• Journal of Microbiology and Biotechnology
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• v.10 no.4
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• pp.441-448
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• 2000

The production and cation flux-mediated activation of the P-type ATPase in Helicobacter pylori was investigated. Using the polymerase chain reaction (PCR), the proton pump genotype of H. pylori was found to be positive for both F-type and P-type ATPases. Yet, their production in terms of enzyme specific activity varied substantially depending on H. pylori strains, ranging over 3-fold. Its main constituent appeared to be the P-type ATPase pool, in contrast to other common bacterial compositions. Interestingly, the F-type ATPase was observed only when intact H. pyloricells were exposed to pH 4.5 or above (37$^{\circ}C$ for 1 h). In contrast, significant amounts of the P-type ATPase still remained after 1 h of cell treatment even at pH below 4.5. By enriching the acidic medium with RPMI(pH 3.0), the P-type ATPase was stabilized, accompained by inactivation of the F-type ATPase. Using H. pylori membrane vesicles, it was found that ammionia-mediated cation flux increased the rate of ATP hydrolysis by the P-type ATPase. Accordingly, these data strongly suggest that the P-type ATPase is involved or functions as an effective regulator for the cation flux across the H. pylori membrane, thereby reducing the risk of excess proton influx.

• Journal of Microbiology and Biotechnology
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• v.30 no.10
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• pp.1443-1457
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• 2020

The emergence and spread of antimicrobial resistance in pathogenic bacteria of fish and shellfish have caused serious concerns in the aquaculture industry, owing to the potential health risks to humans and animals. Among these bacteria, Aeromonas salmonicida, which is one of the most important primary pathogens in salmonids, is responsible for significant economic losses in the global aquaculture industry, especially in salmonid farming because of its severe infectivity and acquisition of antimicrobial resistance. Therefore, interest in the use of alternative approaches to prevent and control A. salmonicida infections has increased in recent years, and several applications of bacteriophages (phages) have provided promising results. For several decades, A. salmonicida and phages infecting this fish pathogen have been thoroughly investigated in various research areas including aquaculture. The general overview of phage usage to control bacterial diseases in aquaculture, including the general advantages of this strategy, has been clearly described in previous reviews. Therefore, this review specifically focuses on providing insights into the phages infecting A. salmonicida, from basic research to biotechnological application in aquaculture, as well as recent advances in the study of A. salmonicida.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1345-1348
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• 1999

The utility of a bioluminescence adenosine triphosphate(ATP) assay method for estimating bacterial levels in mackerel(Scomber japonicus) was investigated. Mackerel was stored at $1^{\circ}C$ throughout 10 days and its RLU(relative light unit) and APC(aerobic plate count) was determined. The ATP bioluminescence assay was validated during the storage of 32 samples, resulting in an agreement between the ATP assay and standard plate count methods of over 90% credibility. Therefore, ATP bioluminescence assay was considered as a rapid and near real-time means in estimating the microbial load on mackerel skin.

• Biomedical Science Letters
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• v.15 no.3
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• pp.257-260
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• 2009

Toll-like receptors (TLRs) recognize molecular structures derived from microbes including bacteria, viruses, yeast, and fungi. TLRs have emerged as a major signaling component of the mammalian host defense. TLR4 is a member of the Toll family that senses lipopolysaccharide (LPS), a cell wall component of gram negative bacteria. LPS recognition by TLR4 requires an additional accessory molecule, MD-2. LPS induces the activation of NF-${\kappa}B$ and IRF3 through MyD88 or TRIF-dependent pathways. The activation of NF-${\kappa}B$ leads to the induction of inflammatory gene products including cytokines and cyclooxygenase-2 (COX-2). This study was carried out to investigate the anti-inflammatory effects of oak wood vinegar. Oak wood vinegar inhibits the NF-${\kappa}B$ activation and COX-2 expression induced by LPS. These results provide new ideas to understand the mechanism of oak wood vinegar for its anti-bacterial and anti-inflammatory activities.

• Proceedings of the Microbiological Society of Korea Conference
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• 1991.04a
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• pp.237-242
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• 1991

In order to increase the production of glutathione by maximizing the expression of recombinant gsh plasmids, two genes responsible for the biosynthesis of glutathione were cloned. A gshI gene was cloned onto pBR322 plasmid as 3.6Kb PstI DNA fragment from E. coli K-12 chromosomal DNA. Also gshII gene was cloned onto pUC13 plasmid as 2.2Kb PstI-BamHI DNA fragment. In order to improve the glutathione producing activity more efficiently, various recombinant plasmids containing tandem repeated gshI genes or both genes in various copy number onto the same vector were constructed. E. coli cells harboring pGH501 plasmid (pUC8-gshI$\cdot$I$\cdot$II) showed the highest glutathione synthesizing activity. The conditions for glutathione production with an ATP-generating system such as acetate kinase reaction of E. coli cells or glycolytic pathway of yeast cells were examined using the E. coli cells harboring the pGH501 plasmid. When the acetate kinase reaction of E. coli cells was used as an ATP generating system, 20mM of L-csteine was converted into glutathione with a yield of $100\%$.

