• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.79.2-80
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• 2003

To better understand plant defense responses against pathogen attack, we identified the transcription factor-encoding genes in the hot pepper Capsicum annuum that show altered expression patterns during the hypersensitive response raised by challenge with bacterial pathogens. One of these genes, Ca1244, was characterized further. This gene encodes a plant-specific Type IIIA - zinc finger protein that contains two Cys$_2$His$_2$zinc fingers. Ca1244 expression is rapidly and specifically induced when pepper plants are challenged with bacterial pathogens to which they are resistant. In contrast, challenge with a pathogen to which the plants are susceptible only generates weak Ca1244 expression. Ca1244 expression is also strongly induced in pepper leaves by the exogenous application of ethephon, an ethylene releasing compound. Whereas, salicylic acid and methyl jasmonate had moderate effects. Pepper protoplasts expressing a Ca1244-smGFP fusion protein showed Ca1244 localizes in the nucleus. Transgenic tobacco plants overexpressing Ca1244 driven by the CaMV 355 promoter show increased resistance to challenge with a tobacco-specific bacterial pathogen. These plants also showed constitutive upregulation of the expression of multiple defense-related genes. These observations provide the first evidence that an Type IIIA - zinc finger protein, Ca1244, plays a crucial role in the activation of the pathogen defense response in plants.

• Research in Plant Disease
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• v.19 no.4
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• pp.265-272
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• 2013

Totally sixty three bacteria were isolated from lower stems showing symptoms of bacterial wilt on pepper plants in 14 counties of 7 provinces, Korea. The isolates showed strong pathogenicity on red pepper (cv. Daewang) and tomato (cv. Seogwang) seedlings. All virulent bacteria were identified as Ralstonia solanacearum based on colony types, physiological and biochemical tests and polymerase chain reaction (PCR). All R. solanacearum isolates from peppers were race 1. The bacterial isolates consisted of biovar 3 (27%) and biovar 4 (73%). Based on polymorphic PCR bands generated by repetitive sequence (rep-PCR), the 63 R. solanacearum isolates were divided into 12 groups at 70% similarity level. These results will be used as basic materials for resistant breeding program and efficient control against bacterial wilt disease of pepper.

• Journal of Microbiology and Biotechnology
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• v.24 no.6
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• pp.803-811
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• 2014

Concerns over drug-resistant bacteria have stimulated interest in developing alternative methods to control bacterial infections. Endolysin, a phage-encoded enzyme that breaks down bacterial peptidoglycan at the terminal stage of the phage reproduction cycle, is reported to be effective for the control of bacterial pathogenic bacteria. Bioinformatic analysis of the SPN9CC bacteriophage genome revealed a gene that encodes an endolysin with a domain structure similar to those of the endolysins produced by the P1 and P22 coliphages. The SPN9CC endolysin was purified with a C-terminal oligo-histidine tag. The endolysin was relatively stable and active over a broad temperature range (from $24^{\circ}C$ to $65^{\circ}C$). It showed maximal activity at $50^{\circ}C$, and its optimum pH range was from pH 7.5 to 8.5. The SPN9CC endolysin showed antimicrobial activity against only gram-negative bacteria and functioned by cutting the glycosidic bond of peptidoglycan. Interestingly, the SPN9CC endolysin could lyse intact gram-negative bacteria in the absence of EDTA as an outer membrane permeabilizer. The exogenous lytic activity of the SPN9CC endolysin makes it a potential therapeutic agent against gram-negative bacteria.

• Journal of Species Research
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• v.6 no.2
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• pp.91-100
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• 2017

