• Korean Journal of Environmental Agriculture
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• v.38 no.3
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• pp.197-204
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• 2019

BACKGROUND: Living modified microorganisms (LMMs) have been focused in two very different aspects of positive and negative effects on ecology and human health. As a model experiment, wild type and a foreign origin gene-harboring modified E. coli strains were subjected to comparison of their metabolomes and potential effects on soil microbiota in the laboratory sets. This study assumes the unintentional release of LMMs and tries to suggest potential effects on the soil microbiota even at minimal settings. METHODS AND RESULTS: Metabolomes from the wild type and LM E. coli were analyzed by NMR and the profiles were compared. In the laboratory soil experiments, the two types of E. coli were added to the soils and monitored for the bacterial community compositions. Those metabolomic profiles did not show significant differences. The microbial community structures from the time series soil DNAs for both the sets using wild type and LMO also did not indicate significant changes, but minor by the addition of foreign organisms regardless of wild or LMO. CONCLUSION: Even if the recombinant microorganism (LMO) is released into the soil environment, the survival of microorganisms in the environment would be one of the major factors for the transfers of foreign genes to other organisms and diffusion into the soil environment.

• The Korean Journal of Mycology
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• v.10 no.1
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• pp.27-31
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• 1982

The antibacterial activity of Poria cocos against the human pathogenic bacteria and general bacteria was observed. The results obtained were as follows; 1. There wasn't any anti­bacterial activity at the Poria cocos powders, pieces and its extracts in every different kinds and places of origin. 2. Hyphae of Poria cocos in every different kinds and places of origin had the antibacterial activity against four Gram positive bacteria, i.e., Staphylococcus aureus, S. epidermidis, Bacillus subtilis and Streptococcus faecalis, on the other hand, hadn't the antibacterial activity against six Gram negative bacteria, Salmonella typhi, Shigella dysenteriae, Pseudomonas aeruginosa, Escherichia coli, Proteus vulgaria and Klebsiella pneumoniae. 3. The average inhibitory zone was 13.6mm for S. aureus, 14.7mm for S. epidermidis, 12.7mm for B. subtilis, and 13.2mm for S. faecalis at the concentration of $335{\mu}g$ of hyphae of Poria cocos.

• Korean Journal of Plant Tissue Culture
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• v.28 no.4
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• pp.221-225
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• 2001

Some factors of wounding methods, solidifying agents, origin of leaf explants, cone. of acetosyring-one, and MES affecting regeneration and transformation by Agrobacterium tumefaciens were investigated to establish an efficient transformation system of apple. Wounding by cutting the leaves merely showed the tendency of regeneration and transformation with higher efficiency compared with that of wounding by non-traumatic forcep when carrying out co-cultivation for three days after bacterial inoculation. While examining the solidifying agents of medium with the combination of agar (A)＋Gelrit $e^{ }$ (G) in g. $L^{-1}$ , the higher concentration of Gelrit $e^{ }$ increased the efficiency of regeneration. However, there was no difference in the efficiency of transformation from the treatments of 2.5 G, 3.5 A+1.2 G, and 7.0 G. The origin of leaf explants showed no difference statistically in the efficiency of regeneration and transformation, but that from the shoots of proliferation medium showed the tendency with higher efficiency. The concentration of above 0.1 mM acetosyringon had an increase in the efficiency of regeneration and transformation and the concentration of 0.15 mM had the highest efficiency of transformation in the treatment of acetosyringone with different concentration. There was no effect of MES on regeneration and transformation.ion.

• Journal of Life Science
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• v.19 no.5
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• pp.684-687
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• 2009

Xanthomonas arboricola pv. pruni, the causal agent of bacterial shot holes in stone fruits, was known to have a low population diversity. To investigate the genetic characteristics of X. arboricola pv. pruni isolated in Korea, three strains which have identical 16S rDNA sequences - including type strain (LMG852), Japanese isolate (MAFF301420) and Korean isolate (XWD1) - were analysed based on the nucleotide sequences of three DNA regions and RAPD pattern. No sequence diversity among the three strains was found within the ITS, glnA and atpD gene sequences. However, five of 756 nucleotides of the atpD gene determined (accession number FJ429319) were different from those of the French strain available from the Genbank database. RAPD analyses performed with 40 different arbitrary primers revealed that two strains isolated from Korea and Japan showed similarity in their band patterns distinguished by type strain. These results suggest that Korean and Japanese strains are very close and belong to a population with a low genetic diversity, and might have a different origin from strains found in West Europe.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.22 no.4
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• pp.420-429
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• 2000

