• Proceedings of the Microbiological Society of Korea Conference
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• 2002.10a
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• pp.94-99
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• 2002

The oceans cover about $71\%$ of the Earth's crust and contain nearly 300,000 described species. Free-living bacteria in the sea and symbiotic bacteria of marine invertebrates are proving to be valuable sources of useful bioactive compounds. Marine sponges, in particular, which contain diverse communities of bacteria, produce many classes of compounds that are unique to the marine environment. Uncultured microorganisms are commonly believed to represent $99.9\%$ of the whole microbial community. They have been investigated for the possibility of isolating and over-expressing genes in viable microorganisms. Strict symbiotic species that have been adapted to the host are candidate unculturable species. With the enormous potential for discovery, development, and market value of marine derived compounds, supply of the products is a major limiting factor for further development.

• The Plant Pathology Journal
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• v.20 no.1
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• pp.18-21
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• 2004

The root hair provides a major entering spot for the symbiotic legume rhizobia. It is obvious that dynamic cell wall modification occurs in the plant root hair during the early microbe invasion. Expansins are nondestructive cell wall-modifying proteins that are involved in cell growth and differentiation. Among about 40 expansin genes in Arabidopsis, two expansin genes are expressed specifically in the root hair cell. Orthologous genes of this Arabidopsis root hair expansins have been found in other Brassica members, rice, and Medicago truncatula (a legume). In this review, I discuss the probable function of expansins during the early symbiotic process between the root hair and microbes and the regulation of root hair expansin genes in a comparative approach.

• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.59.4-60
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• 2016

One important aspect of the late stage stellar evolution is the mass loss processes, where a significant amount of stellar material will be returned to the interstellar space to be used for stars of the next generation. Raman scattered O VI and He II by atomic hydrogen in symbiotic stars and young planetary nebulae are found to be excellent tools to investigate the mass loss processes and estimate the mass loss rate. These features appear near hydrogen Balmer emission lines due to the huge cross section in the vicinity of Lyman resonance transitions. With the capability of high spectral resolution and broad spectral coverage, BOES is an ideal instrument to perform Raman spectroscopy of these objects. In this talk, a cursory overview of our research activities on Raman spectroscopy of symbiotics and PNe using the BOES is presented.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.1
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• pp.83.2-83.2
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• 2014

We present the two high resolution spectra of the symbiotic star V1016 Cygni obtained with the Bohyunsan Optical Echelle Spectrograph in 2003 and 2005, from which we note the existence of the broad emission feature at 4881 ${\AA}$. We propose that this broad feature is formed from Raman scattering of Ne $VII{\lambda}973$ by atomic hydrogen. Thus far, the detection of Raman scattered lines by atomic hydrogen is limited to O $VI{\lambda\lambda}1032$, 1038 and He $II{\lambda\lambda}940$, 972 and 1025. We perform Monte Carlo simulations to fit the Raman scattered Ne $VII{\lambda}4881$ to investigate the basic spectroscopic properties concerning Ne $VII{\lambda}973$.

• The Korean Journal of Zoology
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• v.22 no.2
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• pp.67-81
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• 1979

Eelctron microscopic cytochemical methods reveal that acid phosphatase activity appears exclusively in vacuoles surrounding established symbiotes. However, copius amounts of acid phosphatase reaction product are visible between and around some of the degenerating symbiotes in the amebae after treatment of chloramphenicol. It is thought that bacteriostasis by chloramphenicol has served to lost the symbiotic interference to intracellular digestion by the ameba and possibly phodphatase enxymes have been implicated in phagocytosis and intracellular digestion of the symbiotic bacteria.

• Bulletin of the Korean Chemical Society
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• v.24 no.5
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• pp.623-626
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• 2003

Nematophin and its analog incorporating tryptamine unit have been isolated and characterized from strain XRPC of a symbiotic bacterium Xenorhabdus nematophilus, which was newly isolated from Korean entomopathogenic nematodes. The stereoselective synthesis of these compounds was accomplished, and the relative configurations were determined. Nematophin exhibited potent antibacterial activities over several strains of methicillin-resistant S. aureus (MRSA) comparable to those of vancomycin.

• Acta Via Serica
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• v.5 no.1
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• pp.187-198
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• 2020

This paper is devoted to the examination of the identity of the Sogdian descendants and their historical role in the second millennium CE. More specifically, it discusses the Sogdian connection to the later Iranic-speaking peoples of Central Asia, namely, the Sarts and the Tajiks. It then discusses the symbiotic relationship between the Sogdian descendants and the Mongols and the Mongol descendants (Chaghatays and Uzbeks) in Central Asia. In sum, this paper argues that the Sogdians did not perish after the Arab conquest of Central Asia in the eighth century CE. They survived under new exonyms Sart and Tajik. Like the Sogdians in pre-Islamic Central Asia, the Tajiks or Sarts played important historical roles in the Mongol and post-Mongol states of Central Asia, maintaining a symbiotic relationship with the nomad elites.

• Korean Journal of Ecology and Environment
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• v.53 no.4
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• pp.336-343
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• 2020

Large-scale cultivation of Microcystis aeruginosa in different light conditions was conducted for verifying the cell growth in a greenhouse system. Environmental and chemical parameters of the large-scale culture medium were measured for analyzing the interaction between M. aeruginosa and its symbiotic bacteria. During cultivation, a difference in cell growth pattern was observed between control (natural light) and light-limited groups (reduction of blue, green, and blue/green light, respectively). Comparing the control group, the light reduced groups showed slow and delayed cell growth through the cultivation period. Also, there is differences in the consuming pattern of total nitrogen and total phosphorus which indicated that the possibility of interaction between M. aeruginosa and symbiotic bacteria.

• Mycobiology
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• v.51 no.5
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• pp.281-287
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• 2023

The symbiotic association between fungus-gardening termites Macrotermes and its fungal symbiont has a moderate degree of specificity-although the symbiotic fungi (Termitomyces) form a monophyletic clade, there is not a one-to-one association between termite species and their fungus-garden associates. Here, we aim to determine the origin and phylogenetic relationships of Termitomyces in Oman. We used sequences of the internal transcribed spacer region (ITS) and the nuclear large subunit ribosomal RNA (LSU rRNA, 25S) gene and analyzed these with sequences of Termitomyces from other geographic areas. We find no evidence for more than a single colonization of Oman by Termitomyces. Unexpectedly, we find Termitomyces in Oman is most closely related to the symbiont of M. subhyalinus in West Africa rather than to those of geographically closer populations in East Africa.

• Transportation Technology and Policy
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• v.9 no.2
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• pp.19-29
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• 2012