• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2004년도 International Meeting of the Microbiological Society of Korea
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• pp.71-72
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• 2004

• Plant Biotechnology Reports
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• 제3권4호
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• pp.267-275
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• 2009

Over the years, cyanobacteria have been regarded as ideal model systems for studying fundamental biochemical processes like oxygenic photosynthesis and carbon and nitrogen assimilation. Additionally, they have been used as human foods, sources for vitamins, proteins, fine chemicals, and bioactive compounds. Aiming to increase plant productivity as well as nutritional values, cyanobacterial genes involved in carbon metabolism, fatty acid biosynthesis, and pigment biosynthesis have been intensively exploited as alternatives to homologous gene sources. In this short review, transgenic plants with cyanobacterial genes generated over the last two decades are examined, and the future prospects for transgenic crops using cyanobacterial genes obtained from functional genomics studies of numerous cyanobacterial genomes information are discussed.

• Biomolecules & Therapeutics
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• 제10권4호
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• pp.211-217
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• 2002

Hepatoprotective activity of methanol extract of Angelica tenuissima Nakai on the $CCl_4$-induced hepatotoxicity was investigated. To elucidate the hepatoprotective activity and free radical scavenging effect, we examined alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin, total protein, cholesterol, malondialdehyde (MDA) levels in serum and activities of superoxide dismutase (SOD), catalase (CAT) in hepatic tissue as compared with those of carbon tetrachloride-induced rats. The action mechanism also has been estimated by quantative analysis of cytochrome P450 (CYP), NADPH-CYP reductase for phase I metabolism and glutathion (GSH), glutathion S-transferase (GST) level for phase II metabolsim. Treatment of Angelica tenuissima methanol extract significantly lowered the levels of alanine aminotransferase and aspartate aminotransferase. In addition, the levels of cholesterol, triglyceride, MDA, CAT were decreased, and SOD was activated. This result indicates that the hepatoprotective effect of Angelica tenuissima methanol extract on the CCl4-induced hepatotoxicity would be originated from reduction of the NADPH-CYP reductase, GSH and the enhancement of the activities of GST, CYP.

• Biotechnology and Bioprocess Engineering:BBE
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• 제10권5호
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• pp.451-461
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• 2005

The effect of carbon dioxide on yeast growth was investigated during the cultivation of pH 5.0 and pH 6.8. by replacing the nitrogen part with carbon dioxide under aerobic conditions. The values of the specific growth rate under pH 5.0 and pH 6.8 conditions became 64.0% and 46.9%, respectively, compared to those before the change in gas composition. This suggests that the effect of carton dioxide was greater pronounced in pH 6.8 than in pH 5.0. The genome-wide transcriptional response to elevated carbon dioxide was examined using a DNA microarray. As for upregulated genes, it was noteworthy that 3 genes were induced upon entry into a stationary phase and 6 genes were involved in stress response. Of 53 downregulated genes, 22 genes were involved in the ribosomal biogenesis and assembly and 5 genes were involved in the lipid metabolism. These facts suggest that carbon dioxide could bring the cell conditions partially to a stationary phase. The ALD6 gene encoding for cytosolic acetaldehyde dehydrogenase was downregulated, which would lead to a lack of cell components for the growth. The downregulation of ALD6 was greater in pH 6.8 than in pH 5.0. consistent with physiological response. This suggests that it might be the most effective factor for growth inhibition.

• Journal of Microbiology and Biotechnology
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• 제4권2호
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• pp.146-150
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• 1994

Production of poly-$\beta$-hydroxybutyrate (PHB) in fed-batch fermentation was studied. Utilization of carbon for PHB biosynthesis was investigated by using feeding solutions with different ratios of carbon to nitrogen (C/N). It was observed that at a high C/N ratio carbon source was more preferably utilized for PHB accumulation while its consumption for cellular metabolism appeared to be more favored at a low C/N value. A high cell concentration (184 g/l) was achieved when ammonium hydroxide solution was fed to control the pH, which was also utilized as the sole nitrogen source. For the mass production of PHB, two-stage fed-batch operations were carried out where PHB accumulation was observed to be stimulated by switching the ammonium feeding mode to the nitrogen limiting condition. A large amount of PHB (108 g/l) was obtained with cellular content of 80% within 50 hrs of operation.

