 no.3
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• pp.323-327
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• 2004

The purpose of the present experiment was to investigate the micronuclei(MN) frequency in cytokinesis-blocked(CB) cells after various doses of gamma-rays in pig (Landrace, male, 3-month-old) and so to contribute to the clarification of the question whether these species are suitable as a target organism in the test system. The frequencies of binucleated cells, and gamma-ray-induced MN in CB cells at several doses were measured in three donors. The peaks of binucleated lymphocyte formation(22%) were found at a concentration of 2% phytohaemagglutinin(PHA) and $4{\mu}g/ml$ Cytochalasin B(Cyt-B) in pig at 72 hours after incubation. Measurements performed after irradiation showed a dose-related increases in MN frequency in each of the donors studied. When analysed by linear-quadratic model the line of best fit was $y=0.0183D+0.0124D^2+0.0133$(y = number of MN/CB cells and D=irradiation dose in Gy). In conclusion, the results demonstrate that it appears feasible to use pig as target organisms in the micronucleus test to estimate the cytogenetic damage caused by ionizing radiations or, potentially, chemical compounds.

• Animal cells and systems
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• v.3 no.1
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• pp.89-96
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• 1999

Nucleotide sequences of a 501 base-pair (bp) fragment in the mitochondrial cytochrome b (cyt b) gene were analyzed for 12 populations of Rana rugosa from Korea and Japan using a polymerase chain reaction (PCR) and direct silver sequencing. Two genetically distinct groups (type-A and type-B) were found in Korea. Type-A was found throughout most of South Korea and type-B was restricted to the mid-southeastern regions (Samchok, Yongdok, Chongsong and Pohang). But in the Tonghae population, both types were found. The level of mitochondrial DNA (mtDNA) sequence differences ranged from 0% to .0.8% among six populations of type-A, and 0 to 1.0% among 4 populations of type-B. However, sequence differences between type-A and type-B ranged from 5.4% to 6.6%, Using Kimura's two-parameter distance, the level of genetic sequence divergence between type-A and type-B was 6.7%. The Japanese R. rugosa was clustered very far from the Korean R. rugosa with 14.7%. In the neighbor-joining and UPGMA tree, all Korean samples were grouped, but subdivided into two types in 99% of the bootstrap iteration.

• Molecules and Cells
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• v.38 no.12
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• pp.1054-1063
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• 2015

Mitochondria play a crucial role in eukaryotic cells; the mitochondrial electron transport chain (ETC) generates adenosine triphosphate (ATP), which serves as an energy source for numerous critical cellular activities. However, the ETC also generates deleterious reactive oxygen species (ROS) as a natural byproduct of oxidative phosphorylation. ROS are considered the major cause of aging because they damage proteins, lipids, and DNA by oxidation. We analyzed the chronological life span, growth phenotype, mitochondrial membrane potential (MMP), and intracellular ATP and mitochondrial superoxide levels of 33 single ETC component-deleted strains during the chronological aging process. Among the ETC mutant strains, 14 ($sdh1{\Delta}$, $sdh2{\Delta}$, $sdh4{\Delta}$, $cor1{\Delta}$, $cyt1{\Delta}$, $qcr7{\Delta}$, $qcr8{\Delta}$, $rip1{\Delta}$, $cox6{\Delta}$, $cox7{\Delta}$, $cox9{\Delta}$, $atp4{\Delta}$, $atp7{\Delta}$, and $atp17{\Delta}$) showed a significantly shorter life span. The deleted genes encode important elements of the ETC components succinate dehydrogenase (complex II) and cytochrome c oxidase (complex IV), and some of the deletions lead to structural instability of the membrane-$F_1F_0$-ATP synthase due to mutations in the stator stalk (complex V). These short-lived strains generated higher superoxide levels and produced lower ATP levels without alteration of MMP. In summary, ETC mutations decreased the life span of yeast due to impaired mitochondrial efficiency.

• Animal Systematics, Evolution and Diversity
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• v.24 no.1
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• pp.25-32
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• 2008

The Gold-spotted pond frog, Rana plancyi chosenica, designated as a vulnerable species by IUCN Red list. This species is a typical example facing local population threats and extinction due to human activities in South Korea. A strategic conservation plan for this endangered species is urgently needed. In order to provide information for future conservation planning, accurate information on the genetic diversity and taxonomic status is needed for the establishment of conservation units for this species. In this study, we used a molecular genetic approach using the mitochondrial cytochrome b gene and control region sequences to find the genetic diversity of gold-spotted pond frogs within South Korea. We sequenced the mitochondrial DNA cytochrome b gene and control region of 77 individuals from 11 populations in South Korea, and one from Chongqing, China. A total of 15 cytochrome b gene haplotypes and 34 control region haplotypes were identified from Korean gold-spotted pond frogs. Mean sequence diversity among Korean gold-spotted pond frogs was 0.31% (0.0-0.8%) and 0.51% (0.0-1.0%), respectively. Most Korean populations had at least one unique haplotype for each locus. The Taean, Ansan and Cheongwon populations had no haplotypes shared with other populations. There was a sequence divergence between Korean and Chinese gold-spotted pond frogs (1.3% for cyt b; 2.9% for control region). Analysis of genetic distances and phylogenetic trees based on both cytochrome b and control region sequences indicate that the Korean gold-spotted pond frog are genetically differentiated from those in China.

• International Journal of Industrial Entomology and Biomaterials
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• v.44 no.2
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• pp.65-71
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• 2022

The wild silkmoth Antheraea yamamai Guérin-Méneville, 1861 (Lepidoptera: Saturniidae) is an important producer of silk that is superior to the silk produced by traditional domesticated silkworm. In this study, we sequenced the complete mitochondrial genome (mitogenome) of An. yamamai collected from Jeju Island, which is the southernmost island approximately 100 km offshore southward from the Korean Peninsula. Determining this sequence will be necessary for tracing the biogeographic history of the species and developing molecular markers for identifying the origin of commercial products. Comparison of the sequence divergence among two available and the current mitogenomes revealed a low but substantial number of substitutions, totaling 23 nucleotides in the whole genome. CytB and ND5 showed the highest variability with five and four variations, respectively, suggesting that these regions will be prior regions to target for subsequent biogeographic and diagnosis study. Phylogenetic reconstruction based on all available sequences of Saturniidae showed that An. yamamai is a sister to the congeneric species An. pernyi, corroborating that Antheraea is a highly supported monophyletic group. The tribe Saturniini was clearly non-monophyletic and interrupted by Attacini and Bunaeini.