• Asian-Australasian Journal of Animal Sciences
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• v.20 no.5
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• pp.768-774
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• 2007

To study the effect of dietary docosahexaenoic acid (DHA) enrichment on the expression of hepatic genes in pigs, weaned, crossbred pigs (30 d old) were fed diets supplemented with either 2% tallow or DHA oil for 18 d. Hepatic mRNA was extracted. Suppression subtractive hybridization was used to explore the hepatic genes that were specifically regulated by dietary DHA enrichment. After subtraction, we observed 288 cDNA fragments differentially expressed in livers from pigs fed either 2% DHA oil or 2% tallow for 18 d. After differential screening, 7 genes were found to be differentially expressed. Serum amyloid A protein 2 (SAA2) was further investigated because of its role in lipid metabolism. Northern analysis indicated that hepatic SAA2 was upregulated by dietary DHA enrichment (p<0.05). In a second experiment, feeding 10% DHA oil for 2d significantly increased the expression of SAA2 (compared to the 10% tallow group; p<0.05). The porcine SAA2 full length cDNA sequence was cloned and the sequence was compared to the human and mouse sequences. The homology of the SAA2 amino acid sequence between pig and human was 73% and between pig and mouse was 62%. There was a considerable difference in SAA2 sequences among these species. Of particular note was a deletion of 8 amino acids, in the pig compared to the human. This fragment is a specific characteristic for the SAA subtype that involved in acute inflammation reaction. Similar to human and mouse, porcine SAA2 was highly expressed in the liver of pigs. It was not detectable in the skeletal muscle, heart muscle, spleen, kidney, lung, and adipose tissue. These data suggest that SAA2 may be involved in mediation of the function of dietary DHA in the liver of the pig, however, the mechanism is not yet clear.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2000.04a
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• pp.157-167
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• 2000

A thermostable chitosanase gene from the isolated strain, Bacillus sp. CK4, was cloned, and its complete DNA sequence was determined. The thermostable chitosanase gene was composed of an 822-bp open reading frame which encodes a protein of 242 amino acids and a signal peptide corresponding to a 30 kDa enzyme in size. The deduced amino acid sequence of the chitosanase from Bacillus sp. CK4 exhibits 76.6%, 15.3%, and 14.2% similarities to those from Bacillus subtilis, Bacillus ehemensis, and Bacillus circulans, respectively. C-terminal homology analysis shows that Bacillus sp. CK4 belongs to the Cluster III group with Bacillus subtilis. The size of the gene was similar to that of a mesophile, Bacillus subtilis showing a higher preference for codons ending in G or C. The functional importance of a conserved region in a novel chitosanase from Bacillus sp. CK4 was investigated. Each of the three carboxylic amino acid residues were changed to E50D/Q, E62D/Q, and D66N/E by site-directed mutagenesis. The D66N/E mutants enzymes had remarkably decreased kinetic parameters such as $V_{max}$ and k$\sub$cat/, indicating that the Asp-66 residue was essential for catalysis. The thermostable chitosanase contains three cysteine residues at position 49, 72, and 211. Titration of the Cys residues with DTNB showed that none of them were involved in disulfide bond. The C49S and C72S mutant enzymes were as stable to thermal inactivation and denaturating agents as the wild-type enzyme. However the half-life of the C211S mutant enzyme was less than 60 min at 80$^{\circ}C$, while that of the wild type enzyme was about 90 min. Moreover, the residual activity of C211S was substantially decreased by 8 M urea, and fully lost catalytic activity by 40% ethanol. These results show that the substitution of Cys with Ser at position 211 seems to affect the conformational stability of the chitosanase.

• Journal of Microbiology and Biotechnology
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• v.17 no.7
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• pp.1106-1112
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• 2007

This report provides the complete nucleotide sequences of the full-length cDNA encoding squalene synthase (SQS) and its genomic DNA sequence from a triterpene-producing fungus, Ganoderma lucidum. The cDNA of the squalene synthase (SQS) (GenBank Accession Number: DQ494674) was found to contain an open reading frame (ORF) of 1,404 bp encoding a 468-amino-acid polypeptide, whereas the SQS genomic DNA sequence (GenBank Accession Number: DQ494675) consisted of 1,984 bp and contained four exons and three introns. Only one gene copy was present in the G. lucidum genome. The deduced amino acid sequence of Ganoderma lucidum squalene synthase (GI-SQS) exhibited a high homology with other fungal squalene synthase genes and contained six conserved domains. A phylogenetic analysis revealed that G. lucidum SQS belonged to the fungi SQS group, and was more closely related to the SQS of U. maydis than to those of other fungi. A gene expression analysis showed that the expression level was relatively low in mycelia incubated for 12 days, increased after 14 to 20 days of incubation, and reached a relatively high level in the mushroom primordia. Functional complementation of GI-SQS in a SQS-deficient strain of Saccharomyces cerevisiae confirmed that the cloned cDNA encoded a squalene synthase.

