• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.4
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• pp.367-371
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• 1992

In the present study, the effects of onion and garlic on copper and 1, 10-phenanthroline com plex induced DNA degradation were investigated by the decreased level of thiobarbiturin acid (TBA) reactive materials. Phenanthroline is specific for copper and the reaction releases TBA reactive material from DNA which can be measured by absorbance at 535nm. The levels of TBA reactive materials were decreased by adding onion or garlic ghomogenate into reaction mixture but the onion had more strong potency and the effect of onion was not changed by boiliing. Superoxide dismutase (SOD) and catalase have no inhibitory effects on copper induced DNa damage but reduced glutathone was more effective. The activities of antioxidant enzymes and the contents of sulfhydryl groups in onion and garlic were also investigated. The activity of SOD was more higher in garlic, but catalase and glutathione peroxidase activities were higher in onion. The contents of induced DNA damage were not by antioxidant enzymes such as SOD, catalase and glutathione peroxidase or sulfhydryl groups, but a substance which is more stable in high temperature.

• Journal of Microbiology
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• v.43 no.6
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• pp.569-571
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• 2005

White-rot fungi have the following enzyme systems for lignin degradation: laccase, lignin peroxidase and manganese peroxidase. There are other types of peroxidases related to lignin degradation, one of which we have cloned a cDNA gene of manganese-repressed peroxidase (MrP) in Trametes versicolor isolated in South Korea. The mrp transcript level has been decreased by $1{\mu}M\;of\;Mn^{2+}$.

• Biomedical Science Letters
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• v.24 no.4
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• pp.292-304
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• 2018

Microbes is becoming increasingly forensic possibility as a consequence of advances in massive parallel sequencing (MPS) and bioinformatics. Human DNA typing is the best identifier, but it is not always possible to extract a full DNA profile namely its degradation and low copy number, and it may have limitations for identical twins. To overcome these unsatisfactory limitations, forensic potential for bacteria found in evidence could be used to differentiate individuals. Prokaryotic cells have a cell wall that better protects the bacterial nucleoid compared to the cell membrane of eukaryotic cells. Humans have an extremely diverse microbiome that may prove useful in determining human identity and may even be possible to link the microbes to the person responsible for them. Microbial composition within the human microbiome varies across individuals. Therefore, MPS of human microbiome could be used to identify biological samples from the different individuals, specifically for twins and other cases where standard DNA typing doses not provide satisfactory results due to degradation of human DNA. Microbial forensics is a new discipline combining forensic science and microbiology, which can not to replace current STR analysis methods used for human identification but to be complementary. Among the fields of microbial forensics, this paper will briefly describe information on the current status of microbiome research such as metagenomic code, salivary microbiome, pubic hair microbiome, microbes as indicators of body fluids, soils microbes as forensic indicator, and review microbial forensics as the feasibility of microbiome-based human identification.

• Korean Journal of Environmental Biology
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• v.22 no.2
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• pp.265-272
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• 2004

Biological characteristics of anodic electrolyzed water were investigated in this study. Linear DNAs which were incubated at $4^\circ{C}$ and $25^\circ{C}$ for 10 mins in the anodic electrolyzed water were degraded about 40% and 50%, respectively. But the DNA was amplified pretty well without any degradation through polymerase chain reaction in the presence of anodic electrolyzed water. Protein degradation hardly occurred in the distilled water during entire incubation time of 7 days, while protein began to be degraded from 4 days in the anodic electrolyzed water. Rice seeds could germinate in the distilled water and anodic electrolyzed water with the same germination ratio, however, the anodic electrolyzed water inhibited the growth of roots and total length of rice seedlings in the soil. Anodic electrolyzed water did not affect the growth curve and cell number of marine alga significantly. The anodic electrolyzed water inhibited the browning of potato by inactivating 50% of polyphenol oxidase activity.

• Korean Journal of Microbiology
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• v.25 no.2
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• pp.103-109
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• 1987

An ozone-sensitive mutant of Escherichia coli strain B, MQ 1844 is described. Its properties, including high sensitivity to ozone and radiation, inducible filamentation, extensive DNA degradation and impaired DNA synthesis following ozonation, are attributable to a mutation in ozrB, a gene which is cotransducible with malB. Based on differences in phenotypic expression as well as on the particular location of this gene on the bacterial chromosome, ozrB appears as distinct from the other ozone-or radiation-sensitivity genes previously described.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.28-30
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• 2005

Because of high population diversity in soil microbial communities, it is difficult to accurately assess the capability of biodegradation of toxicant by microbes in soil and sediment. Identifying biodegradative microorganisms is an important step in designing and analyzing soil bioremediation. To remove non-important noise information, it is necessary to selectively enrich genomes of biodegradative microorganisms fromnon-biodegradative populations. For this purpose, a stable isotope probing (SIP) technique was applied in selectively harvesting the genomes of biphenyl-utilizing bacteria from soil microbial communities. Since many biphenyl-using microorganisms are responsible for aerobic PCB degradation In soil and sediments, biphenyl-utilizing bacteria were chosen as the target organisms. In soil microcosms, 13C-biphenyl was added as a selective carbon source for biphenyl users, According to $13C-CO_2$ analysis by GC-MS, 13C-biphenyl mineralization was detected after a 7-day of incubation. The heavy portion of DNA(13C-DNA) was separated from the light portion of DNA (12C-DNA) using equilibrium density gradient ultracentrifuge. Bacterial community structure in the 13C-DNAsample was analyzed by t-RFLP (terminal restriction fragment length polymorphism) method. The t-RFLP result demonstates that the use of SIP efficiently and selectively enriched the genomes of biphenyl degrading bacteria from non-degradative microbes. Furthermore, the bacterial diversity of biphenyl degrading populations was small enough for environmental genomes tools (metagenomics and DNA microarrays) to be used to detect functional (biphenyl degradation) genes from soil microbial communities, which may provide a significant progress in assessing microbial capability of PCB bioremediation in soil and groundwater.