Oral & maxillofacial infections are most commonly odontogenic in origin. Although such infections are usually self-limiting, they may occasionally spread deeply into fascial spaces or planes far from the initial site of involvement. If early diagnosis and appropriate therapy is delayed, complications such as mediastinal extension, retropharyngeal spread and airway obstruction could happen to the patients. For the study of the microbiology, we have retrospectively analysed the oral & maxillofacial infected patients in the Dept. of Oral & Maxillofacial Surgery. In-Ha University Hospital from 1997 September to 2000 April. The results were as follows 1. The male patients were more common than female, with male 61.9% and female 38.1%. 2. Dental originated infections were most common cause with the incidence of 62%. 3. Most common fascial space involved was buccal space 42cases(37.2%) followed by submandibular space 13cases(11.5%), infraorbital space 13cases(11.5%), masseteric space 11cases(9.7%), periapical abscess 11cases(9.7%). 4. The causative organisms isolated from the pus culture were Gram Positive Bacterial species, which were 46cases(31.9%) of Streptococcus viridans, 16cases(8.6%) of ${\alpha}$ and ${\beta}-hemolytic$ streptococcus, 4cases(3.1%) of Strep.-group D non enterococci, 7cases(5.1%) of Staphylococcus Coa. neg., 5cases(3.9%) of Staphylococcus aureus, 3cases(2.3%) of Enterococcus faecalis, 1case(0.8%) of Bacillus species, 1case(0.8%) of Peptostreptococcus, 1case(0.8%) of Clostridium and Gram negative bacterial species, which were 4cases(3.1%) of Acinetobacter baumannii, 2cases(1.6%) of Pseudomonas aeruginosa, 2cases(1.6%) of Burkholderia cepacia, 1case(0.8%) of Neisseria species, 1case(0.8%) of Klebsiella pneumoniae, 1case(0.8%) of Klebsiella oxytoca, 1case(0.8%) of Escherichia coli. 5. In drug sensitivity test, high resistant tendency was found in Penicillin system(Penicillin G 83.3%, Ampicillin 60%) and Aminoglycosides (Gentamycin 50%, Tobramycin 45.5%), but tertiary Cephalosporin system(Cefoperazone 9.1%, Ceftazidime 18.2%), and glycopeptides system (Teicoplanin 0%, Vancomycin 0%) showed lower resistancy.

• Journal of the Mineralogical Society of Korea
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• v.24 no.2
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• pp.91-99
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• 2011

The turbidity in several wells of Samdong-myeon, Ulsan, exceeded potable groundwater standard (1 NTU). Mineralogical analysis showed that the fine suspended particles are ferrihydrite spheres with a size of less than $0.5\;{\mu}m$ and helical iron-oxidizing bacterial filaments, and their aggregates. Ferrihydrite was almost amorphous only showing two electron diffraction rings, and contained Si and P. Helical bacterial filaments were almost replaced by ferrihydrite. The helical bacteria have played an important role in the ferrihydrite formation by becoming the loci for ferrihydrite precipitation as well as oxidizing ferrous iron. The physicochemical conditions of low pH, low redox potential, high Ca concentration, and high alkalinity are consistent with the hydrogeochemical characteristics of carbonate groundwater, implicating that the inflow of deep ferriferous carbonate groundwater and its oxidation have caused the ferrihydrite turbidity in several wells of the study area.

