• Microbiology and Biotechnology Letters
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• v.13 no.3
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• pp.251-255
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• 1985

Nitrogen-fixing bacteria were isolated from the rice rhizosphere of various paddy fields in our country. The screening of 235 isolates for nitrogen-fixing ability resulted in the isolation of Enterobacter agglomerans NFB264 and three Klebsiella pneumoniae NFB 3, NFB 320. Plasmids of various molecular weight from 1.7 to more than 84 Mal. were detected by agarose gel electrophoresis in three out of four isolates. But, these plasmids had not any nitrogen-fixing genes. Hybridization experiments using Klebsiella pneumoniae M5al nitrogen-fixing genes, nif Q-K and nif DH, as probes revealed the presence of homologous sequences in the chromosomal DNA of all isolates. However the restriction patterns of nif genes of the isolates by various restriction endonucleases were different to those of Klebsiella pneumoniae M5al.

• Korean Journal of Microbiology
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• v.22 no.4
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• pp.265-269
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• 1984

For the utilization as donor cells of conjugation, DAP-Auxotrophs were isolated from C. coli cells, carrying plasmid $p^{RD1}$ with(a) drug resistance makers from Pseudononas $(Km^r, \;Carb^r, \;Tc^r)$ and (b) the nif-gene group from Klebsiela. E. coli $p^{RD1}$ cells were treated with nitrosoguanidine for the mutagenesis and cephalexin for the isolation of DAP-Auxotrophs. The nature of auxotrophs was verified by suitable biochemical test and checking with 6-cyanopurine as a color indicator for the presence of nif-gene.

• Journal of the Korean Magnetic Resonance Society
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• v.17 no.2
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• pp.105-110
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• 2013

HP1492 is a NifU-like protein of Helicobacter pylori (H. pylori) and plays a role as a scaffold which transfer Fe-S cluster to Fe-S proteins like Ferredoxin. To understand how to bind to iron ion or iron-sulfur cluster, HP1492 was expressed and purified in Escherichia coli (E. coli). From the NMR measurement, we could carry out the sequence specific backbone resonance assignment of HP1492. Approximately 91% of all resonances could be assigned unambiguously. By analyzing results of CSI and TALOS from NMR data, we could predict the secondary structure of HP1492, which consists of three ${\alpha}$-helices and three ${\beta}$-sheets. This study is an essential step towards the structural characterization of HP1492.

• Proceedings of the Microbiological Society of Korea Conference
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• 1991.04a
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• pp.213-224
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• 1991

• Proceedings of the Zoological Society Korea Conference
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• 2001.10a
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• pp.220.3-221
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• 2001

No Abstract, See Full Text

• Proceedings of the Zoological Society Korea Conference
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• 1994.10a
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• pp.235.2-235
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• 1994

• Proceedings of the Zoological Society Korea Conference
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• 1997.10b
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• pp.271.1-271
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• 1997

No Abstract, See Full Text

• Proceedings of the Zoological Society Korea Conference
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• 1997.10b
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• pp.271.2-271
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• 1997

No Abstract, See Full Text

• Journal of Korean Clinical Health Science
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• v.7 no.1
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• pp.1232-1237
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• 2019

Purpose. In this study, two types of soft contact lenses with different materials were selected to compare the time of tear film destruction and high order aberrations before and after wearing. Methods. Thirty patients (60 eyes) in their 20s were included in this study. Two lenses with different materials, Group 4 (Etafilcon A) and Group 5 (Narafilcon A) were selected. Using aberration analyzer and keratometry, high-order aberration and tear film test (NIF-BUT, NIAvg-BUT) were performed before and after wearing. Results. When comparing the higher aberrations of the Etafilcon A and Narafilcon A lenses, the higher aberrations of the Narafilcon A lens were higher overall. For the initial tear film break-up time (NIF-BUT) after wearing, the Etafilcon A lens was reduced by 4.0 seconds and the Narafilcon A lens increased by 0.6 seconds. For the mean tear film break-up time (NIAvg-BUT) after wearing, the Etafilcon A lens decreased by 2.4 seconds and the Narafilcon A lens increased by 1.7 seconds. Conclusions. NIF-BUT and NIAvg-BUT of Narafilcon A lens were increased. The lens with relatively low water content and higher oxygen permeability than the lens with high water content has relatively less tear evaporation, which means that the time of destruction of the tear film is increased.

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.1
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• pp.60-66
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• 1990

Soybean [Glycin max (L.)] cv. Jangbaekkong was inoculated with 5 cultivated- and 5 uncultivated upland soils, in Yeongnam area, as soil inoculum and NifTAL peat inoculum as standard for soil inoculum potentials by Bradyrhizobium japonicum. 120 Bradyrhizobium japonicum isolates out of the soil populations were scored of three colony morphologies, designed "Dry", "Wet", and "Dry/Wet", and symbiotic effectiveness between "Dry" and "Wet" was compared. The results obtained were summarized as follows: 1. Indigenous populations of B. japonicum were above $10^4cells/g$. soil at the cultivated upland soils but were a few at the uncultivated upland soils except a colluvivum, orchard previously, in Yeongnam area. 2. Inoculum potentials of the cultivated upland soils were higher than the NifTAL inoculum and generally, nodule mass compensated nodule number for symbiotic effectiveness of soil populations. 3. Colony morphologies of soil populations showed the different proportions of "Dry" and "Wet" so that "Dry" types were dominant at the cultivated upland soils while "Wet" types at the uncultivated upland soils. 4. "Dry" colony morphology significantly exhibited higher symbiotic effectiveness than "Wet" types in nodule fresh weight, shoot dry weight, and shoot dry weight/nodule fresh weight. Therefore, as long as soil inoculum potentials, the growth of soybean at the cultivated upland soils could presumedly be affected by soil populations of Bradyrhizobium japonicum of "Dry" colony morphology.