• 미생물학회지
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• 제20권4호
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• pp.161-172
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• 1982

In order to compare the metabolic activities of methanol utilizing bacteria, Pseudomonas sp. grown in different carbon sources, changes in respiratory activities, prinicipal enzyme activities for the energy metabolism, and the macromolecular compositions of the cells grown on methanol or glucose were measured. 1. The respiratory activity of cells grown on methanol was higher than that of cells grown on glucose, while glucose exhibited the highest $O_2-consumption$ rate among the different respiratory substrates. 2. TRhe activity of hydroxy pyruvate reductase which participates in serine pathway was high in the cells grown on methanol. However, activities of NAD-linked alcohol dehydrogenase, formaldehyde dehydrogenase and formate dehydrogenase were slightly lower in the cells grown on glucose thant on methanol. 4. For succinic dehydrogenase and malic dehydrogenase which take part in TCA cycle, the specific activities were higher in the cells grown on methanol than in those grown on glucose. No activity of glucose-6-phosphate dehydrogenase, which participates in pentose monophosphate shunt, was detectable in the cells grown on either carbon sources. 5. Protein contents of the cells grown on methanol increased relatively compared with those of the cells grown on glucose. However, there are no changes in the contents of carbohydrate and nucleic acid.

• 한국임상약학회지
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• 제14권1호
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• pp.32-35
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• 2004

The purpose of this study was to investigate the pharmacokinetic changes of verapamil in rabbits with hepatic disorder induced by carbon tetrachloride. The plasma concentrations of verapamil were increased significantly (p<0.05, in slight group; P<0.01, in moderate and severe group) in all groups of hepatic disorder compared to the control group. Morover, the $C_{max}\;in\;slight\;(77.9\%$ increase), moderate ($110\%$ increase), and severe ($174\%$ increase) hepatic disorder groups were significantly (p<0.05, in slight; p<0.01, in moderate and severe) higher than that in control rabbits. These resulted in significantly (p<0.05, in slight; p<0.01, in moderate and severe) greater area under the plasma concentration-time curve (AUC) in moderate ($49.8\%$ increase), moderate ($95.0\%$ increase), and severe ($144\%$ increase) hepatic disorder groups than that in control rabbits. Hence, the relative bioavailability values were 149, 195, and $244\%$ for slight, moderate, and severe hepatic disorder groups, respectively. This could be due to decrease in metabolism of verapamil in the liver because of suppressed hepatic function in the hepatic disorder groups because verapamil is mainly metabolized in the liver.

• BMB Reports
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• 제46권12호
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• pp.575-581
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• 2013

Lipid droplet (LD) is a cellular organelle that stores neutral lipids as a source of energy and carbon. However, recent research has emerged that the organelle is involved in lipid synthesis, transportation, and metabolism, as well as mediating cellular protein storage and degradation. With the exception of multi-cellular organisms, some unicellular microorganisms have been observed to contain LDs. The organelle has been isolated and characterized from numerous organisms. Triacylglycerol (TAG) accumulation in LDs can be in excess of 50% of the dry weight in some microorganisms, and a maximum of 87% in some instances. These microorganisms include eukaryotes such as yeast and green algae as well as prokaryotes such as bacteria. Some organisms obtain carbon from $CO_2$ via photosynthesis, while the majority utilizes carbon from various types of biomass. Therefore, high TAG content generated by utilizing waste or cheap biomass, coupled with an efficient conversion rate, present these organisms as bio-tech 'factories' to produce biodiesel. This review summarizes LD research in these organisms and provides useful information for further LD biological research and microorganism biodiesel development.

• Journal of Plant Biotechnology
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• 제37권2호
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• pp.205-211
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• 2010

Yield productivity of staple crops must be increased at least 50% by 2050, in order to feed the world population which is expected to reach 90 billions. Photosynthetic carbon assimilation and carbohydrate metabolism leading to the production of starch would be the final frontier to quest for new sources of technology enabling such a drastic increase of crop productivity. In this review, attempts to genetically engineer plant photosynthetic carbon reduction cycle and metabolic pathways to increase starch production are introduced.

• Journal of Microbiology and Biotechnology
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• 제9권4호
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• pp.404-413
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• 1999

Methanopyrus kandleri is a hyperthermophilic methanogen that represents one of the most heat-resistant organisms: the maximum growth temperature of M. kandleri is $110^{\circ}C$. A random sequence analysis of the genomic DNA of M. kandleri has been performed to obtain genomic information. More than 200 unique sequence tags were obtained and compared with the sequences in the GenBank and PIR databases. About 30% of the analyzed tags showed strong sequence similarity to previously identified genes involved in various cellular processes such as biosynthesis, transport, methanogenesis, or metabolism. When statistics relating to the frequency of codons were examined, the sequenced open reading frames showed highly biased codon usage and a high content of charged amino acids. Among the identified genes, a homologue of the catalytic subunit of carbon monoxide dehydrogenase (CODH) that reduces $CO_2$ to CO was cloned and sequenced in order to examine its detailed gene structure. The cloned gene includes consensus promoters. The amino acid sequence of the cloned gene shows a strong homology with the CODH genes from methanogenic Archaea, especially in the presumed binding sites for Fe-S centers.