• Korean Journal of Ecology and Environment
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• v.41 no.spc
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• pp.21-26
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• 2008

The in situ incubation experiment was carried out using $^{13}C$ tracer to determine primary productivity and fatty acid production rate in the shallow, eutrophic Shingu reservoir on 4th July. Particulate organic matter (POM) accounted for 76% in suspended particulate matter (SPM), and average concentration of chlorophyll-${\alpha}$ was $89{\mu}g\;L^{-1}$ in the euphotic layer. Total amount of chlorophyll-${\alpha}$ (Chl-${alpha}$), primary productivity and Chl-${alpha}$ specific productivity in euphotic layer were 112 mg Chl-${alpha}m^{-2}$, 3.53 g C $m^{-2}\;d^{-1}$, 32mg C mg Chl-${\alpha}^{-1}\;d^{-1}$, respectively. The fatty acid composition in newly produced organic matter and suspended organic matter didn't show any significant difference, demonstrating that autochthonous organic matter should be a major source of POM pool. In addition, the fatty acids of bacterial origin were increased through extracellular release of newly photosynthesized DOC, and closely coupled with bacterial assimilation. This result suggests that organic carbon should be actively cycled through the microbial loop in Shingu reservoir in summer.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.6
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• pp.586-592
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• 1986

The marine bacterial flora of seawater at Masan Bay located in southern part of Korea was investigated to provide basic information about the origin of red tides in this area. The samples were collected at 5 sampling stations (see fig.1) established once a month from July 1985 to June 1986. The results are summerized as follows: 1. Two hundred and ninety one strains of marine bacteria among 299 strains isolated were identified from 156 samples(150 seawater samples and 6 mud samples) collected in the study area. 2. During the study period, the dissolved oxygen ranged from 2.1 to 6.3 ml/l; temperature of surface seawater ranged from 4.6 to $30.1^{\circ}C$; phosphate, silicate and nitrite ranged from 1.6 to 5.6 ${mu}g-at/l$, 327.27 to 3798.38 ${mu}g-at/l$, and 1.09 to 5.5 ${mu}g-at/l$, respectively. 3. Pseudomonas spp. were the most dominant bacterial species before red tides, Ancinetobacter spp. and Flavobacterium spp. during red tides, and Flavobacterium spp., Vibrio spp. and Acinetobacter spp. after red tides. 4. Viable counts marine bacterial flora ranged $10^4{\sim}10^8cell/ml$, and the most abundant viable counts of marine bacteria occured during red tides ($10^7{\sim}10^8cell/ml$).

• International Journal of Industrial Entomology and Biomaterials
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• v.33 no.2
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• pp.85-91
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• 2016

Exosomes are homogenous vesicles of 40-100 nm diameter produced endogenously. Exosomes are generated by inward budding into multi-vesicular bodies (MVB) and then released to extracellular space. Exosomes contain various nucleic acid and protein cargoes from their cells of origin and this endosomal cellular molecules are used for intracellular communication and for both promotion and suppression of immune responses. Recently, they are also considered as delivery vehicle for therapeutic proteins due to their characteristics of stability in body fluids and ability for target uptake. Also, they show less immune reactivity because the isolated exosome harboring therapeutic proteins can be from the same host. White-spotted flower chafer, Protaetia brevitarsis is one of the major insect commercially reared in Korea. There are bacterial and fungal pathogens causing diseases in the beetle, and these diseases incur economic loss to the larva-rearing farms. Due to their endosomal cargoes, exosomes are good candidates in use of disease diagnosis. In this study, we isolated insect exosome from the hemolymph of P. brevitarsis, and verified it by analysis of the exosome-specific surface proteins and RNA.

• Journal of Microbiology and Biotechnology
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• v.12 no.4
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• pp.674-678
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• 2002

Yersinia enterocolitica causes various diseases in humans, including enteritis. The onset of such diseases is closely related with the expression of important virulence factors, particularly outer membrane proteins (OMPs). The expression of OMPs depends on several factors, including temperature, and origin, biotype and serotype of the bacteria. Recently, concerns over food safety have increased along with the demand for the development of sensitive, rapid, and pathogen-specific detection methods. To develop a suitable detection method for Y. enterocolitica isolated from Korean moutainspring water and pig feces, the OMP expression patterns were analyzed phenotypically and immunologically using 12 representative strains from 51 Y. enterocolitica Korean isolates. A 38-kDa OMP was commonly observed in all strains. However, additional OMPs were also observed in different biotypes and serotypes as well as bacterial origins, by incubating Y. enterocolitica at a low temperature. The specificity of the 38-kDa OMP was confirmed by a Western blot analysis with antisera against Y. enterocolitica and Brucella abortus. The results, therefore, indicate that the 38-kDa OMP could be used as a marker for detecting Y. enterocolitica in the environment or for seromonitoring.