• Journal of Aquaculture
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• v.7 no.1
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• pp.41-54
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• 1994

In order to evaluate the availability of lacZ as a reporter gene for producing transgenic mud loach, foreign DNA, bacterial \beta-galactosidase$ gene (lacZ) was microinjected into mud loach eggs and its insertion and expression were examined. X-gal based histochemical assay, fluorimetric analysis of \beta-galactosidase$ with 4-methylumbelliferyl-$\beta$-D-galactoside (MUG) and molecular biological examination using polymerase chain reaction (PCR), dot blot, southern blot and sequence analysis of PCR products were carried out to analyze both microinjected group and non-injected controls. The results are disccussed in this paper.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.6
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• pp.758-763
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• 2012

As a member of a subclass of immunophilins, it is controversial that FKBP38 acts an upstream regulator of mTOR signaling pathway, which control the process of cell-growth, proliferation and differentiation. In order to explore the relationship between FKBP38 and mTOR in the Cashmere goat (Capra hircus) cells, a full-length cDNA was cloned (GenBank accession number JF714970) and expression pattern was analyzed. The cloned FKBP38 gene is 1,248 bp in length, containing an open reading frame (ORF) from nucleotide 13 to 1,248 which encodes 411 amino acids, and 12 nucleotides in front of the initiation codon. The full cDNA sequence shares 98% identity with cattle, 94% with horse and 90% with human. The putative amino acid sequence shows the higher homology which is 98%, 97% and 94%, correspondingly. The bioinformatics analysis showed that FKBP38 contained a FKBP_C domain, two TPR domains and a TM domain. Psite analysis suggested that the ORF encoding protein contained a leucine-zipper pattern and a Prenyl group binding site (CAAX box). Tissue-specific expression analysis was performed by semi-quantitative RT-PCR and showed that the FKBP38 expression was detected in all the tested tissues and the highest level of mRNA accumulation was detected in testis, suggesting that FKBP38 plays an important role in goat cells.

• Ocean and Polar Research
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• v.25 no.4
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• pp.607-615
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• 2003

Many organisms are known to survive in icy environments. These include both over wintering terrestrial insects and plants as well the marine fish inhabiting high latitudes. The adaptation of these organisms is both a fascinating and important topic in biology. Marine teleosts in particular, can encounter ice-laden seawater that is approximately $1^{\circ}C$ colder than the colligative freezing point of their body fluids. These animals produce a unique group of proteins, the antifreeze proteins (AFPs) or antifreeze glycoproteins (AFGPs) that absorb the ice nuclei and prevent ice crystal growth. Presently, there are at least four different AFP types and one AFGP type that are isolated from a wide variety of fish. Despite their functional similarity, there is no apparent common protein homology or ice-binding motifs among these proteins, except that the surface-surface complementarity between the protein and ice are important for binding. The remarkable diversity of these proteins and their odd phylogenetic distribution would suggest that these proteins might have evolved recently in response to sea level glaciations just 1-2 million years ago in the northern hemisphere and 10-30 million years ago around Antarctica. Winter flounder, Pleuronectes americanus, has been used as a popular model to study the regulation of AFP gene expression. It has a built-in annual cycle of AFP expression controlled negatively by the growth hormone. The signal transduction pathways, transcription factors and promoter elements involved in this process have been studied in our laboratory and these studies will be presented.

• Journal of the Korean Mathematical Society
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• v.46 no.2
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• pp.363-447
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• 2009