• The Korean Journal of Zoology
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• v.14 no.4
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• pp.199-204
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• 1971

The effect of 400 R total-body X-irradiation on the rate of deoxycytidine-2-$^14 C$(CdR-2-$^14 C$) into DNA and on the degradation of DNA has been studied in the liver, spleen and thymus of the rat. The postirradiation period can be divided into a radiation reaction period followed by a regeneration period. During the period of radiation reaction, which consists of days 1-2, markdely decreased CdR-2-$^14 C$ incorporation into DNA of each organ is observed. Rate of incorporation of labeled precursor in the thymus shows the most profound decrease, whereas those in the liver and spleen show similar decrease when expressed as percent of normal. The change in the amount of DNA as percent of normal exhibits a similar pattern in all organs, but the rate of decrease is larger in the spleen and thymus compared to that in the liver. The period of regeneration as judged by the incorporation experiment appears day 4 to 5, which consists of the second phase of the regeneration period. The second phase is highlighted by a markedly increased rate of CdR-2-$^14 C$ incorporation and by a slow and continued increase in the amount of DNA in all organs. The regeneration occurs faster in the liver and spleen than in the thymus which is the most radiosensitive of the all. The findings of the present experiments are strongly suggestive of the fact that the radiation-induced loss of spleen and thymus DNA as well as the radiation-caused inhibition in the CdR incorporation into DNA of the thymus are the important factors in the elevated levels of CdR in the urine and plasma.

• Journal of Life Science
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• v.14 no.3
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• pp.406-410
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• 2004

Glyoxal or methylglyoxal was incubated with catalase in 0.24 M sodium phosphate buffer (pH 7.4) at 37$^{\circ}C$. Dicarbonyls modify and inactivate catalase. Plasmid DNA that is directly incubated with glycation propagators, glyoxal and methylglyoxal, showed different DNA mobility shift compared to nomal plasmid DNA. When plasmid DNA is added in Fenton reaction with glycated catalase, plasmid DNA was significantly strand broken and 8-hydroxydeoxyguanosine production was time dependently increased. These results suggest that glycation of antioxidant is synergistic effect to oxidative stress.

• Microbiology and Biotechnology Letters
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• v.40 no.4
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• pp.348-355
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• 2012

In the present study, we investigated the overexpression and characterization of bovine pancreatic (bp)- DNase I in Saccharomyces cerevisiae and Pichia pastoris. The bp-DNase I gene was fused in frame with the GAL10 promoter, $MF{\alpha}$, and GAL7 terminator sequences, resulting in the plasmid, pGAL-$MF{\alpha}$-DNaseI (6.4 kb). Also, the bp-DNase I gene was fused in frame with the AOX1 promoter, $MF{\alpha}$, and AOX1 terminator sequences, resulting in the plasmid, pPEXI (8.8 kb). The recombinant plasmids, pGAL-$MF{\alpha}$-DNaseI and pPEXI were introduced into S. cerevisiae and P. pastoris host cells, respectively. When the transformed yeast cells were cultured at $30^{\circ}C$ for 48 h in galactose or methanol medium, bp-DNase I was overexpressed and the most of activity was found in the extracellular fraction. P. pastoris transformant activity showed 45.5 unit/mL in the culture medium at 48 h cultivation, whereas S. cerevisiae transformant revealed 37.7 unit/mL in the extracellular fraction at 48 h cultivation. The enzymatic characteristics, such as DNA cleavage and half life were investigated. Treatment of the recombinant DNase I from P. pastoris induced degradation of the calf thymus DNA within 1 minute, and this DNA degradation rate was higher than that of commercial bp-DNase I (SIGMA) and the recombinant DNase I from S. cerevisiae.

• Korean Journal of Environmental Biology
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• v.18 no.2
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• pp.205-213
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• 2000

Laboratory studies have revealed that naturally transformable bacteria develop competence under in situ conditions. Thus, the occurrence of competent bacteria in the environment can be considered as a certainty The persistence of free DNA in natural habitats is influenced by nucleolytic degradation and protection from degradation by adsorption to minerals. Although DNA seeded into natural environment was hydrolysed at substantial rates, but was still detectable at low levels after even several weeks. Compared to the number of laboratory based studies, only a few data have been published dealing with transformation of bacteria in the field. Recently, the potential transfer of recombinant DNA (rDNA) from deliberately or accidentally released bacteria to indigenous microbes has raised biosafety issues, since the persistence of rDNA becomes independent of the survival of its original host and leads to unpredictable, long-term ecological effects. The aim of the present review is to summarise recent literature on horizontal gene transfer (HGT) by transformation among bacteria in both soil and aquatic habitat and special emphasis is placed on recent reports which have addressed HGT among bacteria in the field. [Transformation, Horizontal gene transfer (HGT), recombinant DNA (rDNA), Genetically modified microorganisms (GMMs), Biosafety]