• Journal of Microbiology and Biotechnology
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• v.23 no.6
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• pp.750-758
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• 2013

Anthrax is a bacterial disease caused by the aerobic spore-forming bacterium Bacillus anthracis, which is an important pathogen owing to its ability to be used as a terror agent. B. anthracis spores can escape phagocytosis and initiate the germination process even in antimicrobial conditions, such as oxidative stress. To analyze the oxidative stress response in B. anthracis and thereby learn how to prevent antimicrobial resistance, we performed protein expression profiling of B. anthracis strain HY1 treated with 0.3 mM hydrogen peroxide using a comparative proteomics-based approach. The results showed a total of 60 differentially expressed proteins; among them, 17 showed differences in expression over time. We observed time-dependent changes in the production of metabolic and repair/protection signaling proteins. These results will be useful for uncovering the metabolic pathways and protection mechanisms of the oxidative response in B. anthracis.

• Korean Journal of Environmental Agriculture
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• v.39 no.3
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• pp.178-187
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• 2020

BACKGROUND: Spent coffee grounds are the most valuable resource for agriculture and industry. However, it is almost thrown untreated into landfills or incineration. Composting is an efficient process for converting spent coffee to fertilizer. METHODS AND RESULTS: Composting was conducted in the compost pile (40 ㎥) equipped with a forced aeration system. Physical and chemical properties containing temperature, pH, electrical conductivity, and moisture were measured through the composting period. Moreover, biological changes were examined for the composting phase using Illumina Miseq sequencing of the 16S rRNA gene. We found 7-14 phyla comprising 250-716 species from a variety phase of compost. During the composting period, Firmicutes were dominated, followed by Actinobacteria and Proteobacteria. CONCLUSION: The result indicated that the use of spent coffee improved the quality of organic fertilizer and changed the microbial communities, unique to the thermal composting stage, which could enhance the composting process. These findings suggest that spent coffee composted material can provide a significant amount of nutrients, thereby supporting plant growth.

• Korean Journal of Pharmacognosy
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• v.28 no.1
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• pp.35-41
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• 1997

Following ginsenoside-Rb1-hydrolyzing assay, strictly anaerobic bacteria were isolated from human feces and identified as Prevotella oris. The bacteria hydrolyzed ginsenoside Rb1 and Rd to $20-O-{\beta}-D-glucopyranosyl-20(S)-protopanaxadiol$ (I), ginsenoside Rb2 to $20-O-[{\alpha}-L-arabinofuranosyl (1{\rightarrow}6)-{\beta}-D-glucopyranosyl] - 20(S)-protopanaxadiol$ (ll) and ginsenoside Rc to $20-O-[{\alpha}-L-arabinofuranosyl (1{\rightarrow} 6){\beta}-D-g1ucopyranosyl]-20(S)-protopanaxadiol$ (III) like fecal microflora, but did not attack ginsenoside Re nor Rgl (Protopanaxatriol-type). Pharmacokinetic studies of ginseng saponins was also performed using specific pathogen free rats and demonstrated that the intestinal bacterial metabolites I-111, 20(S)- protopanaxatriol(IV) and 20(S)-protopanaxadiol(V) were absorbed from the intestines to $blood(0.4-5.1\;{\mu}g/ml)$ after oral administration with total saponin(1 g/kg/day).

• Journal of Periodontal and Implant Science
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• v.32 no.4
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• pp.745-752
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• 2002

Osteomyelitis is an exhaustive disease whose main feature is an inflammation of inner part of bone, bone marrow. In oral and maxillofacial area, we have maxillary and mandibular osteomyelitis and the latter is dominant because of its impaired blood supply. The main cause of osteomyelitis is a bacterial infection and the ways of infections are by periapical odontogenic infection, fracture, post-operative complication, and periodontal disease. The predominant etiologic factor is periapical odontogenic infection mostly caused by advanced dental caries. It is generally believed that periodontal disease could be a cause of osteomyelitis. But periodontal disease is usually confined to the alveolar bone area and not extends to the underlying bone marrow. Accordingly periodontal infection per se rarely cause produce oseomyelitis. Even though osteomyeltis could be occurred by periodontal disease, its virulence of infection is milder than periapical odontogenic infection. So it usually provokes sclerosing or hyperplastic osteomyelitis rather than suppurative type. We had a case of suppurative osteomyelitis caused by periodontal disease and treated it with periodontal and oral and maxillofacial surgical method.

• Proceedings of the Korea Crystallographic Association Conference
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• 2003.05a
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• pp.17-17
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• 2003

tRNA (m¹ G37) methyltransferase (TrmD) catalyze s the trans for of a methyl group from S-adenosyl-L-methionine (AdoMet) to G/sup 37/ within a subset of bacterial tRNA species, which have a residue G at 36th position. The modified guanosine is adjacent to and 3' of the anticodon and is essential for the maintenance of the correct reading frame during translation. We have determined the first crystal structure of TrmD from Haemophilus influenzae, as a binary complex with either AdoMet or S-adenosyl-L-homocysteine (AdoHcy), as a ternary complex with AdoHcy/phosphate, and as an apo form. The structure indicates that TrmD functions as a dimer (Figure 1). It also suggests the binding mode of G/sup 36/G/sup 37/ in the active site of TrmD and catalytic mechanism. The N-terminal domain has a trefoil knot, in which AdoMet or AdoHcy is bound in a novel, bent conformation. The C-terminal domain shows a structural similarity to DNA binding domain of trp or tot repressor. We propose a plausible model for the TrmD₂-tRNA₂ complex, which provides insights into recognition of the general tRNA structure by TrmD (Figure 2).