The author previously defined the spectral invariants, denoted by $\rho(H;\;a)$, of a Hamiltonian function H as the mini-max value of the action functional ${\cal{A}}_H$ over the Novikov Floer cycles in the Floer homology class dual to the quantum cohomology class a. The spectrality axiom of the invariant $\rho(H;\;a)$ states that the mini-max value is a critical value of the action functional ${\cal{A}}_H$. The main purpose of the present paper is to prove this axiom for nondegenerate Hamiltonian functions in irrational symplectic manifolds (M, $\omega$). We also prove that the spectral invariant function ${\rho}_a$ : $H\;{\mapsto}\;\rho(H;\;a)$ can be pushed down to a continuous function defined on the universal (${\acute{e}}tale$) covering space $\widetilde{HAM}$(M, $\omega$) of the group Ham((M, $\omega$) of Hamiltonian diffeomorphisms on general (M, $\omega$). For a certain generic homotopy, which we call a Cerf homotopy ${\cal{H}}\;=\;\{H^s\}_{0{\leq}s{\leq}1}$ of Hamiltonians, the function ${\rho}_a\;{\circ}\;{\cal{H}}$ : $s\;{\mapsto}\;{\rho}(H^s;\;a)$ is piecewise smooth away from a countable subset of [0, 1] for each non-zero quantum cohomology class a. The proof of this nondegenerate spectrality relies on several new ingredients in the chain level Floer theory, which have their own independent interest: a structure theorem on the Cerf bifurcation diagram of the critical values of the action functionals associated to a generic one-parameter family of Hamiltonian functions, a general structure theorem and the handle sliding lemma of Novikov Floer cycles over such a family and a family version of new transversality statements involving the Floer chain map, and many others. We call this chain level Floer theory as a whole the Floer mini-max theory.

• Journal of Microbiology
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• v.43 no.3
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• pp.313-318
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• 2005

In this study, we demonstrate the use of a PCR-based method for the detection of the specific genes involved in natural-product biosynthesis. This method was applied, using specifically designed PCR primers, to the amplification of a gene segment encoding for sedo-heptulose 7-phosphate cyclase, which appears to be involved in the biosynthetic pathways of $C_7N$ aminoacyclitol or its keto analogue-containing metabolites, in a variety of actinomycetes species. The sequences of DNA fragments (about 540 bp) obtained from three out of 39 actinomycete strains exhibited a high degree of homology with the sedo-heptulose 7-phosphate cyclase gene, which has been implicated in acarbose biosynthesis. The selective cultivation conditions of this experiment induced the expression of these loci, indicating that the range of $C_7N$ aminoacyclitol or its keto analogue-group natural products might be far greater than was previously imagined. Considering that a total of approximately 20 $C_7N$ aminoacyclitol metabolites, or its keto analogue-containing metabolites, have been described to date, it appears likely that some of the unknown loci described herein might constitute new classes of $C_7N$ aminoacyclitol, or of its keto analogue-containing metabolites. As these metabolites, some of which contain valienamine, are among the most potent antidiabetic agents thus far discovered, the molecular detection of specific metabolite-producing actinomycetes may prove a crucial step in current attempts to expand the scope and diversity of natural-product discovery.

• Journal of the Korea Organic Resources Recycling Association
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• v.17 no.4
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• pp.48-58
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• 2009

Glycosyl hydrolases (GH, EC 3.2.1.-) are key enzymes which can hydrolyze the glycosidic bonds between two or more carbohydrates, or between a carbohydrate and a non-carbohydrate moiety. The new enzyme nomenclature of glycoside hydrolases is based on their amino acid sequence similarity and structural features. Here, we examined the glycosyl hydrolase family(GHF) genes reported from earthworm species. Among overall 115 GHFs, 12 GHFs could be identified from earthworm species through CAZy database. Of 12 GHF group genes, five genes including GHF2, 5, 17, 18, 20 are thought to be potent for industrial applications. The alignment of these genes with same genes from other animal species exhibited high sequence homology and some important amino acid residues necessary for enzyme activity appeared to be conserved. These genes can be utilized as a pest control agent or applicable to the food industry, clinical therapeutics and organic wastes disposition.

• The Journal of Korean Society of Virology
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• v.29 no.2
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• pp.75-86
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• 1999

Rotaviruses belong to Reoviridae causes diarrhea in human beings as well as domestic animals. This study was conducted to see what type of human rotaviruses are distributed in Seoul and Kyung-gi province. Twenty two of 81 patients showed rotavirus positive with diagnostic kit and RNA electropherosis. We isolated all of rotaviruses from the patients. Electropherotypes of 22 isolates showed 4:2:3:2 pattern whereas those migration patterns were long type. All of those isolates belonged to group A. Twenty out of 22 isolates reacted with monoclonal antibodies specific to G1, P1A and subgroup II, whereas rest of them, A-29 and K-30 reacted with subgroup I specific monoclonal antibody. The nucleotide sequence of an isolate K-21 showed $98{\sim}100%$ and $90{\sim}96%$ homologies with those of Wa and KU strain, respectively.