Five bacterial strains, ES10-3-3-1, KKM10-2-2-1, Ant11, JM10-4-1-3, and KMS4-11 assigned to the genus Deinococcus were isolated from soil samples collected from Namyangju-si in Gyeonggi-do, Gangnam-gu and Dongdaemun-gu in Seoul, Korea. In addition, four bacterial strains, KKM10-2-7-2, JM10-2-5, JM10-2-6-2, and KKM10-2-3 assigned to the genus Hymenobacter were isolated from soil samples collected from Gangnam-gu and Dongdaemun-gu in Seoul, in South Korea. The five Deinococcus species were Gram-stain positive, pink-pigmented, and short-rod or coccus shaped. The four Hymenobacter species were Gram-stain negative, red-pigmented, and short-rod shaped. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strains ES10-3-3-1, KKM10-2-2-1, Ant11, JM10-4-1-3, and KMS4-11 were most closely related to Deinococcus citri $NCCP-154^T$ (with 99.8% similarity), Deinococcus grandis DSM $12784^T$ (99.0%), Deinococcus marmoris DSM $12784^T$ (98.8%), Deinococcus claudionis $PO-04-19-125^T$ (98.7%), and Deinococcus radioresistens $8A^T$ (99.8%), respectively. KKM10-2-7-2, JM10-2-5, JM10-2-6-2, and KKM10-2-3 were most closely related to Hymenobacter algoricola $VUG-A23a^T$ (99.1% similarity), Hymenobacter elongatus $VUG-A112^T$ (99.1% similarity), Hymenobacter gelipurpurascens $Txg1^T$ (99.1% similarity), and Hymenobacter psychrotolerans $Tibet-IIU11^T$ (99.3% similarity), respectively. These nine species have never been reported in Korea; thus, five Deinococcus species are reported in the family Deinococcaceae, order Deinococcales, class Deinococci, phylum Deinococcus-Thermus and four Hymenobacter species are reported in the family Cytophagaceae, order Cytophagales, class Cytophagia, phylum Bacteroidetes.

• The Plant Pathology Journal
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• v.32 no.1
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• pp.25-32
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• 2016

Potato is one of the most important crops worldwide. Its commercial cultivars are highly susceptible to many fungal and bacterial diseases. Among these, bacterial wilt caused by Ralstonia solanacearum causes significant yield loss. In the present study, integrated proteomics and genomics approaches were used in order to identify bacterial wilt resistant genes from Rs resistance potato cultivar CT-206-10. 2-DE and MALDI-TOF/TOF-MS analysis identified eight differentially abundant proteins including glycine-rich RNA binding protein (GRP), tomato stress induced-1 (TSI-1) protein, pathogenesis-related (STH-2) protein and pentatricopeptide repeat containing (PPR) protein in response to Rs infection. Further, semi-quantitative RT-PCR identified up-regulation in transcript levels of all these genes upon Rs infection. Taken together, our results showed the involvement of the identified proteins in the Rs stress tolerance in potato. In the future, it would be interesting to raise the transgenic plants to further validate their involvement in resistance against Rs in potato.

• Korean Journal of Microbiology
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• v.41 no.1
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• pp.47-52
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• 2005

This study was carried out to identify bacterial strains adhered to human scalp hair and to investigate the antibiotic susceptibility of them. A total of 39 isolates were obtained from patients in intensive care units and healthy persons. The most common species isolated was Staphylococcus epidermidis (19 isolates), followed by S. aureus (14 isolates), S. waneri (5 isolates), and S. pasteuri (1 isolate). The susceptibility of isolates to amikacin, ampicillin, bacitracin, carbenicillin, cefazolin, cefoperazone, chloramphenicol, erythromycin, gentamicin, methicillin, nalidixic acid, neomycin, oxacillin, penicillin, streptomycin, tetracycline and vancomycin was determined by the disk diffusion method. All of the antibiotic resistant isolates were obtained from patient scalp hair. To examine the effect of conventional shampoo and detergent SDS on removing of bacteria from hair, we treated hair with culture solution of S. aureus. The bacteria attached to hair were not removed even by repeated washing with detergents. These results suggested that hair could be a source of bacterial contamination in hospital.

• Journal of Microbiology and Biotechnology
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• v.20 no.5
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• pp.935-941
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• 2010

The emergence of antibiotic-resistant bacterial strains is one of the most critical problems of modern medicine. Bacteriophages have been suggested as an alternative therapeutic agent for such bacterial infections. In the present study, we examined the therapeutic potential of phage Kpn5 in the treatment of Klebsiella pneumoniae B5055-induced burn wound infection in a mouse model. An experimental model of contact burn wound infection was established in mice employing K. pneumoniae B5055 to assess the efficacy of phage Kpn5 in vivo. Survival and stability of phage Kpn5 were evaluated in mice and the maximum phage count in various organs was obtained at 6 h and persisted until 36 h. The Kpn5 phage was found to be effective in the treatment of Klebsiella-induced burn wound infection in mice when phage was administered immediately after bacterial challange. Even when treatment was delayed up to 18 h post infection, when all animals were moribund, approximately 26.66% of the mice could be rescued by a single injection of this phage preparation. The ability of this phage to protect bacteremic mice was demonstrated to be due to the functional capabilities of the phage and not due to a nonspecific immune effect. The levels of pro-inflammatory cytokines (IL-$1{\beta}$ and TNF-${\alpha}$) and anti-inflammatory cytokines (IL-10) were significantly lower in sera and lungs of phage-treated mice than phage untreated control mice. The results of the present study bring out the potential of bacteriophage therapy as an alternate preventive approach to treat K. pneumoniae B5055-induced burn wound infections. This approach not only helps in the clearance of bacteria from the host but also protects against the ensuing inflammatory damage due to the exaggerated response seen in any infectious process.

• Korean Journal of Plant Resources
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• v.18 no.1
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• pp.198-206
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• 2005

This study was carried out to identify bacterial strains adhered to domestic pet dog hair and to identify antibacterial extracts from natural compounds. A total of 76 strains were isolated from dog hair. The most common species isolated was Staphylococcus spp. (41 isolates), followed by Micrococcus spp. (21 isolates), Enterococcus spp. (8 isolates), Bacillus sup. (3 isolates), Exiguobacterium sup. (2 isolates), Shigella spp. (1 isolate) and Zoogloea spp. (1 isolate). These results suggested that dog hair could be a source of bacterial contamination to human. The susceptibility of isolates to antibiotics and antibacterial activities of the natural compounds were examined by disk diffusion method. Water and ethanol extract from Scutellaria baicalensis revealed high antibacterial activities against Staphylococcus, Micrococcus, Enterococcus and Shigella. Our results suggest that the extract of Scutellaria baicalensis can be used a antibacterial agent against the antibiotic-resistant microorganisms.

• Journal of Species Research
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• v.7 no.3
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• pp.222-230
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• 2018

Six bacterial strains 18JY42-3, 18SH, 18JY76-11, 17J11-11, 18JY14-14, and 18JY15-11 assigned to the phylum Proteobacteria, Firmicutes, and Actinobacteria were isolated from soil samples in Korea. The Cohnella species, strain 18JY42-3 was Gram-stain-positive, short rod-shaped and beige-colored. The Methylobacterium species, strains 18SH and 18JY76-11 were Gram-stain-negative, short rod-shaped and pink-colored. The Microterricola species, strain 17J11-11 was Gram-stain-positive, short rod-shaped and yellow-colored. The Paenarthrobacter species, strains 18JY14-14 and 18JY15-11 were Gram-stain-positive, short rod-shaped and white-colored. Phylogenetic analysis based on 16S rRNA gene sequence showed that strains 18JY42-3, 18SH, 18JY76-11, 17J11-11, 18JY14-14, and 18JY15-11 were most closely related Cohnella rhizosphaerae (MH497628; 98.8%), Methylobacterium goesingense (MH497632; 99.1%), Methylobacterium populi (MH497635; 99.9%), Microterricolagilva (MH504108; 98.4%), Paenarthrobacter nicotinovorans (MH497641; 100%), and Paenarthrobacter nitroguajacolicus (MH497646; 99.2%), respectively. All the six unrecorded strains showed resistance to UV radiation. This is the first report of these six species in Korea.

• Journal of the Korean Society of Tobacco Science
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• v.17 no.1
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• pp.27-32
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• 1995

A new flue-cured tobacco mutant line BU 8832-85 was developed at Taegu Experiment Station, Korea Ginseng and Tobacco Research Institute in 1994. KF 8832-85 was resulted from a cross of flue-cured cultivars NC 95$\times$NC 2326, and developed by a pedigree system of breeding ; initial selection was made by plant type and resistance to bacterial wilt(BW) disease(heudomonas solanaceamm) in the F2 generation under the natural field conditions infested with the pathogen. One white flowered plant was occurred by spontaneous mutation in a certain line among the F3 generatioin while the others were pink. Six plants from the seeds by selfing were selected at the field infested with the pathogen among 240 populations with white flowering in the F4, KF 8832-85 was selected based on yield and leaf quality trials among 6 lines in Fs generation. BCF 8832-85 was compared with its Parent for certain agronomic and chemical characteristics at Taegu Experiment Station in 1993 and 1994. The results showed that KF 8832-85 have white flower, the stalk height was approximately that of NC 2326 but averaged about loom taller than NC 95. It produced ground suckers as much as NC 95, and did not breakdown leaf at the same as WC 2326. KF 8832-85 have high resistance to bacterial wilt disease. Yield of KF 8832-85 was 10 and 18% higher then that of NC 2326 and WC 95, respectively. Price per Kg was equal to that of NC 2326. The contents of nicotine and reducing sugar did not differ significantly from NC 95, while total nitrogen was significantly lower than NC 95. Therefore, the new mutant line is genetically stable for agronomic and chemical characteristics and provides a source of bacterial wilt disease resistance for use in breeding resistant flue-cured cultivars. Key words : Mutant line, White flower, Spontaneous mutation.